BAEL-3207 Convert Char Array to String (#7692)

* BAEL-320 Convert Char Array to String

* BAEL-3207 re-formatting

java-strings-3/src/test/java/com/baeldung/string/charArrayToString/CharArrayToStringConversionUnitTest.java

@@ -0,0 +1,73 @@
+package com.baeldung.string.charArrayToString;
+
+import static org.hamcrest.Matchers.is;
+import static org.junit.Assert.assertThat;
+
+import com.google.common.base.Joiner;
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+public class CharArrayToStringConversionUnitTest {
+
+    @Test
+    public void whenStringConstructor_thenOK() {
+        final char[] charArray = { 'b', 'a', 'e', 'l', 'd', 'u', 'n', 'g' };
+
+        String string = new String(charArray);
+
+        assertThat(string, is("baeldung"));
+    }
+
+    @Test
+    public void whenStringCopyValueOf_thenOK() {
+        final char[] charArray = { 'b', 'a', 'e', 'l', 'd', 'u', 'n', 'g' };
+
+        String string = String.copyValueOf(charArray);
+
+        assertThat(string, is("baeldung"));
+    }
+
+    @Test
+    public void whenStringValueOf_thenOK() {
+        final char[] charArray = { 'b', 'a', 'e', 'l', 'd', 'u', 'n', 'g' };
+
+        String string = String.valueOf(charArray);
+
+        assertThat(string, is("baeldung"));
+    }
+
+    @Test
+    public void whenStringBuilder_thenOK() {
+        final char[] charArray = { 'b', 'a', 'e', 'l', 'd', 'u', 'n', 'g' };
+
+        StringBuilder sb = new StringBuilder();
+        for (char value : charArray) {
+            sb.append(value);
+        }
+
+        assertThat(sb.toString(), is("baeldung"));
+    }
+
+    @Test
+    public void whenStreamCollectors_thenOK() {
+        final Character[] charArray = { 'b', 'a', 'e', 'l', 'd', 'u', 'n', 'g' };
+
+        Stream<Character> charStream = Arrays.stream(charArray);
+        String string = charStream.map(String::valueOf).collect(Collectors.joining());
+
+        assertThat(string, is("baeldung"));
+    }
+
+    @Test
+    public void whenGoogleCommonBaseJoiners_thenOK() {
+        final Character[] charArray = { 'b', 'a', 'e', 'l', 'd', 'u', 'n', 'g' };
+
+        String string = Joiner.on("").join(charArray);
+
+        assertThat(string, is("baeldung"));
+    }
+
+}