BAEL-718 Quick intro to javatuplesMaster (#1389)

* yasin.bhojawala@gmail.com

Evaluation article on Different Types of Bean Injection in Spring

* Revert "yasin.bhojawala@gmail.com"

This reverts commit 963cc51a7a15b75b550108fe4e198cd65a274032.

* Fixing compilation error and removing unused import

* Introduction to Java9 StackWalking API - yasin.bhojawala@gmail.com

Code examples for the article "Introduction to Java9 StackWalking API"

* BAEL-608 Introduction to Java9 StackWalking API

* BAEL-608 Introduction to Java9 StackWalking API

changing the test names to BDD style

* BAEL-608 Introduction to Java9 StackWalking API

correcting the typo

* BAEL-608 Introduction to Java9 StackWalking API

improving method names

* BAEL-608 Introduction to Java9 StackWalking API

test method names improvements

* BAEL-718 Quick intro to javatuples

libraries/README.md

@@ -0,0 +1,5 @@
+The libraries module contains examples related to small libraries that are relatively easy to use and does not require any separate module of its own.
+
+The code examples related to different libraries should go in a new package.
+
+Remember, for advanced libraries like JUnit, Jackson, etc. we already have separate modules. Please make sure to have a look at the existing modules in such cases.

libraries/pom.xml

@@ -1,6 +1,5 @@
 <?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">
 	<parent>
 		<artifactId>parent-modules</artifactId>
@@ -47,7 +46,17 @@
 			<artifactId>jasypt</artifactId>
 			<version>${jasypt.version}</version>
 		</dependency>
-
+		<dependency>
+			<groupId>org.javatuples</groupId>
+			<artifactId>javatuples</artifactId>
+			<version>${javatuples.version}</version>
+		</dependency>
+		<!-- https://mvnrepository.com/artifact/org.assertj/assertj-core -->
+		<dependency>
+			<groupId>org.assertj</groupId>
+			<artifactId>assertj-core</artifactId>
+			<version>${assertj.version}</version>
+		</dependency>
 	</dependencies>
 
 	<properties>
@@ -55,6 +64,8 @@
 		<commons-lang.version>3.5</commons-lang.version>
 		<junit.version>4.12</junit.version>
 		<jasypt.version>1.9.2</jasypt.version>
+		<javatuples.version>1.2</javatuples.version>
+		<assertj.version>3.6.2</assertj.version>
 	</properties>
 
 </project>

libraries/src/test/java/com/baeldung/javatuples/JavaTuplesTest.java

@@ -0,0 +1,118 @@
+package com.baeldung.javatuples;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.Arrays;
+import java.util.List;
+
+import org.javatuples.KeyValue;
+import org.javatuples.LabelValue;
+import org.javatuples.Pair;
+import org.javatuples.Quartet;
+import org.javatuples.Triplet;
+import org.javatuples.Unit;
+import org.junit.Test;
+
+public class JavaTuplesTest {
+
+    @SuppressWarnings("unused")
+    @Test
+    public void whenCreatingTuples_thenCreateTuples() {
+        Pair<String, Integer> pair = new Pair<String, Integer>("This is a pair", 55);
+        Triplet<String, Integer, Double> triplet = Triplet.with("hello", 23, 33.2);
+
+        List<String> collectionOfNames = Arrays.asList("john", "doe", "anne", "alex");
+        Quartet<String, String, String, String> quartet = Quartet.fromCollection(collectionOfNames);
+
+        Pair<String, String> pairFromList = Pair.fromIterable(collectionOfNames, 2);
+
+        String[] names = new String[] { "john", "doe", "anne" };
+        Triplet<String, String, String> triplet2 = Triplet.fromArray(names);
+    }
+
+    @Test
+    public void whenGetValuexFromTuples_thenRetriveValueWithType() {
+        Quartet<String, Double, Integer, String> quartet = Quartet.with("john", 72.5, 32, "1051 SW");
+
+        String name = quartet.getValue0();
+        Integer age = quartet.getValue2();
+        assertThat(name).isEqualTo("john");
+        assertThat(age).isEqualTo(32);
+    }
+
+    @Test
+    public void whenGetKeyValue_thenGetKeyValue() {
+        KeyValue<Integer, String> keyValue = KeyValue.with(5, "F");
+        Integer key = keyValue.getKey();
+        String value = keyValue.getValue();
+
+        assertThat(key).isEqualTo(5);
+        assertThat(value).isEqualTo("F");
+    }
+
+    @Test
+    public void whenGetLabelValue_thenGetLabelValue() {
+        LabelValue<Integer, String> labelValue = LabelValue.with(5, "F");
+        Integer key = labelValue.getLabel();
+        String value = labelValue.getValue();
+
+        assertThat(key).isEqualTo(5);
+        assertThat(value).isEqualTo("F");
+    }
+
+    @Test
+    public void whenGetValueFromTuples_thenRetriveValueWithoutType() {
+        Quartet<String, Double, Integer, String> quartet = Quartet.with("john", 72.5, 32, "1051 SW");
+
+        String name = (String) quartet.getValue(0);
+        Integer age = (Integer) quartet.getValue(2);
+        assertThat(name).isEqualTo("john");
+        assertThat(age).isEqualTo(32);
+    }
+
+    @Test
+    public void whenSetValueInTuple_thenGetANewTuple() {
+        Pair<String, Integer> john = Pair.with("john", 32);
+        Pair<String, Integer> alex = john.setAt0("alex");
+        assertThat(john.toString()).isNotEqualTo(alex.toString());
+    }
+
+    @Test
+    public void whenAddNewElement_thenCreateNewTuple() {
+        Pair<String, Integer> pair1 = Pair.with("john", 32);
+        Triplet<String, Integer, String> triplet1 = pair1.add("1051 SW");
+        assertThat(triplet1.contains("john"));
+        assertThat(triplet1.contains(32));
+        assertThat(triplet1.contains("1051 SW"));
+
+        Pair<String, Integer> pair2 = Pair.with("alex", 45);
+        Quartet<String, Integer, String, Integer> quartet2 = pair1.add(pair2);
+        assertThat(quartet2.containsAll(pair1));
+        assertThat(quartet2.containsAll(pair2));
+
+        Quartet<String, Integer, String, Integer> quartet1 = pair1.add("alex", 45);
+        assertThat(quartet1.containsAll("alex", "john", 32, 45));
+
+        Triplet<String, String, Integer> triplet2 = pair1.addAt1("1051 SW");
+        assertThat(triplet2.indexOf("john")).isEqualTo(0);
+        assertThat(triplet2.indexOf("1051 SW")).isEqualTo(1);
+        assertThat(triplet2.indexOf(32)).isEqualTo(2);
+
+        Unit<Integer> unit = pair1.removeFrom0();
+        assertThat(unit.contains(32));
+    }
+
+    @Test
+    public void whenCallingToList_thenReturnList() {
+        Quartet<String, Double, Integer, String> quartet = Quartet.with("john", 72.5, 32, "1051 SW");
+        List<Object> list = quartet.toList();
+        assertThat(list.size()).isEqualTo(4);
+    }
+
+    @Test
+    public void whenCallingToArray_thenReturnArray() {
+        Quartet<String, Double, Integer, String> quartet = Quartet.with("john", 72.5, 32, "1051 SW");
+        Object[] array = quartet.toArray();
+        assertThat(array.length).isEqualTo(4);
+    }
+}