Example Code for BAEL-1048 (#2316)

* added updated example codes

* updated example code StringToCharStream

* deleted StringToCharStream.java locally

* removed redundant file

* added code for apache commons collection SetUtils

* refactored example code

* added example code for bytebuddy

* added example code for PCollections

* update pom

libraries/pom.xml

@@ -448,6 +448,11 @@
             <artifactId>byte-buddy-agent</artifactId>
             <version>${bytebuddy.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.pcollections</groupId>
+            <artifactId>pcollections</artifactId>
+            <version>${pcollections.version}</version>
+        </dependency>
     </dependencies>
     <properties>
         <multiverse.version>0.7.0</multiverse.version>
@@ -487,5 +492,6 @@
         <org.hamcrest.java-hamcrest.version>2.0.0.0</org.hamcrest.java-hamcrest.version>
         <hll.version>1.6.0</hll.version>
         <bytebuddy.version>1.7.1</bytebuddy.version>
+        <pcollections.version>2.1.2</pcollections.version>
     </properties>
 </project>

libraries/src/test/java/com/baeldung/pcollections/PCollectionsUnitTest.java

@@ -0,0 +1,91 @@
+package com.baeldung.pcollections;
+
+import org.junit.Test;
+import org.pcollections.*;
+
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.Map;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+public class PCollectionsUnitTest {
+
+    @Test
+    public void whenEmpty_thenCreateEmptyHashPMap() {
+        HashPMap<String, String> pmap = HashTreePMap.empty();
+        assertEquals(pmap.size(), 0);
+    }
+
+    @Test
+    public void givenKeyValue_whenSingleton_thenCreateNonEmptyHashPMap() {
+        HashPMap<String, String> pmap1 = HashTreePMap.singleton("key1", "value1");
+        assertEquals(pmap1.size(), 1);
+    }
+
+    @Test
+    public void givenExistingHashMap_whenFrom_thenCreateHashPMap() {
+        Map map = new HashMap();
+        map.put("mkey1", "mval1");
+        map.put("mkey2", "mval2");
+
+        HashPMap<String, String> pmap2 = HashTreePMap.from(map);
+        assertEquals(pmap2.size(), 2);
+    }
+
+    @Test
+    public void whenHashPMapMethods_thenPerformOperations() {
+
+        HashPMap<String, String> pmap = HashTreePMap.empty();
+        pmap = pmap.plus("key1", "value1");
+        assertEquals(pmap.size(), 1);
+
+        Map map = new HashMap();
+        map.put("key2", "val2");
+        map.put("key3", "val3");
+        pmap = pmap.plusAll(map);
+
+        assertEquals(pmap.size(), 3);
+
+        pmap = pmap.minus("key1");
+        assertFalse(pmap.containsKey("key1"));
+
+        pmap = pmap.minusAll(map.keySet());
+        assertEquals(pmap.size(), 0);
+
+    }
+
+    @Test
+    public void whenTreePVectorMethods_thenPerformOperations() {
+        TreePVector pVector = TreePVector.empty();
+
+        pVector = pVector.plus("e1");
+        pVector = pVector.plusAll(Arrays.asList("e2", "e3", "e4"));
+        assertEquals(4, pVector.size());
+
+        TreePVector pSub = pVector.subList(0, 2);
+        assertTrue(pSub.contains("e1") && pSub.contains("e2"));
+
+        TreePVector pVW = (TreePVector) pVector.with(0, "e10");
+        assertEquals(pVW.get(0), "e10");
+
+        pVector = pVector.minus("e1");
+        TreePVector pV1 = pVector.minusAll(Arrays.asList("e2", "e3"));
+        assertEquals(pV1.size(), 1);
+    }
+
+    @Test
+    public void whenMapPSetMethods_thenPerformOperations() {
+
+        MapPSet pSet = HashTreePSet.empty()
+                .plusAll(Arrays.asList("e1","e2","e3","e4"));
+        assertEquals(pSet.size(), 4);
+
+        pSet = pSet.minus("e4");
+        assertFalse(pSet.contains("e4"));
+
+    }
+
+}