Merge branch 'master' of https://github.com/eugenp/tutorials

core-java/src/test/java/com/baeldung/comparable/ComparableUnitTest.java

@@ -0,0 +1,29 @@
+package com.baeldung.comparable;
+
+import static org.junit.Assert.assertEquals;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import org.junit.Test;
+
+public class ComparableUnitTest {
+
+    @Test
+    public void whenUsingComparable_thenSortedList() {
+        List<Player> footballTeam = new ArrayList<Player>();
+        Player player1 = new Player(59, "John", 20);
+        Player player2 = new Player(67, "Roger", 22);
+        Player player3 = new Player(45, "Steven", 24);
+        footballTeam.add(player1);
+        footballTeam.add(player2);
+        footballTeam.add(player3);
+        Collections.sort(footballTeam);
+        assertEquals(footballTeam.get(0)
+            .getName(), "Steven");
+        assertEquals(footballTeam.get(2)
+            .getRanking(), 67);
+    }
+
+}

core-java/src/test/java/com/baeldung/comparator/ComparatorUnitTest.java

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+package com.baeldung.comparator;
+
+import static org.junit.Assert.assertEquals;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import org.junit.Before;
+import org.junit.Test;
+
+public class ComparatorUnitTest {
+
+    List<Player> footballTeam;
+
+    @Before
+    public void setUp() {
+        footballTeam = new ArrayList<Player>();
+        Player player1 = new Player(59, "John", 20);
+        Player player2 = new Player(67, "Roger", 22);
+        Player player3 = new Player(45, "Steven", 24);
+        footballTeam.add(player1);
+        footballTeam.add(player2);
+        footballTeam.add(player3);
+    }
+
+    @Test
+    public void whenUsingRankingComparator_thenSortedList() {
+        PlayerRankingComparator playerComparator = new PlayerRankingComparator();
+        Collections.sort(footballTeam, playerComparator);
+        assertEquals(footballTeam.get(0)
+            .getName(), "Steven");
+        assertEquals(footballTeam.get(2)
+            .getRanking(), 67);
+    }
+
+    @Test
+    public void whenUsingAgeComparator_thenSortedList() {
+        PlayerAgeComparator playerComparator = new PlayerAgeComparator();
+        Collections.sort(footballTeam, playerComparator);
+        assertEquals(footballTeam.get(0)
+            .getName(), "John");
+        assertEquals(footballTeam.get(2)
+            .getRanking(), 45);
+    }
+
+}

core-java/src/test/java/com/baeldung/comparator/Java8ComparatorUnitTest.java

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+package com.baeldung.comparator;
+
+import static org.junit.Assert.assertEquals;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
+
+import org.junit.Before;
+import org.junit.Test;
+
+public class Java8ComparatorUnitTest {
+
+    List<Player> footballTeam;
+
+    @Before
+    public void setUp() {
+        footballTeam = new ArrayList<Player>();
+        Player player1 = new Player(59, "John", 22);
+        Player player2 = new Player(67, "Roger", 20);
+        Player player3 = new Player(45, "Steven", 24);
+        footballTeam.add(player1);
+        footballTeam.add(player2);
+        footballTeam.add(player3);
+    }
+
+    @Test
+    public void whenComparing_UsingLambda_thenSorted() {
+        System.out.println("************** Java 8 Comaparator **************");
+        Comparator<Player> byRanking = (Player player1, Player player2) -> player1.getRanking() - player2.getRanking();
+
+        System.out.println("Before Sorting : " + footballTeam);
+        Collections.sort(footballTeam, byRanking);
+        System.out.println("After Sorting : " + footballTeam);
+        assertEquals(footballTeam.get(0)
+            .getName(), "Steven");
+        assertEquals(footballTeam.get(2)
+            .getRanking(), 67);
+    }
+
+    @Test
+    public void whenComparing_UsingComparatorComparing_thenSorted() {
+        System.out.println("********* Comaparator.comparing method *********");
+        System.out.println("********* byRanking *********");
+        Comparator<Player> byRanking = Comparator.comparing(Player::getRanking);
+
+        System.out.println("Before Sorting : " + footballTeam);
+        Collections.sort(footballTeam, byRanking);
+        System.out.println("After Sorting : " + footballTeam);
+        assertEquals(footballTeam.get(0)
+            .getName(), "Steven");
+        assertEquals(footballTeam.get(2)
+            .getRanking(), 67);
+        
+        System.out.println("********* byAge *********");
+        Comparator<Player> byAge = Comparator.comparing(Player::getAge);
+
+        System.out.println("Before Sorting : " + footballTeam);
+        Collections.sort(footballTeam, byAge);
+        System.out.println("After Sorting : " + footballTeam);
+        assertEquals(footballTeam.get(0)
+            .getName(), "Roger");
+        assertEquals(footballTeam.get(2)
+            .getRanking(), 45);
+    }
+
+}