adding more functionality in split/join, added chars() usage (#1155)

* rest with spark java

* 4

* Update Application.java

* indentation changes

* spring @requestmapping shortcuts

* removing spring requestmapping and pushing spring-mvc-java

* Joining/Splitting Strings with Java and Stream API

* adding more join/split functionality

core-java/src/main/java/com/baeldung/streamApi/JoinerSplitter.java

@@ -14,10 +14,23 @@ public class JoinerSplitter {
 				.collect(Collectors.joining(","));
 	}
 	
+	public static String joinWithPrefixPostFix ( String[] arrayOfString ) {
+		return Arrays.asList(arrayOfString)
+				.stream()
+				.map(x -> x)
+				.collect(Collectors.joining(",","[","]"));
+	}
+	
 	public static List<String> split ( String str ) {
 		return Stream.of(str.split(","))
 				.map (elem -> new String(elem))
 				.collect(Collectors.toList());
 	}
 	
+	public static List<Character> splitToListOfChar ( String str ) {
+		return str.chars()
+				.mapToObj(item -> (char) item)
+				.collect(Collectors.toList());
+	}
+		
 }

core-java/src/test/java/com/baeldung/stream/JoinerSplitterTest.java

@@ -13,7 +13,9 @@ public class JoinerSplitterTest {
 
 	@Test
 	public void provided_array_convert_to_stream_and_convert_to_string() {
+
 		String[] programming_languages = {"java", "python", "nodejs", "ruby"};
+
 		String expectation = "java,python,nodejs,ruby";
 		
 		String result  = JoinerSplitter.join(programming_languages);
@@ -21,7 +23,17 @@ public class JoinerSplitterTest {
 	}
 	
 	@Test
-	public void provided_list_convert_to_stream_and_convert_to_list() {
+	public void provided_array_convert_to_stream_and_convert_to_prefixPostfixString() {
+		String[] programming_languages = {"java", "python", 
+				"nodejs", "ruby"};
+		String expectation = "[java,python,nodejs,ruby]";
+		
+		String result  = JoinerSplitter.joinWithPrefixPostFix(programming_languages);
+		assertEquals(result, expectation);
+	}
+	
+	@Test
+	public void provided_string_convert_to_stream_and_convert_to_listOfString() {
 		String programming_languages = "java,python,nodejs,ruby";
 		
 		List<String> expectation = new ArrayList<String>();
@@ -34,5 +46,20 @@ public class JoinerSplitterTest {
 		
 		assertEquals(result, expectation);
 	}
-	
+  
+	@Test
+	public void provided_string_convert_to_stream_and_convert_to_listOfChar() {
+		String programming_languages = "java,python,nodejs,ruby";
+		
+		List<Character> expectation = new ArrayList<Character>();
+		char[] charArray = programming_languages.toCharArray();
+		for (char c : charArray) {
+			expectation.add(c);
+		}
+		
+		List<Character> result  = JoinerSplitter.splitToListOfChar(programming_languages);
+		assertEquals(result, expectation);
+		
+	}
+  
 }