Delete JoinerSplitter.java (#1161)

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

@@ -1,40 +0,0 @@
-package com.baeldung.streamApi;
-
-import java.util.Arrays;
-import java.util.List;
-import java.util.stream.Collectors;
-import java.util.stream.Stream;
-
-public class JoinerSplitter {
-
-    public static String join(String[] arrayOfString) {
-        return Arrays
-          .asList(arrayOfString)
-          .stream()
-          .map(x -> x)
-          .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());
-    }
-
-}