Merge branch 'master' into fix-5227

algorithms-miscellaneous-3/pom.xml

@@ -37,7 +37,7 @@
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-lang3</artifactId>
-            <version>${commons.lang3.version}</version>
+            <version>${commons-lang3.version}</version>
         </dependency>
         <dependency>
             <groupId>pl.pragmatists</groupId>
@@ -63,10 +63,8 @@
     </dependencies>
 
     <properties>
-        <commons-collections4.version>4.3</commons-collections4.version>
         <guava.version>28.0-jre</guava.version>
         <retrofit.version>2.6.0</retrofit.version>
-        <commons.lang3.version>3.8.1</commons.lang3.version>
         <JUnitParams.version>1.1.0</JUnitParams.version>
     </properties>
 

apache-poi-2/.gitignore

@@ -0,0 +1,3 @@
+*.docx
+temp.xls
+temp.xlsx

apache-poi-2/README.md

@@ -0,0 +1,8 @@
+## Apache POI
+
+This module contains articles about Apache POI
+
+### Relevant Articles:
+
+- [Adding a Column to an Excel Sheet Using Apache POI](https://www.baeldung.com/java-excel-add-column)
+- More articles: [[<-- prev]](/apache-poi)

apache-poi-2/pom.xml

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>apache-poi</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>apache-poi</name>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.apache.poi</groupId>
+            <artifactId>poi-ooxml</artifactId>
+            <version>5.0.0</version>
+        </dependency>
+    </dependencies>
+
+</project>

apache-poi-2/src/main/java/com/baeldung/poi/excel/newcolumn/ExcelColumn.java

@@ -0,0 +1,16 @@
+package com.baeldung.poi.excel.newcolumn;
+import org.apache.poi.ss.usermodel.CellType;
+import org.apache.poi.ss.usermodel.Row;
+import org.apache.poi.ss.usermodel.Sheet;
+import org.apache.poi.ss.usermodel.Workbook;
+import org.apache.poi.xssf.usermodel.XSSFWorkbook;
+
+
+public class ExcelColumn {
+
+    public void addColumn(Sheet sheet, CellType cellType) {
+        for (Row currentRow : sheet) {
+            currentRow.createCell(currentRow.getLastCellNum(), cellType);
+        }
+    }
+}

apache-poi-2/src/test/java/com/baeldung/poi/excel/newcolumn/ExcelColumnUnitTest.java

@@ -0,0 +1,40 @@
+package com.baeldung.poi.excel.newcolumn;
+
+import org.apache.poi.ss.usermodel.CellType;
+import org.apache.poi.ss.usermodel.Row;
+import org.apache.poi.ss.usermodel.Sheet;
+import org.apache.poi.ss.usermodel.Workbook;
+import org.apache.poi.xssf.usermodel.XSSFWorkbook;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.net.URISyntaxException;
+import java.nio.file.Paths;
+
+import static org.junit.Assert.assertEquals;
+
+public class ExcelColumnUnitTest {
+    private static final String FILE_NAME = "newColumnTest.xlsx";
+    private String fileLocation;
+
+    @Before
+    public void setup() throws URISyntaxException {
+        fileLocation = Paths.get(ClassLoader.getSystemResource(FILE_NAME).toURI()).toString();
+    }
+
+    @Test
+    public void givenExistingRows_whenAddNewColumn_thenRowColumnNumberIncreased() throws IOException {
+        Workbook workbook = new XSSFWorkbook(fileLocation);
+        Sheet sheet = workbook.getSheetAt(0);
+        Row row = sheet.getRow(0);
+        assertEquals(5, row.getLastCellNum());
+
+        ExcelColumn excelColumn = new ExcelColumn();
+        excelColumn.addColumn(sheet, CellType.STRING);
+        assertEquals(6, row.getLastCellNum());
+
+        workbook.close();
+    }
+
+}

apache-poi/README.md

@@ -15,3 +15,4 @@ This module contains articles about Apache POI
 - [Multiline Text in Excel Cell Using Apache POI](https://www.baeldung.com/apache-poi-write-multiline-text)
 - [Set Background Color of a Cell with Apache POI](https://www.baeldung.com/apache-poi-background-color)
 - [Add Borders to Excel Cells With Apache POI](https://www.baeldung.com/apache-poi-add-borders)
+- More articles: [[next -->]](/apache-poi-2)

apache-poi/src/main/java/com/baeldung/poi/excel/ExcelUtility.java

@@ -0,0 +1,66 @@
+package com.baeldung.poi.excel;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+
+import org.apache.poi.ss.usermodel.Cell;
+import org.apache.poi.ss.usermodel.CellType;
+import org.apache.poi.ss.usermodel.DateUtil;
+import org.apache.poi.ss.usermodel.Row;
+import org.apache.poi.ss.usermodel.Sheet;
+import org.apache.poi.ss.usermodel.Workbook;
+import org.apache.poi.xssf.usermodel.XSSFWorkbook;
+
+public class ExcelUtility {
+	private static final String ENDLINE = System.getProperty("line.separator");
+
+	public static String readExcel(String filePath) throws IOException {
+		File file = new File(filePath);
+		FileInputStream inputStream = null;
+		StringBuilder toReturn = new StringBuilder();
+		try {
+			inputStream = new FileInputStream(file);
+			Workbook baeuldungWorkBook = new XSSFWorkbook(inputStream);
+			for (Sheet sheet : baeuldungWorkBook) {
+				toReturn.append("--------------------------------------------------------------------").append(ENDLINE);
+				toReturn.append("Worksheet :").append(sheet.getSheetName()).append(ENDLINE);
+				toReturn.append("--------------------------------------------------------------------").append(ENDLINE);
+				int firstRow = sheet.getFirstRowNum();
+				int lastRow = sheet.getLastRowNum();
+				for (int index = firstRow + 1; index <= lastRow; index++) {
+					Row row = sheet.getRow(index);
+					toReturn.append("|| ");
+					for (int cellIndex = row.getFirstCellNum(); cellIndex < row.getLastCellNum(); cellIndex++) {
+						Cell cell = row.getCell(cellIndex, Row.MissingCellPolicy.CREATE_NULL_AS_BLANK);
+						printCellValue(cell, toReturn);
+					}
+					toReturn.append(" ||").append(ENDLINE);
+				}
+			}
+			inputStream.close();
+
+		} catch (IOException e) {
+			throw e;
+		}
+		return toReturn.toString();
+	}
+
+	public static void printCellValue(Cell cell, StringBuilder toReturn) {
+		CellType cellType = cell.getCellType().equals(CellType.FORMULA) ? cell.getCachedFormulaResultType()
+				: cell.getCellType();
+		if (cellType.equals(CellType.STRING)) {
+			toReturn.append(cell.getStringCellValue()).append(" | ");
+		}
+		if (cellType.equals(CellType.NUMERIC)) {
+			if (DateUtil.isCellDateFormatted(cell)) {
+				toReturn.append(cell.getDateCellValue()).append(" | ");
+			} else {
+				toReturn.append(cell.getNumericCellValue()).append(" | ");
+			}
+		}
+		if (cellType.equals(CellType.BOOLEAN)) {
+			toReturn.append(cell.getBooleanCellValue()).append(" | ");
+		}
+	}
+}

apache-poi/src/test/java/com/baeldung/poi/excel/ExcelUtilityUnitTest.java

@@ -0,0 +1,54 @@
+package com.baeldung.poi.excel;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import java.io.IOException;
+import java.net.URISyntaxException;
+import java.nio.file.Paths;
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+
+import org.junit.Before;
+import org.junit.Test;
+
+public class ExcelUtilityUnitTest {
+	private static final String FILE_NAME = "baeldung.xlsx";
+	private String fileLocation;
+	private static final String ENDLINE = System.getProperty("line.separator");
+	private StringBuilder output;
+
+	@Before
+	public void setupUnitTest() throws IOException, URISyntaxException, ParseException {
+		output = new StringBuilder();
+		output.append("--------------------------------------------------------------------").append(ENDLINE);
+		output.append("Worksheet :Sheet1").append(ENDLINE);
+		output.append("--------------------------------------------------------------------").append(ENDLINE);
+		output.append("|| Name1 | Surname1 | 3.55696564113E11 | ").append(new SimpleDateFormat("dd/MM/yyyy").parse("4/11/2021").toString()).append(" | ‡ |  ||")
+				.append(ENDLINE);
+		output.append("|| Name2 | Surname2 | 5.646513512E9 | ").append(new SimpleDateFormat("dd/MM/yyyy").parse("4/12/2021").toString()).append(" | false |  ||")
+				.append(ENDLINE);
+		output.append("|| Name3 | Surname3 | 3.55696564113E11 | ").append(new SimpleDateFormat("dd/MM/yyyy").parse("4/11/2021").toString()).append(" | 7.17039641738E11 |  ||")
+				.append(ENDLINE);
+		output.append("--------------------------------------------------------------------").append(ENDLINE);
+		output.append("Worksheet :Sheet2").append(ENDLINE);
+		output.append("--------------------------------------------------------------------").append(ENDLINE);
+		output.append("|| Name4 | Surname4 | 3.55675623232E11 | 13/04/2021 |  ||").append(ENDLINE);
+
+		fileLocation = Paths.get(ClassLoader.getSystemResource(FILE_NAME).toURI()).toString();
+	}
+
+	@Test
+	public void givenStringPath_whenReadExcel_thenReturnStringValue() throws IOException {
+		assertEquals(output.toString(), ExcelUtility.readExcel(fileLocation));
+
+	}
+
+	@Test
+	public void givenStringPath_whenReadExcel_thenThrowException() {
+		assertThrows(IOException.class, () -> {
+			ExcelUtility.readExcel("baeldung");
+		});
+	}
+
+}

aws-lambda/lambda/pom.xml

@@ -10,9 +10,8 @@
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
+        <artifactId>aws-lambda</artifactId>
         <version>1.0.0-SNAPSHOT</version>
-        <relativePath>../../</relativePath>
     </parent>
 
     <dependencies>

aws-lambda/pom.xml

@@ -11,7 +11,6 @@
         <groupId>com.baeldung</groupId>
         <artifactId>parent-modules</artifactId>
         <version>1.0.0-SNAPSHOT</version>
-        <relativePath>../</relativePath>
     </parent>
 
     <modules>

cloud-foundry-uaa/cf-uaa-oauth2-client/pom.xml

@@ -10,9 +10,8 @@
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-boot-2</artifactId>
+        <artifactId>cloud-foundry-uaa</artifactId>
         <version>0.0.1-SNAPSHOT</version>
-        <relativePath>../../parent-boot-2</relativePath>
     </parent>
 
     <dependencies>

cloud-foundry-uaa/cf-uaa-oauth2-resource-server/pom.xml

@@ -10,9 +10,8 @@
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-boot-2</artifactId>
+        <artifactId>cloud-foundry-uaa</artifactId>
         <version>0.0.1-SNAPSHOT</version>
-        <relativePath>../../parent-boot-2</relativePath>
     </parent>
 
     <dependencies>

cloud-foundry-uaa/pom.xml

@@ -4,14 +4,14 @@
     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
     <artifactId>cloud-foundry-uaa</artifactId>
-    <version>0.0.1-SNAPSHOT</version>
     <name>cloud-foundry-uaa</name>
     <packaging>pom</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
+        <artifactId>parent-boot-2</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../parent-boot-2</relativePath>
     </parent>
 
     <modules>

core-java-modules/core-java-10/pom.xml

@@ -39,7 +39,6 @@
     <properties>
         <maven.compiler.source.version>10</maven.compiler.source.version>
         <maven.compiler.target.version>10</maven.compiler.target.version>
-        <commons-collections4.version>4.1</commons-collections4.version>
     </properties>
 
 </project>

core-java-modules/core-java-11-2/src/test/java/com/baeldung/version/VersionManualTest.java

@@ -5,7 +5,8 @@ import org.assertj.core.api.Assertions;
 import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 
-public class VersionUnitTest {
+// manual test as the runtime JDK version can be different depending on where the test is run
+public class VersionManualTest {
 
     @Test
     public void givenJava_whenUsingRuntime_thenGetVersion() {

core-java-modules/core-java-8/pom.xml

@@ -43,9 +43,4 @@
         </resources>
     </build>
 
-    <properties>
-        <!-- util -->
-        <commons-collections4.version>4.1</commons-collections4.version>
-    </properties>
-
 </project>

core-java-modules/core-java-9-jigsaw/src/test/java/com/baeldung/java9/modules/ModuleAPIUnitTest.java

@@ -16,6 +16,7 @@ import java.util.stream.Collectors;
 
 import org.junit.Before;
 import org.junit.Test;
+import org.junit.Ignore;
 
 public class ModuleAPIUnitTest {
 
@@ -110,6 +111,7 @@ public class ModuleAPIUnitTest {
     }
 
     @Test
+    @Ignore // fixing in http://team.baeldung.com/browse/JAVA-8679
     public void givenModules_whenAccessingModuleDescriptorProvides_thenProvidesAreReturned() {
         Set<Provides> javaBaseProvides = javaBaseModule.getDescriptor().provides();
         Set<Provides> javaSqlProvides = javaSqlModule.getDescriptor().provides();

core-java-modules/core-java-9/pom.xml

@@ -76,7 +76,6 @@
         <maven.compiler.source>1.9</maven.compiler.source>
         <maven.compiler.target>1.9</maven.compiler.target>
         <guava.version>25.1-jre</guava.version>
-        <commons-collections4.version>4.1</commons-collections4.version>
     </properties>
 
 </project>

core-java-modules/core-java-collections-2/pom.xml

@@ -44,7 +44,6 @@
 
     <properties>
         <eclipse.collections.version>7.1.0</eclipse.collections.version>
-        <commons-collections4.version>4.1</commons-collections4.version>
         <commons-exec.version>1.3</commons-exec.version>
     </properties>
 

core-java-modules/core-java-collections-4/src/main/java/com/baeldung/collections/mulipletypesinmap/DynamicTypeValue.java

@@ -0,0 +1,5 @@
+package com.baeldung.collections.mulipletypesinmap;
+
+public interface DynamicTypeValue {
+    String valueDescription();
+}

core-java-modules/core-java-collections-4/src/main/java/com/baeldung/collections/mulipletypesinmap/InstantTypeValue.java

@@ -0,0 +1,24 @@
+package com.baeldung.collections.mulipletypesinmap;
+
+import java.time.Instant;
+import java.time.ZoneId;
+import java.time.format.DateTimeFormatter;
+
+public class InstantTypeValue implements DynamicTypeValue {
+    private static DateTimeFormatter FORMATTER = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")
+        .withZone(ZoneId.systemDefault());
+    private Instant value;
+
+    public InstantTypeValue(Instant value) {
+        this.value = value;
+    }
+
+    @Override
+    public String valueDescription() {
+        if (value == null) {
+            return "The value is null.";
+        }
+        return String.format("The value is an instant: %s", FORMATTER.format(value));
+    }
+
+}

core-java-modules/core-java-collections-4/src/main/java/com/baeldung/collections/mulipletypesinmap/IntArrayTypeValue.java

@@ -0,0 +1,20 @@
+package com.baeldung.collections.mulipletypesinmap;
+
+import java.util.Arrays;
+
+public class IntArrayTypeValue implements DynamicTypeValue {
+    private int[] value;
+
+    public IntArrayTypeValue(int[] value) {
+        this.value = value;
+    }
+
+    @Override
+    public String valueDescription() {
+        if (value == null) {
+            return "The value is null.";
+        }
+        return String.format("The value is an array of %d integers: %s", value.length, Arrays.toString(value));
+    }
+
+}

core-java-modules/core-java-collections-4/src/main/java/com/baeldung/collections/mulipletypesinmap/IntegerTypeValue.java

@@ -0,0 +1,17 @@
+package com.baeldung.collections.mulipletypesinmap;
+
+public class IntegerTypeValue implements DynamicTypeValue {
+    private Integer value;
+
+    public IntegerTypeValue(Integer value) {
+        this.value = value;
+    }
+
+    @Override
+    public String valueDescription() {
+        if(value == null){
+            return "The value is null.";
+        }
+        return String.format("The value is a %s integer: %d", value > 0 ? "positive" : "negative", value);
+    }
+}

core-java-modules/core-java-collections-4/src/test/java/com/baeldung/multipletypesinmap/MultipleTypesInMapUnitTest.java

@@ -0,0 +1,75 @@
+package com.baeldung.multipletypesinmap;
+
+import com.baeldung.collections.mulipletypesinmap.DynamicTypeValue;
+import com.baeldung.collections.mulipletypesinmap.InstantTypeValue;
+import com.baeldung.collections.mulipletypesinmap.IntArrayTypeValue;
+import com.baeldung.collections.mulipletypesinmap.IntegerTypeValue;
+import org.junit.jupiter.api.Test;
+
+import java.time.Instant;
+import java.time.ZoneId;
+import java.time.format.DateTimeFormatter;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Map;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class MultipleTypesInMapUnitTest {
+    private static final DateTimeFormatter FORMATTER = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")
+        .withZone(ZoneId.systemDefault());
+
+    private static final Integer intValue = 777;
+    private static final int[] intArray = new int[]{2, 3, 5, 7, 11, 13};
+    private static final Instant instant = Instant.now();
+
+    private static final String KEY_INT = "E1 (Integer)";
+    private static final String KEY_INT_ARRAY = "E2 (IntArray)";
+    private static final String KEY_INSTANT = "E3 (Instant)";
+
+    @Test
+    void givenThreeTypes_whenUsingRawMap_thenPrintDescription() {
+        Map<String, Object> rawMap = new HashMap<>();
+        rawMap.put(KEY_INT, intValue);
+        rawMap.put(KEY_INT_ARRAY, intArray);
+        rawMap.put(KEY_INSTANT, instant);
+
+        rawMap.forEach((k, v) -> {
+            if (v instanceof Integer) {
+                Integer theV = (Integer) v;
+                String desc = String.format("The value is a %s integer: %d", theV > 0 ? "positive" : "negative", theV);
+                System.out.println(k + " -> " + desc);
+                assertThat(k).isEqualTo(KEY_INT);
+                assertThat(desc).isEqualTo("The value is a positive integer: 777");
+            } else if (v instanceof int[]) {
+                int[] theV = (int[]) v;
+                String desc = String.format("The value is an array of %d integers: %s", theV.length, Arrays.toString(theV));
+                System.out.println(k + " -> " + desc);
+                assertThat(k).isEqualTo(KEY_INT_ARRAY);
+                assertThat(desc).isEqualTo("The value is an array of 6 integers: [2, 3, 5, 7, 11, 13]");
+            } else if (v instanceof Instant) {
+                Instant theV = (Instant) v;
+                String desc = String.format("The value is an instant: %s", FORMATTER.format(theV));
+                System.out.println(k + " -> " + desc);
+                assertThat(k).isEqualTo(KEY_INSTANT);
+                assertThat(desc).matches("^The value is an instant: \\d{4}-\\d{2}-\\d{2} \\d{2}:\\d{2}:\\d{2}");
+            } else {
+                throw new IllegalStateException("Unknown Type found.");
+            }
+        });
+    }
+
+    @Test
+    void givenThreeTypes_whenUsingAnInterface_thenPrintDescription() {
+        Map<String, DynamicTypeValue> theMap = new HashMap<>();
+        theMap.put(KEY_INT, new IntegerTypeValue(intValue));
+        theMap.put(KEY_INT_ARRAY, new IntArrayTypeValue(intArray));
+        theMap.put(KEY_INSTANT, new InstantTypeValue(instant));
+
+        theMap.forEach((k, v) -> System.out.println(k + " -> " + v.valueDescription()));
+
+        assertThat(theMap.get(KEY_INT).valueDescription()).isEqualTo("The value is a positive integer: 777");
+        assertThat(theMap.get(KEY_INT_ARRAY).valueDescription()).isEqualTo("The value is an array of 6 integers: [2, 3, 5, 7, 11, 13]");
+        assertThat(theMap.get(KEY_INSTANT).valueDescription()).matches("^The value is an instant: \\d{4}-\\d{2}-\\d{2} \\d{2}:\\d{2}:\\d{2}");
+    }
+}

core-java-modules/core-java-collections-array-list/pom.xml

@@ -22,8 +22,4 @@
         </dependency>
     </dependencies>
 
-    <properties>
-        <commons-collections4.version>4.1</commons-collections4.version>
-    </properties>
-
 </project>

core-java-modules/core-java-collections-list-2/pom.xml

@@ -28,8 +28,4 @@
         </dependency>
     </dependencies>
 
-    <properties>
-        <commons-collections4.version>4.1</commons-collections4.version>
-    </properties>
-
 </project>

core-java-modules/core-java-collections-list-3/pom.xml

@@ -54,7 +54,6 @@
     </dependencies>
 
     <properties>
-        <commons-collections4.version>4.1</commons-collections4.version>
         <trove4j.version>3.0.2</trove4j.version>
         <fastutil.version>8.1.0</fastutil.version>
         <colt.version>1.2.0</colt.version>

core-java-modules/core-java-collections-list/pom.xml

@@ -27,8 +27,4 @@
         </dependency>
     </dependencies>
 
-    <properties>
-        <commons-collections4.version>4.1</commons-collections4.version>
-    </properties>
-
 </project>

core-java-modules/core-java-collections-maps-2/pom.xml

@@ -55,7 +55,6 @@
 
     <properties>
         <streamex.version>0.6.5</streamex.version>
-        <commons-collections4.version>4.1</commons-collections4.version>
         <avaitility.version>1.7.0</avaitility.version>
         <eclipse-collections.version>8.2.0</eclipse-collections.version>
         <hppc.version>0.7.2</hppc.version>

core-java-modules/core-java-collections-maps-4/pom.xml

@@ -28,12 +28,6 @@
 			<version>${junit.version}</version>
 			<scope>test</scope>
 		</dependency>
-		<dependency>
-			<groupId>org.hamcrest</groupId>
-			<artifactId>hamcrest-all</artifactId>
-			<version>${hamcrest-all.version}</version>
-			<scope>test</scope>
-		</dependency>
 	</dependencies>
 
 	<build>

core-java-modules/core-java-collections-maps/pom.xml

@@ -22,8 +22,4 @@
         </dependency>
     </dependencies>
 
-    <properties>
-        <commons-collections4.version>4.1</commons-collections4.version>
-    </properties>
-
 </project>

core-java-modules/core-java-collections-set/pom.xml

@@ -49,7 +49,6 @@
     <properties>
         <maven.compiler.source>11</maven.compiler.source>
         <maven.compiler.target>11</maven.compiler.target>
-        <commons-collections4.version>4.3</commons-collections4.version>
         <gson.version>2.8.5</gson.version>
     </properties>
 

core-java-modules/core-java-concurrency-advanced/pom.xml

@@ -56,7 +56,6 @@
     <properties>
         <guava.version>21.0</guava.version>
         <commons-math3.version>3.6.1</commons-math3.version>
-        <commons-collections4.version>4.1</commons-collections4.version>
         <collections-generic.version>4.01</collections-generic.version>
         <avaitility.version>1.7.0</avaitility.version>
     </properties>

core-java-modules/core-java-exceptions-3/src/test/java/com/baeldung/exceptions/illegalmonitorstate/IllegalMonitorStateExceptionUnitTest.java

@@ -1,11 +1,12 @@
 package com.baeldung.exceptions.illegalmonitorstate;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
 import org.junit.jupiter.api.Test;
 
-import java.time.Duration;
-
-import static org.junit.jupiter.api.Assertions.*;
-
 public class IllegalMonitorStateExceptionUnitTest {
 
     @Test
@@ -20,11 +21,11 @@ public class IllegalMonitorStateExceptionUnitTest {
         Thread senderThread = new Thread(sender, "sender-thread");
         senderThread.start();
 
-        senderThread.join(1000);
+        // we need to wait for the sender and receiver threads to finish
-        receiverThread.join(1000);
+        senderThread.join(10_000);
+        receiverThread.join(10_000);
 
-        // we need to wait for enough time so that sender has had a chance to send the data
+        assertEquals("test", receiver.getMessage());
-        assertTimeout(Duration.ofSeconds(10), () -> assertEquals("test", receiver.getMessage()));
         assertFalse(sender.hasIllegalMonitorStateExceptionOccurred());
         assertFalse(receiver.hasIllegalMonitorStateExceptionOccurred());
     }

core-java-modules/core-java-io-conversions/src/test/java/com/baeldung/readertox/JavaReaderToXUnitTest.java

@@ -1,7 +1,7 @@
 package com.baeldung.readertox;
 
 import static org.hamcrest.CoreMatchers.equalTo;
-import static org.junit.Assert.assertThat;
+import static org.hamcrest.MatcherAssert.assertThat;
 
 import java.io.ByteArrayInputStream;
 import java.io.File;
@@ -17,6 +17,7 @@ import java.nio.charset.StandardCharsets;
 import org.apache.commons.io.FileUtils;
 import org.apache.commons.io.IOUtils;
 import org.apache.commons.io.input.CharSequenceReader;
+import org.apache.commons.io.input.ReaderInputStream;
 import org.junit.Test;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -181,7 +182,7 @@ public class JavaReaderToXUnitTest {
     }
 
     @Test
-    public void givenUsingCommonsIO_whenConvertingReaderIntoInputStream() throws IOException {
+    public void givenUsingCommonsIOUtils_whenConvertingReaderIntoInputStream() throws IOException {
         final Reader initialReader = new StringReader("With Commons IO");
 
         final InputStream targetStream = IOUtils.toInputStream(IOUtils.toString(initialReader));
@@ -191,7 +192,7 @@ public class JavaReaderToXUnitTest {
     }
 
     @Test
-    public void givenUsingCommonsIO_whenConvertingReaderIntoInputStream_thenCorrect() throws IOException {
+    public void givenUsingCommonsIOUtils_whenConvertingReaderIntoInputStream_thenCorrect() throws IOException {
         String initialString = "With Commons IO";
         final Reader initialReader = new StringReader(initialString);
 
@@ -204,6 +205,30 @@ public class JavaReaderToXUnitTest {
         targetStream.close();
     }
 
+    @Test
+    public void givenUsingCommonsIOReaderInputStream_whenConvertingReaderIntoInputStream() throws IOException {
+        final Reader initialReader = new StringReader("With Commons IO");
+
+        final InputStream targetStream = new ReaderInputStream(initialReader);
+
+        initialReader.close();
+        targetStream.close();
+    }
+
+    @Test
+    public void givenUsingCommonsIOReaderInputStream_whenConvertingReaderIntoInputStream_thenCorrect() throws IOException {
+        String initialString = "With Commons IO";
+        final Reader initialReader = new StringReader(initialString);
+
+        final InputStream targetStream = new ReaderInputStream(initialReader);
+
+        final String finalString = IOUtils.toString(targetStream);
+        assertThat(finalString, equalTo(initialString));
+
+        initialReader.close();
+        targetStream.close();
+    }
+
     // tests - Reader to InputStream with encoding
 
     @Test
@@ -233,7 +258,7 @@ public class JavaReaderToXUnitTest {
     }
 
     @Test
-    public void givenUsingCommonsIO_whenConvertingReaderIntoInputStreamWithEncoding() throws IOException {
+    public void givenUsingCommonsIOUtils_whenConvertingReaderIntoInputStreamWithEncoding() throws IOException {
         final Reader initialReader = new StringReader("With Commons IO");
 
         final InputStream targetStream = IOUtils.toInputStream(IOUtils.toString(initialReader), Charsets.UTF_8);
@@ -243,7 +268,7 @@ public class JavaReaderToXUnitTest {
     }
 
     @Test
-    public void givenUsingCommonsIO_whenConvertingReaderIntoInputStreamWithEncoding_thenCorrect() throws IOException {
+    public void givenUsingCommonsIOUtils_whenConvertingReaderIntoInputStreamWithEncoding_thenCorrect() throws IOException {
         String initialString = "With Commons IO";
         final Reader initialReader = new StringReader(initialString);
         final InputStream targetStream = IOUtils.toInputStream(IOUtils.toString(initialReader), Charsets.UTF_8);
@@ -255,4 +280,27 @@ public class JavaReaderToXUnitTest {
         targetStream.close();
     }
 
+    @Test
+    public void givenUsingCommonsIOReaderInputStream_whenConvertingReaderIntoInputStreamWithEncoding() throws IOException {
+        final Reader initialReader = new StringReader("With Commons IO");
+
+        final InputStream targetStream = new ReaderInputStream(initialReader, Charsets.UTF_8);
+
+        initialReader.close();
+        targetStream.close();
+    }
+
+    @Test
+    public void givenUsingCommonsIOReaderInputStream_whenConvertingReaderIntoInputStreamWithEncoding_thenCorrect() throws IOException {
+        String initialString = "With Commons IO";
+        final Reader initialReader = new StringReader(initialString);
+
+        final InputStream targetStream = new ReaderInputStream(initialReader, Charsets.UTF_8);
+
+        String finalString = IOUtils.toString(targetStream, Charsets.UTF_8);
+        assertThat(finalString, equalTo(initialString));
+
+        initialReader.close();
+        targetStream.close();
+    }
 }

core-java-modules/core-java-lang-oop-modifiers/pom.xml

@@ -22,4 +22,7 @@
         </dependency>
     </dependencies>
 
+    <properties>
+        <h2.version>1.4.197</h2.version> <!-- needs to be specified as it fails with parent's 1.4.200 -->
+    </properties>
 </project>

core-java-modules/core-java-networking-3/README.md

@@ -9,4 +9,5 @@ This module contains articles about networking in Java
 - [Connection Timeout vs. Read Timeout for Java Sockets](https://www.baeldung.com/java-socket-connection-read-timeout)
 - [Find Whether an IP Address Is in the Specified Range or Not in Java](https://www.baeldung.com/java-check-ip-address-range)
 - [Find the IP Address of a Client Connected to a Server](https://www.baeldung.com/java-client-get-ip-address)
+- [Unix Domain Socket in Java 16](https://www.baeldung.com/java-unix-domain-socket)
 - [[<-- Prev]](/core-java-modules/core-java-networking-2)

core-java-modules/core-java-networking-3/pom.xml

@@ -64,6 +64,16 @@
                 </plugin>
             </plugins>
         </pluginManagement>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>16</source>
+                    <target>16</target>
+                </configuration>
+            </plugin>
+        </plugins>
     </build>
 
     <properties>

core-java-modules/core-java-networking-3/src/main/java/com/baeldung/socket/UnixDomainSocketClient.java

@@ -0,0 +1,49 @@
+package com.baeldung.socket;
+
+import java.io.IOException;
+import java.net.StandardProtocolFamily;
+import java.net.UnixDomainSocketAddress;
+import java.nio.ByteBuffer;
+import java.nio.channels.SocketChannel;
+import java.nio.file.Path;
+
+class UnixDomainSocketClient {
+
+    public static void main(String[] args) throws Exception {
+        new UnixDomainSocketClient().runClient();
+    }
+
+    void runClient() throws IOException {
+        Path socketPath = Path.of(System.getProperty("user.home"))
+          .resolve("baeldung.socket");
+        UnixDomainSocketAddress socketAddress = getAddress(socketPath);
+
+        SocketChannel channel = openSocketChannel(socketAddress);
+
+        String message = "Hello from Baeldung Unix domain socket article";
+        writeMessage(channel, message);
+    }
+
+    UnixDomainSocketAddress getAddress(Path socketPath) {
+        return UnixDomainSocketAddress.of(socketPath);
+    }
+
+    SocketChannel openSocketChannel(UnixDomainSocketAddress socketAddress) throws IOException {
+        SocketChannel channel = SocketChannel
+          .open(StandardProtocolFamily.UNIX);
+        channel.connect(socketAddress);
+        return channel;
+    }
+
+    void writeMessage(SocketChannel socketChannel, String message) throws IOException {
+        ByteBuffer buffer = ByteBuffer.allocate(1024);
+        buffer.clear();
+        buffer.put(message.getBytes());
+        buffer.flip();
+
+        while (buffer.hasRemaining()) {
+            socketChannel.write(buffer);
+        }
+    }
+
+}

core-java-modules/core-java-networking-3/src/main/java/com/baeldung/socket/UnixDomainSocketServer.java

@@ -0,0 +1,57 @@
+package com.baeldung.socket;
+
+import java.io.IOException;
+import java.net.StandardProtocolFamily;
+import java.net.UnixDomainSocketAddress;
+import java.nio.ByteBuffer;
+import java.nio.channels.ServerSocketChannel;
+import java.nio.channels.SocketChannel;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Optional;
+
+class UnixDomainSocketServer {
+
+    public static void main(String[] args) throws IOException, InterruptedException {
+        new UnixDomainSocketServer().runServer();
+    }
+
+    void runServer() throws IOException, InterruptedException {
+        Path socketPath = Path.of(System.getProperty("user.home"))
+          .resolve("baeldung.socket");
+        Files.deleteIfExists(socketPath);
+        UnixDomainSocketAddress socketAddress = getAddress(socketPath);
+
+        ServerSocketChannel serverChannel = createServerSocketChannel(socketAddress);
+
+        SocketChannel channel = serverChannel.accept();
+
+        while (true) {
+            readSocketMessage(channel)
+              .ifPresent(message -> System.out.printf("[Client message] %s%n", message));
+            Thread.sleep(100);
+        }
+    }
+
+    UnixDomainSocketAddress getAddress(Path socketPath) {
+        return UnixDomainSocketAddress.of(socketPath);
+    }
+
+    ServerSocketChannel createServerSocketChannel(UnixDomainSocketAddress socketAddress) throws IOException {
+        ServerSocketChannel serverChannel = ServerSocketChannel.open(StandardProtocolFamily.UNIX);
+        serverChannel.bind(socketAddress);
+        return serverChannel;
+    }
+
+    Optional<String> readSocketMessage(SocketChannel channel) throws IOException {
+        ByteBuffer buffer = ByteBuffer.allocate(1024);
+        int bytesRead = channel.read(buffer);
+        if (bytesRead < 0) return Optional.empty();
+        byte[] bytes = new byte[bytesRead];
+        buffer.flip();
+        buffer.get(bytes);
+        String message = new String(bytes);
+        return Optional.of(message);
+    }
+
+}

core-java-modules/core-java-networking-3/src/test/java/com/baeldung/socket/FindFreePortManualTest.java

@@ -14,7 +14,8 @@ import java.net.ServerSocket;
 import static org.assertj.core.api.Assertions.*;
 import static org.assertj.core.api.Assertions.assertThat;
 
-public class FindFreePortUnitTest {
+// fixing in JAVA-8748
+public class FindFreePortManualTest {
 
     private static int FREE_PORT_NUMBER;
     private static int[] FREE_PORT_RANGE;

core-java-modules/core-java-networking-3/src/test/java/com/baeldung/socket/UnixDomainSocketClientUnitTest.java

@@ -0,0 +1,82 @@
+package com.baeldung.socket;
+
+import org.junit.Test;
+import org.mockito.Mockito;
+import org.mockito.stubbing.Answer;
+
+import java.io.File;
+import java.io.IOException;
+import java.net.StandardProtocolFamily;
+import java.net.UnixDomainSocketAddress;
+import java.nio.ByteBuffer;
+import java.nio.channels.ServerSocketChannel;
+import java.nio.channels.SocketChannel;
+import java.nio.file.Path;
+import java.util.UUID;
+
+import static java.nio.file.Files.deleteIfExists;
+import static org.assertj.core.util.Files.newTemporaryFile;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+public class UnixDomainSocketClientUnitTest {
+
+    @Test
+    public void givenSocketPath_shouldCreateUnixDomainSocketAddress() {
+        // given
+        File tempFile = newTemporaryFile();
+        Path socketPath = tempFile.toPath();
+
+        // when
+        UnixDomainSocketAddress address = new UnixDomainSocketClient().getAddress(socketPath);
+
+        // then
+        assertEquals(address.getPath(), socketPath);
+
+        // cleanup
+        tempFile.delete();
+    }
+
+    @Test
+    public void givenUnixDomainSocketAddress_shouldOpenSocketChannel() throws IOException {
+        // given
+        File tempFile = newTemporaryFile();
+        Path socketPath = tempFile.toPath();
+        deleteIfExists(socketPath);
+        UnixDomainSocketAddress address = UnixDomainSocketAddress.of(socketPath);
+
+        // bind address as a unix domain socket
+        ServerSocketChannel serverChannel = ServerSocketChannel.open(StandardProtocolFamily.UNIX);
+        serverChannel.bind(address);
+
+        // when
+        SocketChannel socketChannel = new UnixDomainSocketClient().openSocketChannel(address);
+
+        // then
+        assertTrue(socketChannel.isOpen());
+        assertEquals(socketChannel.getRemoteAddress(), address);
+
+        // cleanup
+        tempFile.delete();
+    }
+
+    @Test
+    public void givenSocketChannelAndMessage_shouldWriteMessage() throws IOException {
+        // given
+        SocketChannel socketChannel = Mockito.mock(SocketChannel.class);
+        String message = UUID.randomUUID().toString();
+        Mockito.when(socketChannel.write(Mockito.any(ByteBuffer.class)))
+          .thenAnswer(
+            (Answer<Integer>) invocationOnMock -> {
+              ((ByteBuffer) invocationOnMock.getArguments()[0]).position(message.getBytes().length);
+              return -1;
+            }
+          );
+
+        // when
+        new UnixDomainSocketClient().writeMessage(socketChannel, message);
+
+        // then
+        Mockito.verify(socketChannel, Mockito.times(1)).write(Mockito.any(ByteBuffer.class));
+    }
+}

core-java-modules/core-java-networking-3/src/test/java/com/baeldung/socket/UnixDomainSocketServerUnitTest.java

@@ -0,0 +1,50 @@
+package com.baeldung.socket;
+
+import org.junit.Test;
+
+import java.io.File;
+import java.io.IOException;
+import java.net.UnixDomainSocketAddress;
+import java.nio.channels.ServerSocketChannel;
+import java.nio.file.Path;
+
+import static java.nio.file.Files.deleteIfExists;
+import static org.assertj.core.util.Files.newTemporaryFile;
+import static org.junit.Assert.assertEquals;
+
+public class UnixDomainSocketServerUnitTest {
+
+    @Test
+    public void givenSocketPath_shouldCreateUnixDomainSocketAddress() {
+        // given
+        File tempFile = newTemporaryFile();
+        Path socketPath = tempFile.toPath();
+
+        // when
+        UnixDomainSocketAddress address = new UnixDomainSocketServer().getAddress(socketPath);
+
+        // then
+        assertEquals(address.getPath(), socketPath);
+
+        // cleanup
+        tempFile.delete();
+    }
+
+    @Test
+    public void givenUnixDomainSocketAddress_shouldCreateServerSocketChannel() throws IOException {
+        // given
+        File tempFile = newTemporaryFile();
+        Path socketPath = tempFile.toPath();
+        deleteIfExists(socketPath);
+        UnixDomainSocketAddress address = UnixDomainSocketAddress.of(socketPath);
+
+        // when
+        ServerSocketChannel serverSocketChannel = new UnixDomainSocketServer().createServerSocketChannel(address);
+
+        // then
+        assertEquals(serverSocketChannel.getLocalAddress(), address);
+
+        // cleanup
+        tempFile.delete();
+    }
+}

core-java-modules/core-java-os/pom.xml

@@ -45,6 +45,12 @@
 			<artifactId>grep4j</artifactId>
 			<version>${grep4j.version}</version>
 		</dependency>
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <version>${lombok.version}</version>
+            <scope>provided</scope>
+        </dependency>
 	</dependencies>
 
     <build>
@@ -69,7 +75,6 @@
     </build>
 
     <properties>
-        <commons-collections4.version>4.1</commons-collections4.version>
         <collections-generic.version>4.01</collections-generic.version>
         <asspectj.version>1.8.9</asspectj.version>
         <maven.compiler.source>1.9</maven.compiler.source>
@@ -77,6 +82,7 @@
         <guava.version>25.1-jre</guava.version>
         <unix4j.version>0.4</unix4j.version>
         <grep4j.version>1.8.7</grep4j.version>
+        <lombok.version>1.18.22</lombok.version>
     </properties>
 
 </project>

core-java-modules/core-java-os/src/test/java/com/baeldung/shell/JavaProcessUnitIntegrationTest.java

@@ -1,12 +1,23 @@
-package com.baeldung.java.shell;
+package com.baeldung.shell;
 
+import org.junit.After;
 import org.junit.Assert;
+import org.junit.Before;
 import org.junit.Test;
 
-import java.io.*;
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+import java.util.concurrent.TimeUnit;
 import java.util.function.Consumer;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
 public class JavaProcessUnitIntegrationTest {
     private static final boolean IS_WINDOWS = System.getProperty("os.name").toLowerCase().startsWith("windows");
 
@@ -29,6 +40,18 @@ public class JavaProcessUnitIntegrationTest {
 
     private String homeDirectory = System.getProperty("user.home");
 
+    private ExecutorService executorService;
+
+    @Before
+    public void setUp() {
+        executorService = Executors.newSingleThreadExecutor();
+    }
+
+    @After
+    public void tearDown() {
+        executorService.shutdown();
+    }
+
     @Test
     public void givenProcess_whenCreatingViaRuntime_shouldSucceed() throws Exception {
         Process process;
@@ -38,9 +61,13 @@ public class JavaProcessUnitIntegrationTest {
             process = Runtime.getRuntime().exec(String.format("sh -c ls %s", homeDirectory));
         }
         StreamGobbler streamGobbler = new StreamGobbler(process.getInputStream(), consumer);
-        Executors.newSingleThreadExecutor().submit(streamGobbler);
+
+        Future<?> future = executorService.submit(streamGobbler);
         int exitCode = process.waitFor();
-        Assert.assertEquals(0, exitCode);
+
+        // verify the stream output from the process
+        assertDoesNotThrow(() -> future.get(10, TimeUnit.SECONDS));
+        assertEquals(0, exitCode);
     }
 
     @Test
@@ -54,8 +81,12 @@ public class JavaProcessUnitIntegrationTest {
         builder.directory(new File(homeDirectory));
         Process process = builder.start();
         StreamGobbler streamGobbler = new StreamGobbler(process.getInputStream(), consumer);
-        Executors.newSingleThreadExecutor().submit(streamGobbler);
+
+        Future<?> future = executorService.submit(streamGobbler);
         int exitCode = process.waitFor();
-        Assert.assertEquals(0, exitCode);
+
+        // verify the stream output from the process
+        assertDoesNotThrow(() -> future.get(10, TimeUnit.SECONDS));
+        assertEquals(0, exitCode);
     }
 }

core-java-modules/core-java-regex/src/test/java/com/baeldung/regex/matcher/MatcherUnitTest.java

@@ -11,6 +11,9 @@ import org.junit.jupiter.api.Test;
 
 public class MatcherUnitTest {
 
+    private static final String STRING_INPUT = "test+";
+    private static final String REGEX = "\\+";
+
     @Test
     public void whenFindFourDigitWorks_thenCorrect() {
         Pattern stringPattern = Pattern.compile("\\d\\d\\d\\d");
@@ -60,4 +63,16 @@ public class MatcherUnitTest {
         assertTrue(m.matches());// matches will always return the same return
     }
 
+    @Test
+    public void whenUsingMatcher_thenReturnTrue() {
+        Pattern pattern = Pattern.compile(REGEX);
+        Matcher matcher = pattern.matcher(STRING_INPUT);
+        assertTrue(matcher.find());
+    }
+
+    @Test
+    public void whenUsingMatches_thenReturnFalse() {
+        assertFalse(Pattern.matches(REGEX, STRING_INPUT));
+    }
+
 }

core-java-modules/core-java-string-algorithms-3/src/test/java/com/baeldung/isuppercase/StringFirstCharacterUppercaseUnitTest.java

@@ -18,6 +18,7 @@ public class StringFirstCharacterUppercaseUnitTest {
     public void givenString_whenCheckingWithRegex_thenStringCapitalized() {
         String example = "Katie";
         String regEx = "[A-Z]\\w*";
+
         Assertions.assertTrue(example.matches(regEx));
     }
 

core-java-modules/core-java-string-conversions-2/README.md

@@ -9,4 +9,5 @@ This module contains articles about string conversions from/to another type.
 - [Converting String to BigDecimal in Java](https://www.baeldung.com/java-string-to-bigdecimal)
 - [Converting String to BigInteger in Java](https://www.baeldung.com/java-string-to-biginteger)
 - [Convert a String to Camel Case](https://www.baeldung.com/java-string-to-camel-case)
+- [Convert a ByteBuffer to String]
 - More articles: [[<-- prev]](/core-java-string-conversions)

core-java-modules/core-java-string-conversions-2/pom.xml

@@ -20,12 +20,6 @@
             <artifactId>guava</artifactId>
             <version>${guava.version}</version>
         </dependency>
-        <dependency>
-            <groupId>org.hamcrest</groupId>
-            <artifactId>hamcrest</artifactId>
-            <version>${hamcrest.version}</version>
-            <scope>test</scope>
-        </dependency>
         <dependency>
             <groupId>com.ibm.icu</groupId>
             <artifactId>icu4j</artifactId>

core-java-modules/core-java-string-conversions-2/src/test/java/com/baeldung/bytebuffertostring/ByteArrayToStringUnitTest.java

@@ -0,0 +1,44 @@
+package com.baeldung.bytebuffertostring;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.nio.ByteBuffer;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
+
+import org.junit.Test;
+
+public class ByteArrayToStringUnitTest {
+    private static Charset charset = StandardCharsets.UTF_8;
+    private static final String content = "baeldung";
+
+    @Test
+    public void convertUsingNewStringFromBufferArray_thenOK() {
+        // Allocate a ByteBuffer
+        ByteBuffer byteBuffer = ByteBuffer.wrap(content.getBytes());
+        if (byteBuffer.hasArray()) {
+            String newContent = new String(byteBuffer.array(), charset);
+            assertEquals(content, newContent);
+        }
+    }
+
+    @Test
+    public void convertUsingNewStringFromByteBufferGetBytes_thenOK() {
+        // Allocate a ByteBuffer
+        ByteBuffer byteBuffer = ByteBuffer.wrap(content.getBytes());
+        byte[] bytes = new byte[byteBuffer.remaining()];
+        byteBuffer.get(bytes);
+        String newContent = new String(bytes, charset);
+        assertEquals(content, newContent);
+    }
+
+    @Test
+    public void convertUsingCharsetDecode_thenOK() {
+        // Allocate a ByteBuffer
+        ByteBuffer byteBuffer = ByteBuffer.wrap(content.getBytes());
+        String newContent = charset.decode(byteBuffer)
+            .toString();
+        assertEquals(content, newContent);
+    }
+
+}

core-java-modules/core-java-string-conversions/pom.xml

@@ -35,12 +35,6 @@
             <artifactId>guava</artifactId>
             <version>${guava.version}</version>
         </dependency>
-        <dependency>
-            <groupId>org.hamcrest</groupId>
-            <artifactId>hamcrest</artifactId>
-            <version>${hamcrest.version}</version>
-            <scope>test</scope>
-        </dependency>
     </dependencies>
 
     <build>

core-java-modules/core-java-string-operations-2/README.md

@@ -12,5 +12,5 @@ This module contains articles about string operations.
 - [L-Trim and R-Trim Alternatives in Java](https://www.baeldung.com/java-trim-alternatives)
 - [Encode a String to UTF-8 in Java](https://www.baeldung.com/java-string-encode-utf-8)
 - [Guide to Character Encoding](https://www.baeldung.com/java-char-encoding)
-- [Convert Hex to ASCII in Java](https://www.baeldung.com/java-convert-hex-to-ascii) #remove additional readme file
+- [Convert Hex to ASCII in Java](https://www.baeldung.com/java-convert-hex-to-ascii)
 - More articles: [[<-- prev]](../core-java-string-operations)

core-java-modules/core-java-string-operations-2/pom.xml

@@ -45,12 +45,6 @@
             <artifactId>javax.el</artifactId>
             <version>${javax.el.version}</version>
         </dependency>
-        <dependency>
-            <groupId>org.hamcrest</groupId>
-            <artifactId>hamcrest</artifactId>
-            <version>${hamcrest.version}</version>
-            <scope>test</scope>
-        </dependency>
         <dependency>
             <groupId>org.openjdk.jmh</groupId>
             <artifactId>jmh-core</artifactId>

core-java-modules/core-java-string-operations-4/README.md

@@ -2,4 +2,5 @@
 
 - [Ignoring Commas in Quotes When Splitting a Comma-separated String](https://www.baeldung.com/java-split-string-commas)
 - [Compare Strings While Ignoring Whitespace in Java](https://www.baeldung.com/java-compare-string-whitespace)
+- [Concatenating Null Strings in Java](https://www.baeldung.com/java-concat-null-string)
 

core-java-modules/core-java-string-operations-4/src/main/java/com/baeldung/concatenation/ConcatenatingNull.java

@@ -0,0 +1,86 @@
+package com.baeldung.concatenation;
+
+import java.util.StringJoiner;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+public class ConcatenatingNull {
+
+    public static void main(String[] args) {
+        String[] values = { "Java ", null, "", "is ", "great!" };
+
+        concatenateUsingPlusOperator(values);
+        concatenateUsingHelperMethod(values);
+        concatenateUsingStringBuilder(values);
+        concatenateUsingJoin(values);
+        concatenateUsingStringJoiner(values);
+        concatenateUsingCollectorsJoining(values);
+        concatenateUsingStringConcat(values);
+    }
+
+    public static String concatenateUsingStringConcat(String[] values) {
+        String result = "";
+
+        for (String value : values) {
+            result = result.concat(getNonNullString(value));
+        }
+
+        return result;
+    }
+
+    public static String concatenateUsingCollectorsJoining(String[] values) {
+        String result = Stream.of(values).filter(value -> null != value).collect(Collectors.joining(""));
+
+        return result;
+    }
+
+    public static String concatenateUsingStringJoiner(String[] values) {
+        StringJoiner result = new StringJoiner("");
+
+        for (String value : values) {
+            result = result.add(getNonNullString(value));
+        }
+
+        return result.toString();
+    }
+
+    public static String concatenateUsingJoin(String[] values) {
+        String result = String.join("", values);
+
+        return result;
+    }
+
+    public static String concatenateUsingStringBuilder(String[] values) {
+        StringBuilder result = new StringBuilder();
+
+        for (String value : values) {
+            result = result.append(getNonNullString(value));
+        }
+
+        return result.toString();
+    }
+
+    public static String concatenateUsingHelperMethod(String[] values) {
+        String result = "";
+
+        for (String value : values) {
+            result = result + getNonNullString(value);
+        }
+
+        return result;
+    }
+
+    public static String concatenateUsingPlusOperator(String[] values) {
+        String result = "";
+
+        for (String value : values) {
+            result = result + (value == null ? "" : value);
+        }
+
+        return result;
+    }
+
+    private static String getNonNullString(String value) {
+        return value == null ? "" : value;
+    }
+}

core-java-modules/core-java-string-operations-4/src/test/java/com/baeldung/concatenation/ConcatenatingNullUnitTest.java

@@ -0,0 +1,59 @@
+package com.baeldung.concatenation;
+
+import static com.baeldung.concatenation.ConcatenatingNull.concatenateUsingCollectorsJoining;
+import static com.baeldung.concatenation.ConcatenatingNull.concatenateUsingHelperMethod;
+import static com.baeldung.concatenation.ConcatenatingNull.concatenateUsingJoin;
+import static com.baeldung.concatenation.ConcatenatingNull.concatenateUsingPlusOperator;
+import static com.baeldung.concatenation.ConcatenatingNull.concatenateUsingStringBuilder;
+import static com.baeldung.concatenation.ConcatenatingNull.concatenateUsingStringConcat;
+import static com.baeldung.concatenation.ConcatenatingNull.concatenateUsingStringJoiner;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.Test;
+
+public class ConcatenatingNullUnitTest {
+
+    String[] values = { "Java ", null, "", "is ", "great!" };
+
+    @Test
+    public void givenStringElementsWithNull_whenConcatenatedUsingPlus_thenNullIsIgnored() {
+        String result = concatenateUsingPlusOperator(values);
+        assertEquals("Java is great!", result);
+    }
+
+    @Test
+    public void givenStringElementsWithNull_whenConcatenatedUsingHelperMethod_thenNullIsIgnored() {
+        String result = concatenateUsingHelperMethod(values);
+        assertEquals("Java is great!", result);
+    }
+
+    @Test
+    public void givenStringElementsWithNull_whenConcatenatedUsingStringBuilder_thenNullIsIgnored() {
+        String result = concatenateUsingStringBuilder(values);
+        assertEquals("Java is great!", result);
+    }
+
+    @Test
+    public void givenStringElementsWithNull_whenConcatenatedUsingJoin_thenNullIsNotIgnored() {
+        String result = concatenateUsingJoin(values);
+        assertEquals("Java nullis great!", result);
+    }
+
+    @Test
+    public void givenStringElementsWithNull_whenConcatenatedUsingStringJoiner_thenNullIsIgnored() {
+        String result = concatenateUsingStringJoiner(values);
+        assertEquals("Java is great!", result);
+    }
+
+    @Test
+    public void givenStringElementsWithNull_whenConcatenatedUsingCollectorsJoining_thenNullIsIgnored() {
+        String result = concatenateUsingCollectorsJoining(values);
+        assertEquals("Java is great!", result);
+    }
+
+    @Test
+    public void givenStringElementsWithNull_whenConcatenatedUsingStringConcat_thenNullIsIgnored() {
+        String result = concatenateUsingStringConcat(values);
+        assertEquals("Java is great!", result);
+    }
+}

core-java-modules/pom.xml

@@ -90,7 +90,6 @@
         <module>core-java-lang-syntax-2</module>
         <module>core-java-networking</module>
         <module>core-java-networking-2</module>
-        <module>core-java-networking-3</module>
         <module>core-java-nio</module>
         <module>core-java-nio-2</module>
         <module>core-java-optional</module>

ethereum/pom.xml

@@ -144,12 +144,6 @@
             </exclusions>
             <scope>test</scope>
         </dependency>
-        <dependency>
-            <groupId>org.hamcrest</groupId>
-            <artifactId>hamcrest</artifactId>
-            <version>${hamcrest.version}</version>
-            <scope>test</scope>
-        </dependency>
         <dependency>
             <groupId>com.jayway.jsonpath</groupId>
             <artifactId>json-path</artifactId>

gson/pom.xml

@@ -61,10 +61,7 @@
     </build>
 
     <properties>
-        <!-- marshalling -->
         <gson.version>2.8.0</gson.version>
-        <!-- util -->
-        <commons-collections4.version>4.1</commons-collections4.version>
         <joda-time.version>2.9.6</joda-time.version>
     </properties>
 

guava-modules/guava-collections-list/pom.xml

@@ -45,9 +45,6 @@
     </build>
 
     <properties>
-        <!-- util -->
-        <commons-collections4.version>4.1</commons-collections4.version>
-        <!-- testing -->
         <java-hamcrest.version>2.0.0.0</java-hamcrest.version>
     </properties>
 

guava-modules/guava-collections/pom.xml

@@ -50,10 +50,7 @@
     </build>
 
     <properties>
-        <!-- util -->
-        <commons-collections4.version>4.1</commons-collections4.version>
         <jool.version>0.9.12</jool.version>
-        <!-- testing -->
         <java-hamcrest.version>2.0.0.0</java-hamcrest.version>
     </properties>
 

guest/core-kotlin/README.md

@@ -1,3 +0,0 @@
-### Relevant Articles:
-
-- [Kotlin vs Java](https://www.baeldung.com/kotlin/vs-java)

jackson-modules/jackson-conversions-2/README.md

@@ -11,4 +11,5 @@ This module contains articles about Jackson conversions.
 - [Jackson Streaming API](https://www.baeldung.com/jackson-streaming-api)
 - [Jackson: java.util.LinkedHashMap cannot be cast to X](https://www.baeldung.com/jackson-linkedhashmap-cannot-be-cast)
 - [Deserialize Snake Case to Camel Case With Jackson](https://www.baeldung.com/jackson-deserialize-snake-to-camel-case)
+- [Serialize and Deserialize Booleans as Integers With Jackson](https://www.baeldung.com/jackson-booleans-as-integers)
 - More articles: [[<-- prev]](../jackson-conversions)

jackson-modules/jackson-conversions-2/src/main/java/com/baeldung/jackson/booleanAsInt/Game.java

@@ -0,0 +1,49 @@
+package com.baeldung.jackson.booleanAsInt;
+
+public class Game {
+
+    private Long id;
+    private String name;
+    private Boolean paused;
+    private Boolean over;
+
+    public Game() {
+    }
+
+    public Game(Long id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    public Long getId() {
+        return this.id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return this.name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public Boolean isPaused() {
+        return paused;
+    }
+
+    public void setPaused(Boolean paused) {
+        this.paused = paused;
+    }
+
+    public Boolean isOver() {
+        return over;
+    }
+
+    public void setOver(Boolean over) {
+        this.over = over;
+    }
+}

jackson-modules/jackson-conversions-2/src/main/java/com/baeldung/jackson/booleanAsInt/GameAnnotatedByJsonFormat.java

@@ -0,0 +1,56 @@
+package com.baeldung.jackson.booleanAsInt;
+
+import com.fasterxml.jackson.annotation.JsonFormat;
+import com.fasterxml.jackson.annotation.JsonFormat.Shape;
+
+public class GameAnnotatedByJsonFormat {
+
+    private Long id;
+    private String name;
+
+    @JsonFormat(shape = Shape.NUMBER)
+    private boolean paused;
+
+    @JsonFormat(shape = Shape.NUMBER)
+    private boolean over;
+
+    public GameAnnotatedByJsonFormat() {
+    }
+
+    public GameAnnotatedByJsonFormat(Long id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    public Long getId() {
+        return this.id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return this.name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public boolean isPaused() {
+        return paused;
+    }
+
+    public void setPaused(boolean paused) {
+        this.paused = paused;
+    }
+
+    public boolean isOver() {
+        return over;
+    }
+
+    public void setOver(boolean over) {
+        this.over = over;
+    }
+}

jackson-modules/jackson-conversions-2/src/main/java/com/baeldung/jackson/booleanAsInt/GameAnnotatedByJsonSerializeDeserialize.java

@@ -0,0 +1,58 @@
+package com.baeldung.jackson.booleanAsInt;
+
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+import com.fasterxml.jackson.databind.annotation.JsonSerialize;
+
+public class GameAnnotatedByJsonSerializeDeserialize {
+
+    private Long id;
+    private String name;
+
+    @JsonSerialize(using = NumericBooleanSerializer.class)
+    @JsonDeserialize(using = NumericBooleanDeserializer.class)
+    private Boolean paused;
+
+    @JsonSerialize(using = NumericBooleanSerializer.class)
+    @JsonDeserialize(using = NumericBooleanDeserializer.class)
+    private Boolean over;
+
+    public GameAnnotatedByJsonSerializeDeserialize() {
+    }
+
+    public GameAnnotatedByJsonSerializeDeserialize(Long id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    public Long getId() {
+        return this.id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return this.name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public Boolean isPaused() {
+        return paused;
+    }
+
+    public void setPaused(Boolean paused) {
+        this.paused = paused;
+    }
+
+    public Boolean isOver() {
+        return over;
+    }
+
+    public void setOver(Boolean over) {
+        this.over = over;
+    }
+}

jackson-modules/jackson-conversions-2/src/main/java/com/baeldung/jackson/booleanAsInt/NumericBooleanDeserializer.java

@@ -0,0 +1,23 @@
+package com.baeldung.jackson.booleanAsInt;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.databind.DeserializationContext;
+import com.fasterxml.jackson.databind.JsonDeserializer;
+import java.io.IOException;
+
+public class NumericBooleanDeserializer extends JsonDeserializer<Boolean> {
+
+    @Override
+    public Boolean deserialize(JsonParser p, DeserializationContext ctxt)
+      throws IOException {
+        if ("1".equals(p.getText())) {
+            return Boolean.TRUE;
+        }
+        if ("0".equals(p.getText())) {
+            return Boolean.FALSE;
+        }
+        // for other than "1" or "0" throw exception by using Jackson internals
+        throw ctxt.weirdStringException(p.getText(), Boolean.class, "only \"1\" or \"0\" recognized");
+    }
+
+}

jackson-modules/jackson-conversions-2/src/main/java/com/baeldung/jackson/booleanAsInt/NumericBooleanSerializer.java

@@ -0,0 +1,15 @@
+package com.baeldung.jackson.booleanAsInt;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.JsonSerializer;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import java.io.IOException;
+
+public class NumericBooleanSerializer extends JsonSerializer<Boolean> {
+
+    @Override
+    public void serialize(Boolean value, JsonGenerator gen, SerializerProvider serializers)
+      throws IOException {
+        gen.writeString(value ? "1" : "0");
+    }
+}

jackson-modules/jackson-conversions-2/src/test/java/com/baeldung/jackson/booleanAsInt/BooleanAsIntegerUnitTest.java

@@ -0,0 +1,132 @@
+package com.baeldung.jackson.booleanAsInt;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.fasterxml.jackson.annotation.JsonFormat;
+import com.fasterxml.jackson.annotation.JsonFormat.Shape;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.exc.InvalidFormatException;
+import com.fasterxml.jackson.databind.module.SimpleModule;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+public class BooleanAsIntegerUnitTest {
+
+    private ObjectMapper mapper;
+
+    @BeforeEach
+    public void setup() {
+        mapper = new ObjectMapper();
+    }
+
+    @Test
+    public void givenBoolean_serializedAsInteger() throws Exception {
+        GameAnnotatedByJsonFormat
+          game = new GameAnnotatedByJsonFormat(1L, "My Game");
+        game.setPaused(true);
+        game.setOver(false);
+        String json = mapper.writeValueAsString(game);
+
+        assertThat(json)
+          .isEqualTo("{\"id\":1,\"name\":\"My Game\",\"paused\":1,\"over\":0}");
+    }
+
+    @Test
+    public void givenInteger_deserializedAsBooleanByDefault() throws Exception {
+        // Integer "1" and "0" values deserialized correctly out of the box.
+        // No configuration or @JsonFormat annotation needed.
+        String json = "{\"id\":1,\"name\":\"My Game\",\"paused\":1,\"over\":0}";
+        Game game = mapper.readValue(json, Game.class);
+
+        assertThat(game.isPaused()).isEqualTo(true);
+        assertThat(game.isOver()).isEqualTo(false);
+    }
+
+    @Test
+    public void givenBoolean_serializedAsIntegerGlobally() throws Exception {
+        // global configuration override for the type Boolean
+        mapper.configOverride(Boolean.class)
+          .setFormat(JsonFormat.Value.forShape(Shape.NUMBER));
+
+        Game game = new Game(1L, "My Game");
+        game.setPaused(true);
+        game.setOver(false);
+        String json = mapper.writeValueAsString(game);
+
+        assertThat(json)
+          .isEqualTo("{\"id\":1,\"name\":\"My Game\",\"paused\":1,\"over\":0}");
+    }
+
+    @Test
+    public void givenBooleanWithCustomSerializer_serializedAsNumericString() throws Exception {
+        GameAnnotatedByJsonSerializeDeserialize
+          game = new GameAnnotatedByJsonSerializeDeserialize(1L, "My Game");
+        game.setPaused(true);
+        game.setOver(false);
+        String json = mapper.writeValueAsString(game);
+
+        assertThat(json)
+          .isEqualTo("{\"id\":1,\"name\":\"My Game\",\"paused\":\"1\",\"over\":\"0\"}");
+    }
+
+    @Test
+    public void givenNumericStringWithCustomDeserializer_deserializedAsBoolean() throws Exception {
+        String json = "{\"id\":1,\"name\":\"My Game\",\"paused\":\"1\",\"over\":\"0\"}";
+        GameAnnotatedByJsonSerializeDeserialize
+          game = mapper.readValue(json, GameAnnotatedByJsonSerializeDeserialize.class);
+
+        assertThat(game.isPaused()).isEqualTo(true);
+        assertThat(game.isOver()).isEqualTo(false);
+    }
+
+    @Test
+    public void givenBooleanWithCustomSerializer_serializedAsNumericStringGlobally() throws Exception {
+        // setting serializers globally
+        SimpleModule module = new SimpleModule();
+        module.addSerializer(Boolean.class, new NumericBooleanSerializer());
+        mapper.registerModule(module);
+
+        Game game = new Game(1L, "My Game");
+        game.setPaused(true);
+        game.setOver(false);
+        String json = mapper.writeValueAsString(game);
+
+        assertThat(json)
+          .isEqualTo("{\"id\":1,\"name\":\"My Game\",\"paused\":\"1\",\"over\":\"0\"}");
+    }
+
+    @Test
+    public void givenNumericStringWithCustomDeserializer_deserializedAsBooleanGlobally() throws Exception {
+        // setting deserializers globally
+        SimpleModule module = new SimpleModule();
+        module.addDeserializer(Boolean.class, new NumericBooleanDeserializer());
+        mapper.registerModule(module);
+
+        String json = "{\"id\":1,\"name\":\"My Game\",\"paused\":\"1\",\"over\":\"0\"}";
+        Game game = mapper.readValue(json, Game.class);
+
+        assertThat(game.isPaused()).isEqualTo(true);
+        assertThat(game.isOver()).isEqualTo(false);
+    }
+
+    @Test
+    public void givenInvalidStringWithCustomDeserializer_throwsInvalidFormatException() {
+        // another number other than "1" or "0"
+        String json = "{\"id\":1,\"name\":\"My Game\",\"paused\":\"5\"}";
+        InvalidFormatException e = Assertions.assertThrows(
+          InvalidFormatException.class, () -> mapper.readValue(json, GameAnnotatedByJsonSerializeDeserialize.class)
+        );
+
+        assertThat(e.getValue()).isEqualTo("5");
+
+        // non-numeric string
+        String json2 = "{\"id\":1,\"name\":\"My Game\",\"paused\":\"xxx\"}";
+        InvalidFormatException e2 = Assertions.assertThrows(
+          InvalidFormatException.class, () -> mapper.readValue(json2, GameAnnotatedByJsonSerializeDeserialize.class)
+        );
+
+        assertThat(e2.getValue()).isEqualTo("xxx");
+    }
+
+}

java-collections-conversions-2/pom.xml

@@ -26,12 +26,6 @@
             <artifactId>modelmapper</artifactId>
             <version>${modelmapper.version}</version>
         </dependency>
-        <dependency>
-            <groupId>org.hamcrest</groupId>
-            <artifactId>hamcrest</artifactId>
-            <version>${hamcrest.version}</version>
-            <scope>test</scope>
-        </dependency>
         <dependency>
             <groupId>io.vavr</groupId>
             <artifactId>vavr</artifactId>

java-collections-conversions/pom.xml

@@ -38,8 +38,4 @@
         </resources>
     </build>
 
-    <properties>
-        <commons-collections4.version>4.4</commons-collections4.version>
-    </properties>
-
 </project>

java-collections-maps-3/pom.xml

@@ -30,7 +30,6 @@
     </dependencies>
 
     <properties>
-        <commons-collections4.version>4.1</commons-collections4.version>
         <spring.version>5.2.5.RELEASE</spring.version>
     </properties>
 

json/pom.xml

@@ -74,7 +74,6 @@
         <everit.json.schema.version>1.4.1</everit.json.schema.version>
         <fastjson.version>1.2.21</fastjson.version>
         <jsonb-api.version>1.0</jsonb-api.version>
-        <commons-collections4.version>4.1</commons-collections4.version>
         <yasson.version>1.0.1</yasson.version>
         <json.version>20171018</json.version>
         <gson.version>2.8.5</gson.version>

libraries-6/pom.xml

@@ -146,7 +146,6 @@
         <renjin.version>3.5-beta72</renjin.version>
         <rcaller.version>3.0</rcaller.version>
         <rserve.version>1.8.1</rserve.version>
-        <commons-collections4.version>4.4</commons-collections4.version>
         <libphonenumber.version>8.12.9</libphonenumber.version>
         <org.modelmapper.version>2.4.4</org.modelmapper.version>
     </properties>

libraries-apache-commons-collections/pom.xml

@@ -16,7 +16,7 @@
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-collections4</artifactId>
-            <version>${commons.collections.version}</version>
+            <version>${commons-collections4.version}</version>
         </dependency>
         <dependency>
             <groupId>org.hamcrest</groupId>
@@ -27,7 +27,6 @@
     </dependencies>
 
     <properties>
-        <commons.collections.version>4.1</commons.collections.version>
         <org.hamcrest.java-hamcrest.version>2.0.0.0</org.hamcrest.java-hamcrest.version>
     </properties>
 

libraries-data-db/pom.xml

@@ -63,7 +63,6 @@
         <dependency>
             <groupId>com.h2database</groupId>
             <artifactId>h2</artifactId>
-            <version>${h2.version}</version>
         </dependency>
         <!-- Hikari CP -->
         <dependency>

libraries-testing/pom.xml

@@ -118,7 +118,6 @@
             <version>${spring-mock-mvc.version}</version>
             <scope>test</scope>
         </dependency>
-        <!-- https://mvnrepository.com/artifact/org.hamcrest/java-hamcrest -->
         <dependency>
             <groupId>org.hamcrest</groupId>
             <artifactId>java-hamcrest</artifactId>
@@ -196,7 +195,6 @@
         <spring.version>4.3.8.RELEASE</spring.version>
         <spring-mock-mvc.version>4.1.1</spring-mock-mvc.version>
         <java-hamcrest.version>2.0.0.0</java-hamcrest.version>
-        <h2.version>1.4.200</h2.version>
         <dbunit.version>2.7.0</dbunit.version>
         <assertj-core.version>3.14.0</assertj-core.version>
         <maven-compiler-plugin.target>1.8</maven-compiler-plugin.target>

libraries/pom.xml

@@ -167,12 +167,6 @@
             <artifactId>google-oauth-client-jetty</artifactId>
             <version>${google-api.version}</version>
         </dependency>
-        <dependency>
-            <groupId>org.hamcrest</groupId>
-            <artifactId>hamcrest-all</artifactId>
-            <version>${hamcrest-all.version}</version>
-            <scope>test</scope>
-        </dependency>
     </dependencies>
 
     <repositories>
@@ -279,7 +273,6 @@
         <protonpack.version>1.15</protonpack.version>
         <google-api.version>1.23.0</google-api.version>
         <jets3t-version>0.9.4.0006L</jets3t-version>
-        <hamcrest-all.version>1.3</hamcrest-all.version>
         <javax.jdo.version>3.2.0-m7</javax.jdo.version>
         <datanucleus.version>5.1.1</datanucleus.version>
         <datanucleus-maven-plugin.version>5.0.2</datanucleus-maven-plugin.version>

linux-bash/text/README.md

@@ -1,4 +1,3 @@
 ### Relevant Articles:
 
-- [Linux Commands – Remove All Text After X](https://www.baeldung.com/linux/remove-text-after-x-in-file)
 - [Linux Commands for Appending Multiple Lines to a File](https://www.baeldung.com/linux/appending-multiple-lines-to-file2)

logging-modules/logback/pom.xml

@@ -74,4 +74,40 @@
         <javax.activation.version>1.1.1</javax.activation.version>
     </properties>
 
+    <profiles>
+        <profile>
+            <id>integration-lite-first</id>
+
+            <build>
+                <plugins>
+                    <plugin>
+                        <groupId>org.apache.maven.plugins</groupId>
+                        <artifactId>maven-surefire-plugin</artifactId>
+                        <configuration>
+                            <systemPropertyVariables>
+                                <logback.configurationFile>${project.basedir}/src/test/resources/logback-test.xml</logback.configurationFile>
+                            </systemPropertyVariables>
+                        </configuration>
+                    </plugin>
+                </plugins>
+            </build>
+        </profile>
+        <profile>
+            <id>integration-lite-second</id>
+
+            <build>
+                <plugins>
+                    <plugin>
+                        <groupId>org.apache.maven.plugins</groupId>
+                        <artifactId>maven-surefire-plugin</artifactId>
+                        <configuration>
+                            <systemPropertyVariables>
+                                <logback.configurationFile>${project.basedir}/src/test/resources/logback-test.xml</logback.configurationFile>
+                            </systemPropertyVariables>
+                        </configuration>
+                    </plugin>
+                </plugins>
+            </build>
+        </profile>
+    </profiles>
 </project>

parent-java/pom.xml

@@ -43,7 +43,6 @@
     <properties>
         <guava.version>31.0.1-jre</guava.version>
         <modelmapper.version>2.3.7</modelmapper.version>
-        <hamcrest.version>2.2</hamcrest.version>
     </properties>
 
 </project>

persistence-modules/core-java-persistence-2/pom.xml

@@ -44,7 +44,6 @@
     </dependencies>
 
     <properties>
-        <h2.version>1.4.200</h2.version>
         <mssql.driver.version>8.4.1.jre11</mssql.driver.version>
         <oracle.driver.version>10.2.0.4.0</oracle.driver.version>
         <mysql.driver.version>8.0.22</mysql.driver.version>

persistence-modules/core-java-persistence/pom.xml

@@ -55,7 +55,6 @@
     </dependencies>
 
     <properties>
-        <h2.version>1.4.200</h2.version>
         <commons-dbcp2.version>2.4.0</commons-dbcp2.version>
         <HikariCP.version>3.2.0</HikariCP.version>
         <c3p0.version>0.9.5.2</c3p0.version>

persistence-modules/hibernate-annotations/pom.xml

@@ -45,7 +45,6 @@
 
     <properties>
         <hibernate-core.version>5.4.7.Final</hibernate-core.version>
-        <h2.version>1.4.200</h2.version>
         <maven.deploy.skip>true</maven.deploy.skip>
         <spring-boot.version>2.1.7.RELEASE</spring-boot.version>
         <hibernate.core.version>5.4.7.Final</hibernate.core.version>

persistence-modules/hibernate-jpa/src/test/resources/hibernate-pessimistic-locking.properties

@@ -1,5 +1,5 @@
 hibernate.connection.driver_class=org.h2.Driver
-hibernate.connection.url=jdbc:h2:mem:mydb3;DB_CLOSE_DELAY=-1;LOCK_TIMEOUT=100;MVCC=FALSE
+hibernate.connection.url=jdbc:h2:mem:mydb3;DB_CLOSE_DELAY=-1;LOCK_TIMEOUT=100
 hibernate.connection.username=sa
 hibernate.connection.autocommit=true
 hibernate.dialect=org.hibernate.dialect.H2Dialect

persistence-modules/hibernate-mapping/pom.xml

@@ -69,6 +69,7 @@
     </dependencies>
 
     <properties>
+        <h2.version>1.4.197</h2.version> <!-- needs to be specified as it fails with parent's 1.4.200 -->
         <hibernate.version>5.4.12.Final</hibernate.version>
         <hibernate-types.version>2.10.4</hibernate-types.version>
         <hibernate-validator.version>6.0.16.Final</hibernate-validator.version>

persistence-modules/java-jpa-3/README.md

@@ -13,5 +13,4 @@ This module contains articles about the Java Persistence API (JPA) in Java.
 - [Returning an Auto-Generated Id with JPA](https://www.baeldung.com/jpa-get-auto-generated-id)
 - [How to Return Multiple Entities In JPA Query](https://www.baeldung.com/jpa-return-multiple-entities)
 - [Defining Unique Constraints in JPA](https://www.baeldung.com/jpa-unique-constraints)
-- [How to Check Field Existence in MongoDB?](https://www.baeldung.com/mongodb-check-field-exists)
 - [Connecting to a Specific Schema in JDBC](https://www.baeldung.com/jdbc-connect-to-schema)

persistence-modules/java-mongodb/README.md

@@ -11,3 +11,4 @@ This module contains articles about MongoDB in Java.
 - [Introduction to Morphia – Java ODM for MongoDB](https://www.baeldung.com/mongodb-morphia)
 - [MongoDB Aggregations Using Java](https://www.baeldung.com/java-mongodb-aggregations)
 - [BSON to JSON Document Conversion in Java](https://www.baeldung.com/java-convert-bson-to-json)
+- [How to Check Field Existence in MongoDB?](https://www.baeldung.com/mongodb-check-field-exists)

persistence-modules/jooq/pom.xml

@@ -45,7 +45,6 @@
 
     <properties>
         <jooq.version>3.13.4</jooq.version>
-        <h2.version>1.4.200</h2.version>
     </properties>
 
 </project>

persistence-modules/r2dbc/pom.xml

@@ -63,7 +63,6 @@
 
     <properties>
         <r2dbc-h2.version>0.8.1.RELEASE</r2dbc-h2.version>
-        <h2.version>1.4.200</h2.version>
     </properties>
 
 </project>

persistence-modules/r2dbc/src/test/resources/logback-test.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration scan="true" scanPeriod="15 seconds" debug="false">
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>[%d{ISO8601}]-[%thread] %-5level %logger - %msg%n</pattern>
+        </encoder>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT" />
+    </root>
+</configuration>

persistence-modules/spring-boot-persistence-2/src/test/resources/logback-test.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration scan="true" scanPeriod="15 seconds" debug="false">
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>[%d{ISO8601}]-[%thread] %-5level %logger - %msg%n</pattern>
+        </encoder>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT" />
+    </root>
+</configuration>

persistence-modules/spring-boot-persistence-h2/src/main/java/com/baeldung/h2db/lazy_load_no_trans/config/DatasourceProxyBeanPostProcessor.java

@@ -1,10 +1,7 @@
 package com.baeldung.h2db.lazy_load_no_trans.config;
 
 import net.ttddyy.dsproxy.listener.DataSourceQueryCountListener;
-import net.ttddyy.dsproxy.listener.logging.CommonsQueryLoggingListener;
-import net.ttddyy.dsproxy.listener.logging.DefaultQueryLogEntryCreator;
 import net.ttddyy.dsproxy.listener.logging.SLF4JLogLevel;
-import net.ttddyy.dsproxy.listener.logging.SLF4JQueryLoggingListener;
 import net.ttddyy.dsproxy.support.ProxyDataSource;
 import net.ttddyy.dsproxy.support.ProxyDataSourceBuilder;
 import org.aopalliance.intercept.MethodInterceptor;
@@ -49,7 +46,7 @@ public class DatasourceProxyBeanPostProcessor implements BeanPostProcessor {
             this.dataSource = ProxyDataSourceBuilder.create(dataSource)
                     .name("MyDS")
                     .multiline()
-                    .logQueryBySlf4j(SLF4JLogLevel.INFO)
+                    .logQueryBySlf4j(SLF4JLogLevel.DEBUG)
                     .listener(new DataSourceQueryCountListener())
                     .build();
         }

persistence-modules/spring-boot-persistence-h2/src/main/resources/application.properties

@@ -4,7 +4,7 @@ spring.datasource.username=sa
 spring.datasource.password=
 spring.jpa.defer-datasource-initialization=true
 spring.jpa.hibernate.ddl-auto=create-drop
-spring.jpa.show-sql=true
+spring.jpa.show-sql=false
 spring.jpa.properties.hibernate.format_sql=true
 spring.jpa.properties.hibernate.validator.apply_to_ddl=false
 #spring.jpa.properties.hibernate.check_nullability=true

persistence-modules/spring-boot-persistence-mongodb/src/test/resources/logback-test.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration scan="true" scanPeriod="15 seconds" debug="false">
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>[%d{ISO8601}]-[%thread] %-5level %logger - %msg%n</pattern>
+        </encoder>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT" />
+    </root>
+</configuration>

persistence-modules/spring-data-cassandra-reactive/src/test/resources/logback-test.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration scan="true" scanPeriod="15 seconds" debug="false">
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>[%d{ISO8601}]-[%thread] %-5level %logger - %msg%n</pattern>
+        </encoder>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT" />
+    </root>
+</configuration>