BAEL-7105 Add code for StringBuilder comparison

core-java-modules/core-java-string-apis-2/pom.xml

@@ -33,6 +33,16 @@
 
     <build>
         <finalName>core-java-string-apis-2</finalName>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>11</source>
+                    <target>11</target>
+                </configuration>
+            </plugin>
+        </plugins>
         <resources>
             <resource>
                 <directory>src/main/resources</directory>

core-java-modules/core-java-string-apis-2/src/main/java/stringbuildercomparison/StringBuilderCompare.java

@@ -0,0 +1,17 @@
+package stringbuildercomparison;
+
+public class StringBuilderCompare {
+
+    public static boolean compare(StringBuilder one, StringBuilder two){
+        if(one.length() != two.length()){
+            return false;
+        }
+        for(int i = 0; i < one.length(); i++){
+            if(one.charAt(i) != two.charAt(i)){
+                return false;
+            }
+        }
+        return true;
+    }
+
+}

core-java-modules/core-java-string-apis-2/src/test/java/com/baeldung/stringbuildercomparison/StringBuilderComparisonUnitTest.java

@@ -0,0 +1,43 @@
+package com.baeldung.stringbuildercomparison;
+
+import static junit.framework.TestCase.assertEquals;
+import static junit.framework.TestCase.assertNotSame;
+
+import org.junit.Test;
+
+import stringbuildercomparison.StringBuilderCompare;
+
+public class StringBuilderComparisonUnitTest {
+
+    @Test
+    public void whenUsingJavaEight_givenTwoIdenticalStringBuilders_thenCorrectlyMatch(){
+        StringBuilder one = new StringBuilder("Hello");
+        StringBuilder two = new StringBuilder("Hello");
+        boolean result = StringBuilderCompare.compare(one, two);
+        assertEquals(true, result);
+    }
+
+    @Test
+    public void whenUsingJavaEight_givenTwoDifferentStringBuilders_thenCorrectlyIdentifyDifference(){
+        StringBuilder one = new StringBuilder("Hello");
+        StringBuilder two = new StringBuilder("World");
+        boolean result = StringBuilderCompare.compare(one, two);
+        assertEquals(false, result);
+    }
+
+    @Test
+    public void whenUsingJavaEleven_givenTwoIdenticalStringBuilders_thenCorrectlyMatch(){
+        StringBuilder one = new StringBuilder("Hello");
+        StringBuilder two = new StringBuilder("Hello");
+        assertEquals(0, one.compareTo(two));
+    }
+
+    @Test
+    public void whenUsingJavaEleven_givenTwoDifferentStringBuilders_thenCorrectlyIdentifyDifference(){
+        StringBuilder one = new StringBuilder("Hello");
+        StringBuilder two = new StringBuilder("World");
+        assertNotSame(0, one.compareTo(two));
+    }
+
+
+}