BAEL-998:- Java Vavr interoperability

vavr/src/test/java/com/baeldung/vavr/interoperability/CollectionsInteroperabilityUnitTest.java

@@ -0,0 +1,91 @@
+package com.baeldung.vavr.interoperability;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import java.util.Arrays;
+import java.util.Optional;
+
+import org.junit.Test;
+
+import io.vavr.collection.HashMap;
+import io.vavr.collection.LinkedHashSet;
+import io.vavr.collection.List;
+import io.vavr.collection.Map;
+import io.vavr.collection.Stream;
+
+public class CollectionsInteroperabilityUnitTest {
+
+  @Test
+  public void givenParams_whenVavrList_thenReturnJavaList() {
+    List<String> vavrStringList = List.of("JAVA", "Javascript", "Scala");
+
+    java.util.List<String> javaStringList = vavrStringList.toJavaList();
+    assertTrue(javaStringList instanceof java.util.List);
+  }
+
+  @Test
+  public void givenParams_whenVavrStream_thenReturnJavaStream() {
+    Stream<String> vavrStream = Stream.of("JAVA", "Javascript", "Scala");
+
+    java.util.stream.Stream<String> javaParallelStream = vavrStream.toJavaParallelStream();
+    assertTrue(javaParallelStream instanceof java.util.stream.Stream);
+
+    java.util.List<String> javaStringList = vavrStream.toJavaList();
+    assertTrue(javaStringList instanceof java.util.List);
+  }
+
+  @Test
+  public void givenParams_whenVavrMap_thenReturnJavaMap() {
+    Map<String, String> vavrMap = HashMap.of("1", "a", "2", "b", "3", "c");
+
+    java.util.Map<String, String> javaMap = vavrMap.toJavaMap();
+    assertTrue(javaMap instanceof java.util.Map);
+  }
+
+  @Test
+  public void givenParams_whenJavaList_thenReturnVavrListUsingOfAll() {
+    java.util.List<String> javaList = Arrays.asList("Java", "Haskell", "Scala");
+    List<String> vavrList = List.ofAll(javaList);
+    assertTrue(vavrList instanceof io.vavr.collection.List);
+  }
+
+  @Test
+  public void givenParams_whenJavaStream_thenReturnVavrListUsingOfAll() {
+    java.util.stream.Stream<String> javaStream = Arrays.asList("Java", "Haskell", "Scala")
+      .stream();
+    Stream<String> vavrStream = Stream.ofAll(javaStream);
+    assertTrue(vavrStream instanceof io.vavr.collection.Stream);
+  }
+
+  @Test(expected = UnsupportedOperationException.class)
+  public void givenParams_whenVavrListConverted_thenException() {
+    java.util.List<String> javaList = List.of("Java", "Haskell", "Scala")
+      .asJava();
+    javaList.add("Python");
+    assertEquals(4, javaList.size());
+  }
+
+  @Test
+  public void givenParams_whenVavrListConvertedToMutable_thenRetunMutableList() {
+    java.util.List<String> javaList = List.of("Java", "Haskell", "Scala")
+      .asJavaMutable();
+    javaList.add("Python");
+    assertEquals(4, javaList.size());
+  }
+
+  @Test
+  public void givenParams_WhenVavarListConvertedToLinkedSet_thenReturnLinkedSet() {
+    List<String> vavrList = List.of("Java", "Haskell", "Scala", "Java");
+    LinkedHashSet<String> linkedSet = (LinkedHashSet<String>) vavrList.toLinkedSet();
+    assertEquals(3, linkedSet.size());
+  }
+
+  @Test
+  public void givenParams_WhenVavrList_thenReturnJavaOptional() {
+    List<String> vavrList = List.of("Java");
+    Optional<String> optional = vavrList.toJavaOptional();
+    assertEquals("Java", optional.get());
+  }
+
+}