Merge pull request #18 from eugenp/master

update from eugenp/master

JGit/pom.xml

@@ -5,9 +5,9 @@
     <groupId>com.baeldung</groupId>
     <artifactId>JGit</artifactId>
     <version>1.0-SNAPSHOT</version>
+	<name>JGit</name>
     <packaging>jar</packaging>
     <url>http://maven.apache.org</url>
-	<name>JGit</name>
 
     <parent>
         <groupId>com.baeldung</groupId>

Twitter4J/pom.xml

@@ -2,8 +2,8 @@
     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
     <modelVersion>4.0.0</modelVersion>
     <artifactId>Twitter4J</artifactId>
-    <packaging>jar</packaging>
     <name>Twitter4J</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

akka-http/pom.xml

@@ -23,7 +23,7 @@
 		<dependency>
 			<groupId>com.typesafe.akka</groupId>
 			<artifactId>akka-stream_2.12</artifactId>
-			<version>2.5.11</version>
+			<version>${akka.stream.version}</version>
 		</dependency>
 		<dependency>
 			<groupId>com.typesafe.akka</groupId>

algorithms-miscellaneous-1/README.md

@@ -15,3 +15,5 @@
 - [Find Substrings That Are Palindromes in Java](https://www.baeldung.com/java-palindrome-substrings)
 - [Find the Longest Substring without Repeating Characters](https://www.baeldung.com/java-longest-substring-without-repeated-characters)
 - [Java Two Pointer Technique](https://www.baeldung.com/java-two-pointer-technique)
+- [Permutations of an Array in Java](https://www.baeldung.com/java-array-permutations)
+- [Implementing Simple State Machines with Java Enums](https://www.baeldung.com/java-enum-simple-state-machine)

algorithms-miscellaneous-2/pom.xml

@@ -68,7 +68,7 @@
             <plugin>
                 <groupId>org.codehaus.mojo</groupId>
                 <artifactId>cobertura-maven-plugin</artifactId>
-                <version>2.7</version>
+                <version>${cobertura-maven-plugin.version}</version>
                 <configuration>
                     <instrumentation>
                         <ignores>
@@ -91,6 +91,7 @@
         <org.jgrapht.ext.version>1.0.1</org.jgrapht.ext.version>
         <org.assertj.core.version>3.9.0</org.assertj.core.version>
         <commons-codec.version>1.11</commons-codec.version>
+        <cobertura-maven-plugin.version>2.7</cobertura-maven-plugin.version>
     </properties>
 
 </project>

animal-sniffer-mvn-plugin/pom.xml

@@ -3,9 +3,9 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.baeldung</groupId>
     <artifactId>animal-sniffer-mvn-plugin</artifactId>
-    <packaging>jar</packaging>
     <version>1.0-SNAPSHOT</version>
     <name>animal-sniffer-mvn-plugin</name>
+    <packaging>jar</packaging>
     <url>http://maven.apache.org</url>
 
     <parent>

annotations/pom.xml

@@ -3,8 +3,8 @@
     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>annotations</artifactId>
-    <packaging>pom</packaging>
     <name>annotations</name>
+    <packaging>pom</packaging>
     
     <parent>
         <artifactId>parent-modules</artifactId>

apache-avro/pom.xml

@@ -7,14 +7,6 @@
     <version>0.0.1-SNAPSHOT</version>
 	<name>apache-avro</name>
 
-    <properties>
-        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <compiler-plugin.version>3.5</compiler-plugin.version>
-        <avro.version>1.8.2</avro.version>
-        <java.version>1.8</java.version>
-        <slf4j.version>1.7.25</slf4j.version>
-    </properties>
-	
     <parent>
         <groupId>com.baeldung</groupId>
         <artifactId>parent-modules</artifactId>
@@ -85,4 +77,13 @@
             </plugin>
         </plugins>
     </build>
+
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <compiler-plugin.version>3.5</compiler-plugin.version>
+        <avro.version>1.8.2</avro.version>
+        <java.version>1.8</java.version>
+        <slf4j.version>1.7.25</slf4j.version>
+    </properties>
+	
 </project>

apache-curator/pom.xml

@@ -3,8 +3,8 @@
     <modelVersion>4.0.0</modelVersion>
     <artifactId>apache-curator</artifactId>
     <version>0.0.1-SNAPSHOT</version>
-    <packaging>jar</packaging>
 	<name>apache-curator</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

apache-geode/pom.xml

@@ -13,22 +13,6 @@
         <version>1.0.0-SNAPSHOT</version>
     </parent>
 
-    <properties>
-        <geode.core>1.6.0</geode.core>
-    </properties>
-    <build>
-        <plugins>
-            <plugin>
-                <groupId>org.apache.maven.plugins</groupId>
-                <artifactId>maven-compiler-plugin</artifactId>
-                <configuration>
-                    <source>1.8</source>
-                    <target>1.8</target>
-                </configuration>
-            </plugin>
-        </plugins>
-    </build>
-
     <dependencies>
         <dependency>
             <groupId>org.apache.geode</groupId>
@@ -38,8 +22,26 @@
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
-            <version>RELEASE</version>
+            <version>${junit.version}</version>
         </dependency>
     </dependencies>
     
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>${maven.compiler.source}</source>
+                    <target>${maven.compiler.target}</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+	
+    <properties>
+        <geode.core>1.6.0</geode.core>
+        <maven.compiler.source>1.8</maven.compiler.source>
+        <maven.compiler.target>1.8</maven.compiler.target>
+    </properties>
 </project>

apache-meecrowave/pom.xml

@@ -7,51 +7,58 @@
     <name>apache-meecrowave</name>
     <description>A sample REST API application with Meecrowave</description>
 
-    <properties>
-        <maven.compiler.source>1.8</maven.compiler.source>
-        <maven.compiler.target>1.8</maven.compiler.target>
-    </properties>
     <dependencies>
         <!-- https://mvnrepository.com/artifact/org.apache.meecrowave/meecrowave-core -->
         <dependency>
             <groupId>org.apache.meecrowave</groupId>
             <artifactId>meecrowave-core</artifactId>
-            <version>1.2.1</version>
+            <version>${meecrowave-core.version}</version>
         </dependency>
         <!-- https://mvnrepository.com/artifact/org.apache.meecrowave/meecrowave-jpa -->
         <dependency>
             <groupId>org.apache.meecrowave</groupId>
             <artifactId>meecrowave-jpa</artifactId>
-            <version>1.2.1</version>
+            <version>${meecrowave-jpa.version}</version>
         </dependency>
 
         <dependency>
             <groupId>com.squareup.okhttp3</groupId>
             <artifactId>okhttp</artifactId>
-            <version>3.10.0</version>
+            <version>${okhttp.version}</version>
         </dependency>
         <dependency>
             <groupId>org.apache.meecrowave</groupId>
             <artifactId>meecrowave-junit</artifactId>
-            <version>1.2.0</version>
+            <version>${meecrowave-junit.version}</version>
             <scope>test</scope>
         </dependency>
         <!-- https://mvnrepository.com/artifact/junit/junit -->
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
-            <version>4.10</version>
+            <version>${junit.version}</version>
             <scope>test</scope>
         </dependency>
-
     </dependencies>
+	
     <build>
         <plugins>
             <plugin>
                 <groupId>org.apache.meecrowave</groupId>
                 <artifactId>meecrowave-maven-plugin</artifactId>
-                <version>1.2.1</version>
+                <version>${meecrowave-maven-plugin.version}</version>
             </plugin>
         </plugins>
     </build>
+	
+    <properties>
+        <maven.compiler.source>1.8</maven.compiler.source>
+        <maven.compiler.target>1.8</maven.compiler.target>
+		<junit.version>4.10</junit.version>
+		<meecrowave-junit.version>1.2.0</meecrowave-junit.version>
+		<okhttp.version>3.10.0</okhttp.version>
+		<meecrowave-jpa.version>1.2.1</meecrowave-jpa.version>
+		<meecrowave-core.version>1.2.1</meecrowave-core.version>
+		<meecrowave-maven-plugin.version>1.2.1</meecrowave-maven-plugin.version>
+    </properties>
 </project>

apache-pulsar/pom.xml

@@ -11,12 +11,14 @@
         <dependency>
             <groupId>org.apache.pulsar</groupId>
             <artifactId>pulsar-client</artifactId>
-            <version>2.1.1-incubating</version>
+            <version>${pulsar-client.version}</version>
             <scope>compile</scope>
         </dependency>
     </dependencies>
+	
     <properties>
         <maven.compiler.target>1.8</maven.compiler.target>
         <maven.compiler.source>1.8</maven.compiler.source>
+		<pulsar-client.version>2.1.1-incubating</pulsar-client.version>
     </properties>
 </project>

apache-solrj/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>apache-solrj</artifactId>
     <version>0.0.1-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>apache-solrj</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

apache-spark/README.md

@@ -1,3 +1,4 @@
 ### Relevant articles
 
 - [Introduction to Apache Spark](http://www.baeldung.com/apache-spark)
+- [Building a Data Pipeline with Kafka, Spark Streaming and Cassandra](https://www.baeldung.com/kafka-spark-data-pipeline)

apache-spark/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>apache-spark</artifactId>
     <version>1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>apache-spark</name>
+    <packaging>jar</packaging>
     <url>http://maven.apache.org</url>
 
     <parent>
@@ -54,10 +54,10 @@
     	  	<plugin>
     			<groupId>org.apache.maven.plugins</groupId>
     			<artifactId>maven-compiler-plugin</artifactId>
-    			<version>3.2</version>
+    			<version>${maven-compiler-plugin.version}</version>
     			<configuration>
-      				<source>1.8</source>
+      				<source>${maven.compiler.source}</source>
-      				<target>1.8</target>
+      				<target>${maven.compiler.target}</target>
     			</configuration>
   			</plugin>
       		<plugin>
@@ -85,6 +85,9 @@
         <org.apache.spark.spark-streaming-kafka.version>2.3.0</org.apache.spark.spark-streaming-kafka.version>
         <com.datastax.spark.spark-cassandra-connector.version>2.3.0</com.datastax.spark.spark-cassandra-connector.version>
         <com.datastax.spark.spark-cassandra-connector-java.version>1.5.2</com.datastax.spark.spark-cassandra-connector-java.version>
+        <maven.compiler.source>1.8</maven.compiler.source>
+        <maven.compiler.target>1.8</maven.compiler.target>
+		<maven-compiler-plugin.version>3.2</maven-compiler-plugin.version>
     </properties>
 
 </project>

apache-velocity/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <version>0.1-SNAPSHOT</version>
     <artifactId>apache-velocity</artifactId>
-    <packaging>war</packaging>
     <name>apache-velocity</name>
+    <packaging>war</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

aws-lambda/pom.xml

@@ -5,8 +5,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>aws-lambda</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>aws-lambda</name>
+    <packaging>jar</packaging>
 
     <parent>
         <artifactId>parent-modules</artifactId>

aws/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>aws</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>aws</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

axon/pom.xml

@@ -36,7 +36,7 @@
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-autoconfigure</artifactId>
-            <version>2.1.1.RELEASE</version>
+            <version>${spring-boot.version}</version>
             <scope>compile</scope>
         </dependency>
 

azure/pom.xml

@@ -5,9 +5,9 @@
     <groupId>com.baeldung</groupId>
     <artifactId>azure</artifactId>
     <version>0.1</version>
-    <packaging>war</packaging>
     <name>azure</name>
     <description>Demo project for Spring Boot on Azure</description>
+    <packaging>war</packaging>
 
     <parent>
         <artifactId>parent-boot-2</artifactId>

blade/pom.xml

@@ -3,12 +3,12 @@
     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
 
     <modelVersion>4.0.0</modelVersion>
-    <artifactId>blade</artifactId>
-    <name>blade</name>
-
     <!-- WITH THIS mvn integration-test DOES WORK -->
     <groupId>com.baeldung</groupId>
+    <artifactId>blade</artifactId>
     <version>1.0.0-SNAPSHOT</version>
+    <name>blade</name>
+
 
     <!-- WITH THIS mvn integration-test DOESN'T WORK -->
     <!-- <parent> -->
@@ -17,35 +17,30 @@
     <!-- <version>1.0.0-SNAPSHOT</version> -->
     <!-- </parent> -->
 
-    <properties>
-        <maven.compiler.source>1.8</maven.compiler.source>
-        <maven.compiler.target>1.8</maven.compiler.target>
-    </properties>
-
     <dependencies>
         <dependency>
             <groupId>com.bladejava</groupId>
             <artifactId>blade-mvc</artifactId>
-            <version>2.0.14.RELEASE</version>
+            <version>${blade-mvc.version}</version>
         </dependency>
 
         <dependency>
             <groupId>org.webjars</groupId>
             <artifactId>bootstrap</artifactId>
-            <version>4.2.1</version>
+            <version>${bootstrap.version}</version>
         </dependency>
 
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-lang3</artifactId>
-            <version>3.8.1</version>
+            <version>${commons-lang3.version}</version>
         </dependency>
 
         <!-- PROVIDED -->
         <dependency>
             <groupId>org.projectlombok</groupId>
             <artifactId>lombok</artifactId>
-            <version>1.18.4</version>
+            <version>${lombok.version}</version>
             <scope>provided</scope>
         </dependency>
 
@@ -53,31 +48,31 @@
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
-            <version>4.12</version>
+            <version>${junit.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.assertj</groupId>
             <artifactId>assertj-core</artifactId>
-            <version>3.11.1</version>
+            <version>${assertj-core.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.apache.httpcomponents</groupId>
             <artifactId>httpclient</artifactId>
-            <version>4.5.6</version>
+            <version>${httpclient.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.apache.httpcomponents</groupId>
             <artifactId>httpmime</artifactId>
-            <version>4.5.6</version>
+            <version>${httpmime.version}</version>
             <scope>test</scope>
         </dependency>
         <dependency>
             <groupId>org.apache.httpcomponents</groupId>
             <artifactId>httpcore</artifactId>
-            <version>4.4.10</version>
+            <version>${httpcore.version}</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
@@ -88,6 +83,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-surefire-plugin</artifactId>
+                <version>${maven-surefire-plugin.version}</version>
                 <configuration>
                     <forkCount>3</forkCount>
                     <reuseForks>true</reuseForks>
@@ -100,7 +96,7 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-failsafe-plugin</artifactId>
-                <version>3.0.0-M3</version>
+                <version>${maven-failsafe-plugin.version}</version>
                 <configuration>
                     <includes>
                         <include>**/*LiveTest.java</include>
@@ -119,7 +115,7 @@
             <plugin>
                 <groupId>com.bazaarvoice.maven.plugins</groupId>
                 <artifactId>process-exec-maven-plugin</artifactId>
-                <version>0.7</version>
+                <version>${process-exec-maven-plugin.version}</version>
                 <executions>
                     <!--Start Blade -->
                     <execution>
@@ -177,13 +173,33 @@
                 </executions>
             </plugin>
             <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
+                <version>${maven-compiler-plugin.version}</version>
                 <configuration>
-                    <source>1.8</source>
+                    <source>${maven.compiler.source}</source>
-                    <target>1.8</target>
+                    <target>${maven.compiler.target}</target>
                     <encoding>UTF-8</encoding>
                 </configuration>
             </plugin>
         </plugins>
     </build>
+	
+    <properties>
+        <maven.compiler.source>1.8</maven.compiler.source>
+        <maven.compiler.target>1.8</maven.compiler.target>
+		<blade-mvc.version>2.0.14.RELEASE</blade-mvc.version>
+		<bootstrap.version>4.2.1</bootstrap.version>
+		<commons-lang3.version>3.8.1</commons-lang3.version>
+		<lombok.version>1.18.4</lombok.version>
+		<junit.version>4.12</junit.version>
+		<httpclient.version>4.5.6</httpclient.version>
+		<httpmime.version>4.5.6</httpmime.version>
+		<httpcore.version>4.4.10</httpcore.version>
+		<assertj-core.version>3.11.1</assertj-core.version>
+		<maven-failsafe-plugin.version>3.0.0-M3</maven-failsafe-plugin.version>
+		<process-exec-maven-plugin.version>0.7</process-exec-maven-plugin.version>
+		<maven-surefire-plugin.version>2.21.0</maven-surefire-plugin.version>
+		<maven-compiler-plugin.version>3.7.0</maven-compiler-plugin.version>
+    </properties>
 </project>

bootique/pom.xml

@@ -3,9 +3,9 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.baeldung.bootique</groupId>
     <artifactId>bootique</artifactId>
-    <packaging>jar</packaging>
     <version>1.0-SNAPSHOT</version>
     <name>bootique</name>
+    <packaging>jar</packaging>
     <url>http://maven.apache.org</url>
 
     <parent>

cas/cas-secured-app/pom.xml

@@ -3,9 +3,9 @@
     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>cas-secured-app</artifactId>
-    <packaging>jar</packaging>
     <name>cas-secured-app</name>
     <description>Demo project for CAS</description>
+    <packaging>jar</packaging>
 
     <parent>
         <artifactId>parent-boot-1</artifactId>

cdi/pom.xml

@@ -59,6 +59,7 @@
             <scope>test</scope>
         </dependency>
     </dependencies>
+	
     <properties>
         <cdi-api.version>2.0.SP1</cdi-api.version>
         <weld-se-core.version>3.0.5.Final</weld-se-core.version>

checker-plugin/pom.xml

@@ -3,9 +3,9 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.baeldung</groupId>
     <artifactId>checker-plugin</artifactId>
-    <packaging>jar</packaging>
     <version>1.0-SNAPSHOT</version>
     <name>checker-plugin</name>
+    <packaging>jar</packaging>
     <url>http://maven.apache.org</url>
 
     <parent>

core-groovy/src/main/groovy/com/baeldung/file/ReadFile.groovy

@@ -0,0 +1,107 @@
+package com.baeldung.file
+
+class ReadFile {
+
+    /**
+     * reads file content line by line using withReader and reader.readLine
+     * @param filePath
+     * @return
+     */
+    int readFileLineByLine(String filePath) {
+        File file = new File(filePath)
+        def line, noOfLines = 0;
+        file.withReader { reader ->
+            while ((line = reader.readLine())!=null)
+            {
+                println "${line}"
+                noOfLines++
+            }
+        }
+        return noOfLines
+    }
+
+    /**
+     * reads file content in list of lines
+     * @param filePath
+     * @return
+     */
+    List<String> readFileInList(String filePath) {
+        File file = new File(filePath)
+        def lines = file.readLines()
+        return lines
+    }
+
+    /**
+     * reads file content in string using File.text
+     * @param filePath
+     * @return
+     */
+    String readFileString(String filePath) {
+        File file = new File(filePath)
+        String fileContent = file.text
+        return fileContent
+    }
+
+    /**
+     * reads file content in string with encoding using File.getText
+     * @param filePath
+     * @return
+     */
+    String readFileStringWithCharset(String filePath) {
+        File file = new File(filePath)
+        String utf8Content = file.getText("UTF-8")
+        return utf8Content
+    }
+
+    /**
+     * reads content of binary file and returns byte array
+     * @param filePath
+     * @return
+     */
+    byte[] readBinaryFile(String filePath) {
+        File file = new File(filePath)
+        byte[] binaryContent = file.bytes
+        return binaryContent
+    }
+    
+    /**
+     * More Examples of reading a file 
+     * @return
+     */
+    def moreExamples() {
+        
+        //with reader with utf-8
+        new File("src/main/resources/utf8Content.html").withReader('UTF-8') { reader ->
+            def line
+            while ((line = reader.readLine())!=null) { 
+                println "${line}"
+            }
+        }
+        
+        //collect api
+        def list = new File("src/main/resources/fileContent.txt").collect {it}
+                
+        //as operator
+        def array = new File("src/main/resources/fileContent.txt") as String[]
+              
+        //eachline  
+        new File("src/main/resources/fileContent.txt").eachLine { line ->
+            println line
+        }
+        
+        //newInputStream with eachLine
+        def is = new File("src/main/resources/fileContent.txt").newInputStream()
+        is.eachLine {
+            println it
+        }
+        is.close()
+        
+        //withInputStream
+        new File("src/main/resources/fileContent.txt").withInputStream { stream ->
+            stream.eachLine { line ->
+                println line
+            }
+        }
+    }
+
+}

core-groovy/src/main/resources/fileContent.txt

@@ -0,0 +1,3 @@
+Line 1 : Hello World!!!
+Line 2 : This is a file content.
+Line 3 : String content

core-groovy/src/main/resources/utf8Content.html

@@ -0,0 +1,12 @@
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
+    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml">
+<meta charset="UTF-8">
+<body>
+<pre>
+ᚠᛇᚻ᛫ᛒᛦᚦ᛫ᚠᚱᚩᚠᚢᚱ᛫ᚠᛁᚱᚪ᛫ᚷᛖᚻᚹᛦᛚᚳᚢᛗ
+ᛋᚳᛖᚪᛚ᛫ᚦᛖᚪᚻ᛫ᛗᚪᚾᚾᚪ᛫ᚷᛖᚻᚹᛦᛚᚳ᛫ᛗᛁᚳᛚᚢᚾ᛫ᚻᛦᛏ᛫ᛞᚫᛚᚪᚾ
+ᚷᛁᚠ᛫ᚻᛖ᛫ᚹᛁᛚᛖ᛫ᚠᚩᚱ᛫ᛞᚱᛁᚻᛏᚾᛖ᛫ᛞᚩᛗᛖᛋ᛫ᚻᛚᛇᛏᚪᚾ
+</pre>
+</body>
+</html>

core-groovy/src/test/groovy/com/baeldung/file/ReadFileUnitTest.groovy

@@ -0,0 +1,70 @@
+package com.baeldung.file
+
+import spock.lang.Specification
+
+class ReadFileUnitTest extends Specification {
+
+    ReadFile readFile
+
+    void setup () {
+        readFile = new ReadFile()
+    }
+
+    def 'Should return number of lines in File using ReadFile.readFileLineByLine given filePath' () {
+        given:
+            def filePath = "src/main/resources/fileContent.txt"
+        when:
+            def noOfLines = readFile.readFileLineByLine(filePath)
+        then:
+            noOfLines
+            noOfLines instanceof Integer
+            assert noOfLines, 3
+    }
+    
+    def 'Should return File Content in list of lines using ReadFile.readFileInList given filePath' () {
+        given:
+            def filePath = "src/main/resources/fileContent.txt"
+        when:
+            def lines = readFile.readFileInList(filePath)
+        then:
+            lines
+            lines instanceof List<String>
+            assert lines.size(), 3
+    }
+    
+    def 'Should return file content in string using ReadFile.readFileString given filePath' () {
+        given:
+            def filePath = "src/main/resources/fileContent.txt"
+        when:
+            def fileContent = readFile.readFileString(filePath)
+        then:
+            fileContent
+            fileContent instanceof String
+            fileContent.contains("""Line 1 : Hello World!!!
+Line 2 : This is a file content.
+Line 3 : String content""")
+    
+    }
+
+    def 'Should return UTF-8 encoded file content in string using ReadFile.readFileStringWithCharset given filePath' () {
+        given:
+            def filePath = "src/main/resources/utf8Content.html"
+        when:
+            def encodedContent = readFile.readFileStringWithCharset(filePath)
+        then:
+            encodedContent
+            encodedContent instanceof String
+    }
+    
+    def 'Should return binary file content in byte array using ReadFile.readBinaryFile given filePath' () {
+        given:
+            def filePath = "src/main/resources/sample.png"
+        when:
+            def binaryContent = readFile.readBinaryFile(filePath)
+        then:
+            binaryContent
+            binaryContent instanceof byte[]
+            binaryContent.length == 329
+    }
+    
+}

core-java-10/pom.xml

@@ -3,9 +3,9 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.baeldung</groupId>
     <artifactId>core-java-10</artifactId>
-    <packaging>jar</packaging>
     <version>0.1.0-SNAPSHOT</version>
     <name>core-java-10</name>
+    <packaging>jar</packaging>
     <url>http://maven.apache.org</url>
 
     <parent>

core-java-11/README.md

@@ -3,3 +3,4 @@
 - [Java 11 Single File Source Code](https://www.baeldung.com/java-single-file-source-code)
 - [Java 11 Local Variable Syntax for Lambda Parameters](https://www.baeldung.com/java-var-lambda-params)
 - [Java 11 String API Additions](https://www.baeldung.com/java-11-string-api)
+- [Java 11 Nest Based Access Control](https://www.baeldung.com/java-nest-based-access-control)

core-java-11/pom.xml

@@ -3,9 +3,9 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.baeldung</groupId>
     <artifactId>core-java-11</artifactId>
-    <packaging>jar</packaging>
     <version>0.1.0-SNAPSHOT</version>
     <name>core-java-11</name>
+    <packaging>jar</packaging>
     <url>http://maven.apache.org</url>
 
     <parent>

core-java-8/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>core-java-8</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>core-java-8</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

core-java-8/src/test/java/com/baeldung/collectors/Java8CollectorsUnitTest.java

@@ -39,6 +39,7 @@ import static org.assertj.core.api.Assertions.assertThatThrownBy;
 public class Java8CollectorsUnitTest {
 
     private final List<String> givenList = Arrays.asList("a", "bb", "ccc", "dd");
+    private final List<String> listWithDuplicates = Arrays.asList("a", "bb", "c", "d", "bb");
 
     @Test
     public void whenCollectingToList_shouldCollectToList() throws Exception {
@@ -48,12 +49,19 @@ public class Java8CollectorsUnitTest {
     }
 
     @Test
-    public void whenCollectingToList_shouldCollectToSet() throws Exception {
+    public void whenCollectingToSet_shouldCollectToSet() throws Exception {
         final Set<String> result = givenList.stream().collect(toSet());
 
         assertThat(result).containsAll(givenList);
     }
 
+    @Test
+    public void givenContainsDuplicateElements_whenCollectingToSet_shouldAddDuplicateElementsOnlyOnce() throws Exception {
+        final Set<String> result = listWithDuplicates.stream().collect(toSet());
+
+        assertThat(result).hasSize(4);
+    }
+
     @Test
     public void whenCollectingToCollection_shouldCollectToCollection() throws Exception {
         final List<String> result = givenList.stream().collect(toCollection(LinkedList::new));
@@ -83,6 +91,13 @@ public class Java8CollectorsUnitTest {
         assertThat(result).containsEntry("a", 1).containsEntry("bb", 2).containsEntry("ccc", 3).containsEntry("dd", 2);
     }
 
+    @Test
+    public void givenContainsDuplicateElements_whenCollectingToMap_shouldThrowException() throws Exception {
+        assertThatThrownBy(() -> {
+            listWithDuplicates.stream().collect(toMap(Function.identity(), String::length));
+        }).isInstanceOf(IllegalStateException.class);
+    }
+
     @Test
     public void whenCollectingAndThen_shouldCollect() throws Exception {
         final List<String> result = givenList.stream().collect(collectingAndThen(toList(), ImmutableList::copyOf));

core-java-8/src/test/java/com/baeldung/java8/lambda/methodreference/MethodReferenceUnitTest.java

@@ -5,9 +5,10 @@ import java.util.Arrays;
 import java.util.List;
 import java.util.function.BiFunction;
 
+import org.apache.commons.lang3.StringUtils;
 import org.junit.Test;
 
-public class MethodReferenceExamples {
+public class MethodReferenceUnitTest {
 
     private static <T> void doNothingAtAll(Object... o) {
     }
@@ -17,10 +18,8 @@ public class MethodReferenceExamples {
     @Test
     public void referenceToStaticMethod() {
         List<String> messages = Arrays.asList("Hello", "Baeldung", "readers!");
-        messages.forEach((word) -> {
+        messages.forEach(word -> StringUtils.capitalize(word));
-            System.out.println(word);
+        messages.forEach(StringUtils::capitalize);
-        });
-        messages.forEach(System.out::println);
     }
 
     @Test
@@ -63,7 +62,7 @@ public class MethodReferenceExamples {
     @Test
     public void limitationsAndAdditionalExamples() {
         createBicyclesList().forEach(b -> System.out.printf("Bike brand is '%s' and frame size is '%d'%n", b.getBrand(), b.getFrameSize()));
-        createBicyclesList().forEach((o) -> MethodReferenceExamples.doNothingAtAll(o));
+        createBicyclesList().forEach((o) -> MethodReferenceUnitTest.doNothingAtAll(o));
     }
 
     private List<Bicycle> createBicyclesList() {

core-java-9/README.md

@@ -26,3 +26,4 @@
 - [Initialize a HashMap in Java](https://www.baeldung.com/java-initialize-hashmap)
 - [Java 9 Platform Logging API](https://www.baeldung.com/java-9-logging-api)
 - [Guide to java.lang.Process API](https://www.baeldung.com/java-process-api)
+- [Immutable Set in Java](https://www.baeldung.com/java-immutable-set)

core-java-9/compile-aot.sh

@@ -0,0 +1,5 @@
+#!/usr/bin/env bash
+cd src/main/java
+javac com/baeldung/java9/aot/JaotCompilation.java
+jaotc --output jaotCompilation.so com/baeldung/java9/aot/JaotCompilation.class
+

core-java-9/run-aot.sh

@@ -0,0 +1,3 @@
+#!/usr/bin/env bash
+cd src/main/java
+java -XX:AOTLibrary=./jaotCompilation.so com/baeldung/java9/aot/JaotCompilation

core-java-9/src/main/java/com/baeldung/java9/aot/JaotCompilation.java

@@ -0,0 +1,12 @@
+package com.baeldung.java9.aot;
+
+public class JaotCompilation {
+
+    public static void main(String[] argv) {
+        System.out.println(message());
+    }
+
+    public static String message() {
+        return "The JAOT compiler says 'Hello'";
+    }
+}

core-java-arrays/README.md

@@ -14,3 +14,4 @@
 - [Array Operations in Java](http://www.baeldung.com/java-common-array-operations)
 - [Intersection Between two Integer Arrays](https://www.baeldung.com/java-array-intersection)
 - [Sorting Arrays in Java](https://www.baeldung.com/java-sorting-arrays)
+- [Convert a Float to a Byte Array in Java](https://www.baeldung.com/java-convert-float-to-byte-array)

core-java-arrays/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>core-java-arrays</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>core-java-arrays</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

core-java-collections-list/pom.xml

@@ -3,8 +3,8 @@
     <modelVersion>4.0.0</modelVersion>
     <artifactId>core-java-collections-list</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>core-java-collections-list</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>
@@ -40,17 +40,17 @@
         <dependency>
             <groupId>net.sf.trove4j</groupId>
             <artifactId>trove4j</artifactId>
-            <version>3.0.2</version>
+            <version>${trove4j.version}</version>
         </dependency>
         <dependency>
             <groupId>it.unimi.dsi</groupId>
             <artifactId>fastutil</artifactId>
-            <version>8.1.0</version>
+            <version>${fastutil.version}</version>
         </dependency>
         <dependency>
             <groupId>colt</groupId>
             <artifactId>colt</artifactId>
-            <version>1.2.0</version>
+            <version>${colt.version}</version>
         </dependency>
     </dependencies>
 
@@ -60,5 +60,8 @@
         <avaitility.version>1.7.0</avaitility.version>
         <assertj.version>3.11.1</assertj.version>
         <lombok.version>1.16.12</lombok.version>
+		<trove4j.version>3.0.2</trove4j.version>
+		<fastutil.version>8.1.0</fastutil.version>
+		<colt.version>1.2.0</colt.version>
     </properties>
 </project>

core-java-collections/README.md

@@ -31,3 +31,4 @@
 - [A Guide to EnumMap](https://www.baeldung.com/java-enum-map)
 - [A Guide to Iterator in Java](http://www.baeldung.com/java-iterator)
 - [Differences Between HashMap and Hashtable](https://www.baeldung.com/hashmap-hashtable-differences)
+- [Java ArrayList vs Vector](https://www.baeldung.com/java-arraylist-vs-vector)

core-java-collections/pom.xml

@@ -3,8 +3,8 @@
     <modelVersion>4.0.0</modelVersion>
     <artifactId>core-java-collections</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>core-java-collections</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>
@@ -54,7 +54,7 @@
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-exec</artifactId>
-            <version>1.3</version>
+            <version>${commons-exec.version}</version>
         </dependency>
         <dependency>
             <groupId>org.projectlombok</groupId>
@@ -74,5 +74,6 @@
         <assertj.version>3.11.1</assertj.version>
         <eclipse.collections.version>7.1.0</eclipse.collections.version>
         <lombok.version>1.16.12</lombok.version>
+		<commons-exec.version>1.3</commons-exec.version>
     </properties>
 </project>

core-java-collections/src/main/java/com/baeldung/charstack/CharStack.java

@@ -0,0 +1,37 @@
+package com.baeldung.charstack;
+
+import java.util.Iterator;
+import java.util.LinkedList;
+
+public class CharStack {
+
+    private LinkedList<Character> items;
+
+    public CharStack() {
+        this.items = new LinkedList<Character>();
+    }
+
+    public void push(Character item) {
+        items.push(item);
+    }
+
+    public Character peek() {
+        return items.getFirst();
+    }
+
+    public Character pop() {
+
+        Iterator<Character> iter = items.iterator();
+        Character item = iter.next();
+        if (item != null) {
+            iter.remove();
+            return item;
+        }
+        return null;
+    }
+
+    public int size() {
+        return items.size();
+    }
+
+}

core-java-collections/src/main/java/com/baeldung/charstack/CharStackWithArray.java

@@ -0,0 +1,48 @@
+package com.baeldung.charstack;
+
+public class CharStackWithArray {
+
+    private char[] elements;
+    private int size;
+
+    public CharStackWithArray() {
+        size = 0;
+        elements = new char[4];
+    }
+
+    public int size() {
+        return size;
+    }
+
+    public char peek() {
+        if (size == 0) {
+            throw new EmptyStackException();
+        }
+        return elements[size - 1];
+    }
+
+    public char pop() {
+        if (size == 0) {
+            throw new EmptyStackException();
+        }
+
+        return elements[--size];
+    }
+
+    public void push(char item) {
+        ensureCapacity(size + 1);
+        elements[size] = item;
+        size++;
+    }
+
+    private void ensureCapacity(int newSize) {
+        char newBiggerArray[];
+
+        if (elements.length < newSize) {
+            newBiggerArray = new char[elements.length * 2];
+            System.arraycopy(elements, 0, newBiggerArray, 0, size);
+            elements = newBiggerArray;
+        }
+    }
+
+}

core-java-collections/src/main/java/com/baeldung/charstack/EmptyStackException.java

@@ -0,0 +1,9 @@
+package com.baeldung.charstack;
+
+public class EmptyStackException extends RuntimeException {
+
+    public EmptyStackException() {
+        super("Stack is empty");
+    }
+
+}

core-java-collections/src/main/java/com/baeldung/queueInterface/CustomBaeldungQueue.java

@@ -1,4 +1,4 @@
-package com.baeldung.queueinterface;
+package com.baeldung.queueInterface;
 
 import java.util.AbstractQueue;
 import java.util.Iterator;

core-java-collections/src/test/java/com/baeldung/charstack/CharStackUnitTest.java

@@ -0,0 +1,50 @@
+package com.baeldung.charstack;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.jupiter.api.Test;
+
+public class CharStackUnitTest {
+
+    @Test
+    public void whenCharStackIsCreated_thenItHasSize0() {
+
+        CharStack charStack = new CharStack();
+
+        assertEquals(0, charStack.size());
+    }
+
+    @Test
+    public void givenEmptyCharStack_whenElementIsPushed_thenStackSizeisIncreased() {
+
+        CharStack charStack = new CharStack();
+
+        charStack.push('A');
+
+        assertEquals(1, charStack.size());
+    }
+
+    @Test
+    public void givenCharStack_whenElementIsPoppedFromStack_thenElementIsRemovedAndSizeChanges() {
+
+        CharStack charStack = new CharStack();
+        charStack.push('A');
+
+        char element = charStack.pop();
+
+        assertEquals('A', element);
+        assertEquals(0, charStack.size());
+    }
+
+    @Test
+    public void givenCharStack_whenElementIsPeeked_thenElementIsNotRemovedAndSizeDoesNotChange() {
+        CharStack charStack = new CharStack();
+        charStack.push('A');
+
+        char element = charStack.peek();
+
+        assertEquals('A', element);
+        assertEquals(1, charStack.size());
+    }
+
+}

core-java-collections/src/test/java/com/baeldung/charstack/CharStackUsingJavaUnitTest.java

@@ -0,0 +1,53 @@
+package com.baeldung.charstack;
+
+import static org.junit.Assert.assertEquals;
+
+import java.util.Stack;
+
+import org.junit.jupiter.api.Test;
+
+public class CharStackUsingJavaUnitTest {
+
+    @Test
+    public void whenCharStackIsCreated_thenItHasSize0() {
+
+        Stack<Character> charStack = new Stack<>();
+
+        assertEquals(0, charStack.size());
+    }
+
+    @Test
+    public void givenEmptyCharStack_whenElementIsPushed_thenStackSizeisIncreased() {
+
+        Stack<Character> charStack = new Stack<>();
+
+        charStack.push('A');
+
+        assertEquals(1, charStack.size());
+    }
+
+    @Test
+    public void givenCharStack_whenElementIsPoppedFromStack_thenElementIsRemovedAndSizeChanges() {
+
+        Stack<Character> charStack = new Stack<>();
+        charStack.push('A');
+
+        char element = charStack.pop();
+
+        assertEquals('A', element);
+        assertEquals(0, charStack.size());
+    }
+
+    @Test
+    public void givenCharStack_whenElementIsPeeked_thenElementIsNotRemovedAndSizeDoesNotChange() {
+
+        Stack<Character> charStack = new Stack<>();
+        charStack.push('A');
+
+        char element = charStack.peek();
+
+        assertEquals('A', element);
+        assertEquals(1, charStack.size());
+    }
+
+}

core-java-collections/src/test/java/com/baeldung/charstack/CharStackWithArrayUnitTest.java

@@ -0,0 +1,65 @@
+package com.baeldung.charstack;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.jupiter.api.Test;
+
+public class CharStackWithArrayUnitTest {
+
+    @Test
+    public void whenCharStackIsCreated_thenItHasSize0() {
+
+        CharStackWithArray charStack = new CharStackWithArray();
+
+        assertEquals(0, charStack.size());
+    }
+
+    @Test
+    public void givenEmptyCharStack_whenElementIsPushed_thenStackSizeisIncreased() {
+
+        CharStackWithArray charStack = new CharStackWithArray();
+
+        charStack.push('A');
+
+        assertEquals(1, charStack.size());
+    }
+
+    @Test
+    public void givenEmptyCharStack_when5ElementIsPushed_thenStackSizeis() {
+
+        CharStackWithArray charStack = new CharStackWithArray();
+
+        charStack.push('A');
+        charStack.push('B');
+        charStack.push('C');
+        charStack.push('D');
+        charStack.push('E');
+
+        assertEquals(5, charStack.size());
+    }
+
+    @Test
+    public void givenCharStack_whenElementIsPoppedFromStack_thenElementIsRemovedAndSizeChanges() {
+
+        CharStackWithArray charStack = new CharStackWithArray();
+        charStack.push('A');
+
+        char element = charStack.pop();
+
+        assertEquals('A', element);
+        assertEquals(0, charStack.size());
+    }
+
+    @Test
+    public void givenCharStack_whenElementIsPeeked_thenElementIsNotRemovedAndSizeDoesNotChange() {
+
+        CharStackWithArray charStack = new CharStackWithArray();
+        charStack.push('A');
+
+        char element = charStack.peek();
+
+        assertEquals('A', element);
+        assertEquals(1, charStack.size());
+    }
+
+}

core-java-collections/src/test/java/com/baeldung/queueinterface/CustomBaeldungQueueUnitTest.java

@@ -1,4 +1,4 @@
-package com.baeldung.queueinterface;
+package com.baeldung.queueInterface;
 
 import org.junit.Before;
 import org.junit.Test;

core-java-collections/src/test/java/com/baeldung/queueinterface/PriorityQueueUnitTest.java

@@ -1,4 +1,4 @@
-package com.baeldung.queueinterface;
+package com.baeldung.queueInterface;
 
 import org.junit.Before;
 import org.junit.Test;

core-java-concurrency-advanced/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>core-java-concurrency-advanced</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>core-java-concurrency-advanced</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

core-java-concurrency-basic/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>core-java-concurrency-basic</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>core-java-concurrency-basic</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

core-java-concurrency-collections/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>core-java-concurrency-collections</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>core-java-concurrency-collections</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

core-java-io/README.md

@@ -38,3 +38,5 @@
 - [How to Get the File Extension of a File in Java](http://www.baeldung.com/java-file-extension)
 - [Getting a File’s Mime Type in Java](http://www.baeldung.com/java-file-mime-type)
 - [Create a Directory in Java](https://www.baeldung.com/java-create-directory)
+- [How to Write to a CSV File in Java](https://www.baeldung.com/java-csv)
+- [List Files in a Directory in Java](https://www.baeldung.com/java-list-directory-files)

core-java-io/pom.xml

@@ -3,8 +3,8 @@
     <modelVersion>4.0.0</modelVersion>
     <artifactId>core-java-io</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>core-java-io</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

core-java-lang-oop/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>core-java-lang-oop</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>core-java-lang-oop</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

core-java-lang-oop/src/main/java/com/baeldung/markerinterface/DeletableShape.java

@@ -0,0 +1,5 @@
+package com.baeldung.markerinterface;
+
+public interface DeletableShape extends Shape {
+
+}

core-java-lang-oop/src/main/java/com/baeldung/markerinterface/Rectangle.java

@@ -0,0 +1,22 @@
+package com.baeldung.markerinterface;
+
+public class Rectangle implements DeletableShape {
+
+    private double width;
+    private double height;
+
+    public Rectangle(double width, double height) {
+        this.width = width;
+        this.height = height;
+    }
+
+    @Override
+    public double getArea() {
+        return width * height;
+    }
+
+    @Override
+    public double getCircumference() {
+        return 2 * (width + height);
+    }
+}

core-java-lang-oop/src/main/java/com/baeldung/markerinterface/Shape.java

@@ -0,0 +1,6 @@
+package com.baeldung.markerinterface;
+
+public interface Shape {
+    double getArea();
+    double getCircumference();
+}

core-java-lang-oop/src/main/java/com/baeldung/markerinterface/ShapeDao.java

@@ -0,0 +1,14 @@
+package com.baeldung.markerinterface;
+
+public class ShapeDao {
+
+    public boolean delete(Object object) {
+        if (!(object instanceof DeletableShape)) {
+            return false;
+        }
+        // Calling the code that deletes the entity from the database
+
+        return true;
+    }
+
+}

core-java-lang-oop/src/test/java/com/baeldung/markerinterface/MarkerInterfaceUnitTest.java

@@ -0,0 +1,26 @@
+package com.baeldung.markerinterface;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.jupiter.api.Test;
+
+public class MarkerInterfaceUnitTest {
+
+    @Test
+    public void givenDeletableObjectThenTrueReturned() {
+        ShapeDao shapeDao = new ShapeDao();
+        Object rectangle = new Rectangle(2, 3);
+
+        boolean result = shapeDao.delete(rectangle);
+        assertEquals(true, result);
+    }
+    
+    @Test
+    public void givenNonDeletableObjectThenFalseReturned() {
+        ShapeDao shapeDao = new ShapeDao();
+        Object object = new Object();
+
+        boolean result = shapeDao.delete(object);
+        assertEquals(false, result);
+    }
+}

core-java-lang-syntax/README.md

@@ -17,3 +17,4 @@
 - [Java Switch Statement](https://www.baeldung.com/java-switch)
 - [The Modulo Operator in Java](https://www.baeldung.com/modulo-java)
 - [Ternary Operator In Java](https://www.baeldung.com/java-ternary-operator)
+- [Java instanceof Operator](https://www.baeldung.com/java-instanceof)

core-java-lang-syntax/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>core-java-lang-syntax</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>core-java-lang-syntax</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

core-java-lang/README.md

@@ -35,3 +35,9 @@
 - [Retrieving a Class Name in Java](https://www.baeldung.com/java-class-name)
 - [Java Compound Operators](https://www.baeldung.com/java-compound-operators)
 - [Guide to Java Packages](https://www.baeldung.com/java-packages)
+- [The Java Native Keyword and Methods](https://www.baeldung.com/java-native)
+- [If-Else Statement in Java](https://www.baeldung.com/java-if-else)
+- [Control Structures in Java](https://www.baeldung.com/java-control-structures)
+- [Java Interfaces](https://www.baeldung.com/java-interfaces)
+- [Attaching Values to Java Enum](https://www.baeldung.com/java-enum-values)
+- [Variable Scope in Java](https://www.baeldung.com/java-variable-scope)

core-java-lang/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>core-java-lang</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>core-java-lang</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

core-java-lang/src/main/java/com/baeldung/scope/BracketScopeExample.java

@@ -1,4 +1,4 @@
-package org.baeldung.variable.scope.examples;
+package com.baeldung.scope;
 
 public class BracketScopeExample {
 

core-java-lang/src/main/java/com/baeldung/scope/ClassScopeExample.java

@@ -1,4 +1,4 @@
-package org.baeldung.variable.scope.examples;
+package com.baeldung.scope;
 
 public class ClassScopeExample {
 

core-java-lang/src/main/java/com/baeldung/scope/LoopScopeExample.java

@@ -1,4 +1,4 @@
-package org.baeldung.variable.scope.examples;
+package com.baeldung.scope;
 
 import java.util.Arrays;
 import java.util.List;

core-java-lang/src/main/java/com/baeldung/scope/MethodScopeExample.java

@@ -1,4 +1,4 @@
-package org.baeldung.variable.scope.examples;
+package com.baeldung.scope;
 
 public class MethodScopeExample {
 

core-java-lang/src/main/java/com/baeldung/scope/NestedScopesExample.java

@@ -1,4 +1,4 @@
-package org.baeldung.variable.scope.examples;
+package com.baeldung.scope;
 
 public class NestedScopesExample {
 

core-java-lang/src/test/java/com/baeldung/java/enumiteration/EnumIterationExamples.java

@@ -1,18 +1,43 @@
 package com.baeldung.java.enumiteration;
 
+import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.EnumSet;
+import java.util.List;
+
 
 public class EnumIterationExamples {
 	public static void main(String[] args) {
-		System.out.println("Enum iteration using forEach:");
+		System.out.println("Enum iteration using EnumSet:");
 		EnumSet.allOf(DaysOfWeekEnum.class).forEach(day -> System.out.println(day));
 
 		System.out.println("Enum iteration using Stream:");
 		DaysOfWeekEnum.stream().filter(d -> d.getTypeOfDay().equals("off")).forEach(System.out::println);
 
-		System.out.println("Enum iteration using for loop:");
+		System.out.println("Enum iteration using a for loop:");
 		for (DaysOfWeekEnum day : DaysOfWeekEnum.values()) {
 			System.out.println(day);
 		}
+		
+		System.out.println("Enum iteration using Arrays.asList():");
+	        Arrays.asList(DaysOfWeekEnum.values()).forEach(day -> System.out.println(day));
+	        
+	        System.out.println("Add Enum values to ArrayList:");
+	        List<DaysOfWeekEnum> days = new ArrayList<>();
+                days.add(DaysOfWeekEnum.FRIDAY);
+                days.add(DaysOfWeekEnum.SATURDAY);
+                days.add(DaysOfWeekEnum.SUNDAY);
+                for (DaysOfWeekEnum day : days) {
+                    System.out.println(day);
+                }
+                System.out.println("Remove SATURDAY from the list:");
+                days.remove(DaysOfWeekEnum.SATURDAY); 
+                if (!days.contains(DaysOfWeekEnum.SATURDAY)) { 
+                    System.out.println("Saturday is no longer in the list"); 
+                }
+                for (DaysOfWeekEnum day : days) {
+                    System.out.println(day);
+                }
+
 	}
 }

core-java-networking/pom.xml

@@ -3,8 +3,8 @@
     <modelVersion>4.0.0</modelVersion>
     <artifactId>core-java-networking</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>core-java-networking</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

core-java-perf/README.md

@@ -6,3 +6,4 @@
 - [Understanding Memory Leaks in Java](https://www.baeldung.com/java-memory-leaks)
 - [OutOfMemoryError: GC Overhead Limit Exceeded](http://www.baeldung.com/java-gc-overhead-limit-exceeded)
 - [Basic Introduction to JMX](http://www.baeldung.com/java-management-extensions)
+- [Monitoring Java Applications with Flight Recorder](https://www.baeldung.com/java-flight-recorder-monitoring)

core-java-perf/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>core-java-perf</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>core-java-perf</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

core-java-security/README.md

@@ -9,3 +9,4 @@
 - [Hashing a Password in Java](https://www.baeldung.com/java-password-hashing)
 - [SSL Handshake Failures](https://www.baeldung.com/java-ssl-handshake-failures)
 - [SHA-256 Hashing in Java](https://www.baeldung.com/sha-256-hashing-java)
+- [Enabling TLS v1.2 in Java 7](https://www.baeldung.com/java-7-tls-v12)

core-java-security/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>core-java-security</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>core-java-security</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

core-java-sun/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>core-java-sun</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>core-java-sun</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

core-java/README.md

@@ -47,3 +47,7 @@
 - [Console I/O in Java](http://www.baeldung.com/java-console-input-output)
 - [Formatting with printf() in Java](https://www.baeldung.com/java-printstream-printf)
 - [Retrieve Fields from a Java Class Using Reflection](https://www.baeldung.com/java-reflection-class-fields)
+- [Introduction to Basic Syntax in Java](https://www.baeldung.com/java-syntax)
+- [Using Curl in Java](https://www.baeldung.com/java-curl)
+- [Finding Leap Years in Java](https://www.baeldung.com/java-leap-year)
+- [Java Bitwise Operators](https://www.baeldung.com/java-bitwise-operators)

core-java/src/main/java/com/baeldung/jar/JarExample.java

@@ -0,0 +1,9 @@
+package com.baeldung.jar;
+
+public class JarExample {
+
+    public static void main(String[] args) {
+        System.out.println("Hello Baeldung Reader!");
+    }
+
+}

core-java/src/main/java/com/baeldung/jar/example_manifest.txt

@@ -0,0 +1 @@
+Main-Class: com.baeldung.jar.JarExample

core-kotlin/README.md

@@ -51,3 +51,4 @@
 - [Operator Overloading in Kotlin](https://www.baeldung.com/kotlin-operator-overloading)
 - [Inline Classes in Kotlin](https://www.baeldung.com/kotlin-inline-classes)
 - [Creating Java static final Equivalents in Kotlin](https://www.baeldung.com/kotlin-java-static-final)
+- [Nested forEach in Kotlin](https://www.baeldung.com/kotlin-nested-foreach)

core-kotlin/pom.xml

@@ -64,13 +64,13 @@
         <dependency>
             <groupId>nl.komponents.kovenant</groupId>
             <artifactId>kovenant</artifactId>
-            <version>3.3.0</version>
+            <version>${kovenant.version}</version>
             <type>pom</type>
         </dependency>
         <dependency>
             <groupId>uy.kohesive.injekt</groupId>
             <artifactId>injekt-core</artifactId>
-            <version>1.16.1</version>
+            <version>${injekt-core.version}</version>
         </dependency>
     </dependencies>
 
@@ -82,6 +82,8 @@
         <assertj.version>3.10.0</assertj.version>
         <h2database.version>1.4.197</h2database.version>
         <fuel.version>1.15.0</fuel.version>
+		<kovenant.version>3.3.0</kovenant.version>
+		<injekt-core.version>1.16.1</injekt-core.version>
     </properties>
 
 </project>

core-kotlin/src/test/kotlin/com/baeldung/kotlin/junit5/CalculatorTest5.kt

@@ -7,12 +7,12 @@ class CalculatorTest5 {
     private val calculator = Calculator()
 
     @Test
-    fun whenAdding1and3_thenAnswerIs4() {
+    fun `Adding 1 and 3 should be equal to 4`() {
         Assertions.assertEquals(4, calculator.add(1, 3))
     }
 
     @Test
-    fun whenDividingBy0_thenErrorOccurs() {
+    fun `Dividing by zero should throw the DivideByZeroException`() {
         val exception = Assertions.assertThrows(DivideByZeroException::class.java) {
             calculator.divide(5, 0)
         }
@@ -21,7 +21,7 @@ class CalculatorTest5 {
     }
 
     @Test
-    fun whenSquaringNumbers_thenCorrectAnswerGiven() {
+    fun `The square of a number should be equal to that number multiplied in itself`() {
         Assertions.assertAll(
                 Executable { Assertions.assertEquals(1, calculator.square(1)) },
                 Executable { Assertions.assertEquals(4, calculator.square(2)) },
@@ -76,7 +76,7 @@ class CalculatorTest5 {
             Tag("logarithms")
     )
     @Test
-    fun whenIcalculateLog2Of8_thenIget3() {
+    fun `Log to base 2 of 8 should be equal to 3`() {
         Assertions.assertEquals(3.0, calculator.log(2, 8))
     }
 }

core-kotlin/src/test/kotlin/com/baeldung/kotlin/junit5/SimpleTest5.kt

@@ -5,15 +5,16 @@ import org.junit.jupiter.api.Disabled
 import org.junit.jupiter.api.Test
 
 class SimpleTest5 {
+
     @Test
-    fun whenEmptyList_thenListIsEmpty() {
+    fun `isEmpty should return true for empty lists`() {
         val list = listOf<String>()
         Assertions.assertTrue(list::isEmpty)
     }
 
     @Test
     @Disabled
-    fun when3equals4_thenTestFails() {
+    fun `3 is equal to 4`() {
         Assertions.assertEquals(3, 4) {
             "Three does not equal four"
         }

couchbase/pom.xml

@@ -5,9 +5,9 @@
     <groupId>com.baeldung</groupId>
     <artifactId>couchbase</artifactId>
     <version>0.1-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>couchbase</name>
     <description>Couchbase Tutorials</description>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

custom-pmd/pom.xml

@@ -4,8 +4,8 @@
     <groupId>org.baeldung.pmd</groupId>
     <artifactId>custom-pmd</artifactId>
     <version>0.0.1</version>
-    <packaging>jar</packaging>
     <name>custom-pmd</name>
+    <packaging>jar</packaging>
     <url>http://maven.apache.org</url>
 
     <dependencies>

ddd/pom.xml

@@ -1,6 +1,12 @@
 <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>
+    <groupId>com.baeldung.ddd</groupId>
+    <artifactId>ddd</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>ddd</name>
+    <packaging>jar</packaging>
+    <description>DDD series examples</description>
 
     <parent>
         <groupId>org.springframework.boot</groupId>
@@ -9,18 +15,6 @@
         <relativePath /> <!-- lookup parent from repository -->
     </parent>
 
-    <groupId>com.baeldung.ddd</groupId>
-    <artifactId>ddd</artifactId>
-    <version>0.0.1-SNAPSHOT</version>
-    <packaging>jar</packaging>
-    <name>ddd</name>
-    <description>DDD series examples</description>
-
-    <properties>
-        <joda-money.version>1.0.1</joda-money.version>
-        <maven-surefire-plugin.version>2.22.0</maven-surefire-plugin.version>
-    </properties>
-
     <dependencies>
         <dependency>
             <groupId>org.springframework.boot</groupId>
@@ -88,4 +82,10 @@
             <scope>test</scope>
         </dependency>
     </dependencies>
+
+    <properties>
+        <joda-money.version>1.0.1</joda-money.version>
+        <maven-surefire-plugin.version>2.22.0</maven-surefire-plugin.version>
+    </properties>
+	
 </project>

deeplearning4j/pom.xml

@@ -3,9 +3,9 @@
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.baeldung.deeplearning4j</groupId>
     <artifactId>deeplearning4j</artifactId>
-    <packaging>jar</packaging>
     <version>1.0-SNAPSHOT</version>
     <name>deeplearning4j</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

disruptor/pom.xml

@@ -4,8 +4,8 @@
     <groupId>com.baeldung</groupId>
     <artifactId>disruptor</artifactId>
     <version>0.1.0-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>disruptor</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

flyway-cdi-extension/pom.xml

@@ -8,44 +8,49 @@
     <version>1.0-SNAPSHOT</version>
     <name>flyway-cdi-extension</name>
 
-    <properties>
-        <maven.compiler.source>1.8</maven.compiler.source>
-        <maven.compiler.target>1.8</maven.compiler.target>
-    </properties>
-
     <dependencies>
         <dependency>
             <groupId>javax.enterprise</groupId>
             <artifactId>cdi-api</artifactId>
-            <version>2.0.SP1</version>
+            <version>${cdi-api.version}</version>
         </dependency>
         <dependency>
             <groupId>org.jboss.weld.se</groupId>
             <artifactId>weld-se-core</artifactId>
-            <version>3.0.5.Final</version>
+            <version>${weld-se-core.version}</version>
             <scope>runtime</scope>
         </dependency>
         <dependency>
             <groupId>org.flywaydb</groupId>
             <artifactId>flyway-core</artifactId>
-            <version>5.1.4</version>
+            <version>${flyway-core.version}</version>
         </dependency>
         <dependency>
             <groupId>org.apache.tomcat</groupId>
             <artifactId>tomcat-jdbc</artifactId>
-            <version>8.5.33</version>
+            <version>${tomcat-jdbc.version}</version>
         </dependency>
         <dependency>
             <groupId>javax.annotation</groupId>
             <artifactId>javax.annotation-api</artifactId>
-            <version>1.3.2</version>
+            <version>${javax.annotation-api.version}</version>
         </dependency>
         <dependency>
             <groupId>com.h2database</groupId>
             <artifactId>h2</artifactId>
-            <version>1.4.197</version>
+            <version>${h2.version}</version>
             <scope>runtime</scope>
         </dependency>
     </dependencies>
 
+    <properties>
+        <maven.compiler.source>1.8</maven.compiler.source>
+        <maven.compiler.target>1.8</maven.compiler.target>
+		<cdi-api.version>2.0.SP1</cdi-api.version>
+		<weld-se-core.version>3.0.5.Final</weld-se-core.version>
+		<flyway-core.version>5.1.4</flyway-core.version>
+		<tomcat-jdbc.version>8.5.33</tomcat-jdbc.version>
+		<javax.annotation-api.version>1.3.2</javax.annotation-api.version>
+		<h2.version>1.4.197</h2.version>
+    </properties>
 </project>

geotools/pom.xml

@@ -4,8 +4,8 @@
 	<modelVersion>4.0.0</modelVersion>
 	<artifactId>geotools</artifactId>
 	<version>0.0.1-SNAPSHOT</version>
-	<packaging>jar</packaging>
 	<name>geotools</name>
+	<packaging>jar</packaging>
 	<url>http://maven.apache.org</url>
 
 	<parent>

google-cloud/pom.xml

@@ -4,9 +4,9 @@
     <modelVersion>4.0.0</modelVersion>
     <artifactId>google-cloud</artifactId>
     <version>0.1-SNAPSHOT</version>
-    <packaging>jar</packaging>
     <name>google-cloud</name>
     <description>Google Cloud Tutorials</description>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>

google-web-toolkit/pom.xml

@@ -7,9 +7,9 @@
 	<modelVersion>4.0.0</modelVersion>
 	<groupId>com.baeldung</groupId>
 	<artifactId>google-web-toolkit</artifactId>
-	<packaging>war</packaging>
 	<version>1.0-SNAPSHOT</version>
 	<name>google-web-toolkit</name>
+	<packaging>war</packaging>
 	
     <parent>
         <groupId>com.baeldung</groupId>
@@ -23,7 +23,7 @@
 			<dependency>
 				<groupId>com.google.gwt</groupId>
 				<artifactId>gwt</artifactId>
-				<version>2.8.2</version>
+				<version>${gwt.version}</version>
 				<type>pom</type>
 				<scope>import</scope>
 			</dependency>
@@ -49,7 +49,7 @@
 		<dependency>
 			<groupId>junit</groupId>
 			<artifactId>junit</artifactId>
-			<version>4.11</version>
+			<version>${junit.version}</version>
 			<scope>test</scope>
 		</dependency>
 	</dependencies>
@@ -120,6 +120,8 @@
 		<!-- Don't let your Mac use a crazy non-standard encoding -->
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+		<junit.version>4.11</junit.version>
+		<gwt.version>2.8.2</gwt.version>
 	</properties>
 	
 </project>

grpc/pom.xml

@@ -3,8 +3,8 @@
     <modelVersion>4.0.0</modelVersion>
     <artifactId>grpc</artifactId>
     <version>0.0.1-SNAPSHOT</version>
-    <packaging>jar</packaging>
 	<name>grpc</name>
+    <packaging>jar</packaging>
 	
     <parent>
         <groupId>com.baeldung</groupId>

guice/pom.xml

@@ -1,13 +1,12 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<project xmlns="http://maven.apache.org/POM/4.0.0"
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	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>
     <groupId>com.baeldung.examples.guice</groupId>
     <artifactId>guice</artifactId>
     <version>1.0-SNAPSHOT</version>
-	<packaging>jar</packaging>
     <name>guice</name>
+    <packaging>jar</packaging>
 
     <parent>
         <groupId>com.baeldung</groupId>
@@ -21,25 +20,10 @@
             <artifactId>guice</artifactId>
             <version>${guice.version}</version>
         </dependency>
-
-		<dependency>
-			<groupId>org.springframework</groupId>
-			<artifactId>spring-context</artifactId>
-			<version>${spring.version}</version>
-		</dependency>
-
-		<dependency>
-			<groupId>org.springframework</groupId>
-			<artifactId>spring-test</artifactId>
-			<version>${springtest.version}</version>
-			<scope>test</scope>
-		</dependency>
     </dependencies>
 
     <properties>
-		<guice.version>4.2.2</guice.version>
+        <guice.version>4.1.0</guice.version>
-		<spring.version>5.1.3.RELEASE</spring.version>
-		<springtest.version>5.1.3.RELEASE</springtest.version>
     </properties>
 
 </project>