Merge pull request #17608 from yabetancourt/BAEL-8298-Java-8-Stream-anyMatch()-vs.-findAny()

BAEL-8298 Java 8 Stream anyMatch() vs. findAny()

Author: davidmartinezbarua

core-java-modules/core-java-streams-6/src/test/java/com/baeldung/streams/findanyvsanymatch/FindAnyAnyMatchUnitTest.java

@@ -0,0 +1,83 @@
+package com.baeldung.streams.findanyvsanymatch;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.Arrays;
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class FindAnyAnyMatchUnitTest {
+
+    @Test
+    public void whenFilterStreamUsingFindAny_thenOK() {
+        List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+
+        Integer result = numbers.stream()
+          .filter(n -> n % 2 == 0)
+          .findAny()
+          .orElse(null);
+
+        assertNotNull(result);
+        assertTrue(Arrays.asList(2, 4, 6, 8, 10).contains(result));
+    }
+
+    @Test
+    public void whenParallelStreamUsingFindAny_thenOK() {
+        List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+
+        Integer result = numbers.parallelStream()
+          .filter(n -> n % 2 == 0)
+          .findAny()
+          .orElse(null);
+
+        assertNotNull(result);
+        assertTrue(Arrays.asList(2, 4, 6, 8, 10).contains(result));
+    }
+
+
+    @Test
+    public void whenFilterStreamUsingAnyMatch_thenOK() {
+        List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+
+        boolean result = numbers.parallelStream()
+          .anyMatch(n -> n % 2 == 0);
+
+        assertTrue(result);
+    }
+
+    @Test
+    public void whenFilterStreamUsingFindFirst_thenOK() {
+        List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+
+        Integer result = numbers.stream()
+          .filter(n -> n % 2 == 0)
+          .findFirst()
+          .orElse(null);
+
+        assertNotNull(result);
+        assertEquals(2, result);
+    }
+
+    @Test
+    public void whenCountingElementsInStream_thenOK() {
+        List<Integer> numbers = Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+
+        long count = numbers.stream()
+          .filter(n -> n % 2 == 0)
+          .count();
+
+        assertEquals(5, count);
+    }
+
+    @Test
+    public void whenCheckingAllMatch_thenOK() {
+        List<Integer> numbers = Arrays.asList(2, 4, 6, 8, 10);
+
+        boolean allEven = numbers.stream()
+          .allMatch(n -> n % 2 == 0);
+
+        assertTrue(allEven);
+    }
+
+}