diff --git a/.gitignore b/.gitignore
index a8f09b4135..08f570ad06 100644
--- a/.gitignore
+++ b/.gitignore
@@ -41,4 +41,5 @@ SpringDataInjectionDemo/.mvn/wrapper/maven-wrapper.properties
 spring-call-getters-using-reflection/.mvn/wrapper/maven-wrapper.properties
 
 spring-check-if-a-property-is-null/.mvn/wrapper/maven-wrapper.properties
-/vertx-and-rxjava/.vertx/
+*.springBeans
+
diff --git a/core-java/pom.xml b/core-java/pom.xml
index d4d249934b..0e57b35ab8 100644
--- a/core-java/pom.xml
+++ b/core-java/pom.xml
@@ -372,6 +372,31 @@
                     </arguments>
                 </configuration>
             </plugin>
+          
+            <plugin>
+				        <groupId>org.codehaus.mojo</groupId>
+				        <artifactId>exec-maven-plugin</artifactId>
+				        
+                <executions>
+					          <execution>
+						            <id>run-benchmarks</id>
+						            <phase>integration-test</phase>
+						            <goals>
+							              <goal>exec</goal>
+						            </goals>
+						            <configuration>
+							              <classpathScope>test</classpathScope>
+							              <executable>java</executable>
+							              <arguments>
+								                <argument>-classpath</argument>
+								                <classpath />
+								                <argument>org.openjdk.jmh.Main</argument>
+								                <argument>.*</argument>
+							              </arguments>
+						            </configuration>
+					          </execution>
+				        </executions>
+            </plugin>
         </plugins>
 
     </build>
@@ -448,4 +473,4 @@
         <maven-compiler-plugin.version>3.6.0</maven-compiler-plugin.version>
         <maven-surefire-plugin.version>2.19.1</maven-surefire-plugin.version>
     </properties>
-</project>
+</project>
\ No newline at end of file
diff --git a/core-java/src/main/java/com/baeldung/string/StringBufferStringBuilder.java b/core-java/src/main/java/com/baeldung/string/StringBufferStringBuilder.java
new file mode 100644
index 0000000000..74f489d57f
--- /dev/null
+++ b/core-java/src/main/java/com/baeldung/string/StringBufferStringBuilder.java
@@ -0,0 +1,46 @@
+package com.baeldung.string;
+
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.Scope;
+import org.openjdk.jmh.annotations.State;
+import org.openjdk.jmh.runner.Runner;
+import org.openjdk.jmh.runner.RunnerException;
+import org.openjdk.jmh.runner.options.Options;
+import org.openjdk.jmh.runner.options.OptionsBuilder;
+
+public class StringBufferStringBuilder {
+
+    public static void main(String[] args) throws RunnerException {
+
+        Options opt = new OptionsBuilder()
+            .include(StringBufferStringBuilder.class.getSimpleName())
+            .build();
+
+        new Runner(opt).run();
+    }
+    
+    @State(Scope.Benchmark)
+    public static class MyState {
+        int iterations = 1000;
+        String initial = "abc";
+        String suffix = "def";
+    }
+     
+    @Benchmark
+    public StringBuffer benchmarkStringBuffer(MyState state) {
+        StringBuffer stringBuffer = new StringBuffer(state.initial);
+        for (int i = 0; i < state.iterations; i++) {
+            stringBuffer.append(state.suffix);
+        }
+        return stringBuffer;
+    }
+
+    @Benchmark
+    public StringBuilder benchmarkStringBuilder(MyState state) {
+        StringBuilder stringBuilder = new StringBuilder(state.initial);
+        for (int i = 0; i < state.iterations; i++) {
+            stringBuilder.append(state.suffix);
+        }
+        return stringBuilder;
+    }
+}
\ No newline at end of file
diff --git a/core-java/src/test/java/com/baeldung/maths/RoundTest.java b/core-java/src/test/java/com/baeldung/maths/RoundTest.java
index 9e3c049c96..5ce9523e21 100644
--- a/core-java/src/test/java/com/baeldung/maths/RoundTest.java
+++ b/core-java/src/test/java/com/baeldung/maths/RoundTest.java
@@ -15,56 +15,56 @@ public class RoundTest {
     private double expected = 2.03d;
 
     @Test
-    public void givenDecimalNumber_whenRoundToNDecimalPlaces_thenGetExpectedResult() {
+    public void givenDecimalNumber_whenRoundToNDecimalPlaces_thenGetExpectedResult() {   
         Assert.assertEquals(expected, Round.round(value, places), delta);
         Assert.assertEquals(expected, Round.roundNotPrecise(value, places), delta);
         Assert.assertEquals(expected, Round.roundAvoid(value, places), delta);
         Assert.assertEquals(expected, Precision.round(value, places), delta);
         Assert.assertEquals(expected, DoubleRounder.round(value, places), delta);
-
+        
         places = 3;
         expected = 2.035d;
-
+        
         Assert.assertEquals(expected, Round.round(value, places), delta);
         Assert.assertEquals(expected, Round.roundNotPrecise(value, places), delta);
         Assert.assertEquals(expected, Round.roundAvoid(value, places), delta);
         Assert.assertEquals(expected, Precision.round(value, places), delta);
         Assert.assertEquals(expected, DoubleRounder.round(value, places), delta);
-
+        
         value = 1000.0d;
         places = 17;
         expected = 1000.0d;
-
+        
         Assert.assertEquals(expected, Round.round(value, places), delta);
         Assert.assertEquals(expected, Round.roundNotPrecise(value, places), delta);
         Assert.assertNotEquals(expected, Round.roundAvoid(value, places), delta); // Returns: 92.23372036854776 !
         Assert.assertEquals(expected, Precision.round(value, places), delta);
         Assert.assertEquals(expected, DoubleRounder.round(value, places), delta);
-
+        
         value = 256.025d;
         places = 2;
         expected = 256.03d;
-
+        
         Assert.assertEquals(expected, Round.round(value, places), delta);
         Assert.assertNotEquals(expected, Round.roundNotPrecise(value, places), delta); // Returns: 256.02 !
         Assert.assertNotEquals(expected, Round.roundAvoid(value, places), delta); // Returns: 256.02 !
         Assert.assertEquals(expected, Precision.round(value, places), delta);
         Assert.assertNotEquals(expected, DoubleRounder.round(value, places), delta); // Returns: 256.02 !
-
-        value = 260.775d;
+        
+        value = 260.775d; 
         places = 2;
         expected = 260.78d;
-
+        
         Assert.assertEquals(expected, Round.round(value, places), delta);
         Assert.assertNotEquals(expected, Round.roundNotPrecise(value, places), delta); // Returns: 260.77 !
         Assert.assertNotEquals(expected, Round.roundAvoid(value, places), delta); // Returns: 260.77 !
         Assert.assertEquals(expected, Precision.round(value, places), delta);
         Assert.assertNotEquals(expected, DoubleRounder.round(value, places), delta); // Returns: 260.77 !
-
+        
         value = 90080070060.1d;
         places = 9;
         expected = 90080070060.1d;
-
+        
         Assert.assertEquals(expected, Round.round(value, places), delta);
         Assert.assertEquals(expected, Round.roundNotPrecise(value, places), delta);
         Assert.assertNotEquals(expected, Round.roundAvoid(value, places), delta); // Returns: 9.223372036854776E9 !