diff --git a/.circleci/config.yml b/.circleci/config.yml
new file mode 100644
index 00000000..8ea8ffe4
--- /dev/null
+++ b/.circleci/config.yml
@@ -0,0 +1,36 @@
+# Use the latest 2.1 version of CircleCI pipeline process engine.
+# See: https://circleci.com/docs/2.0/configuration-reference
+version: 2.1
+
+# Define a job to be invoked later in a workflow.
+# See: https://circleci.com/docs/2.0/configuration-reference/#jobs
+jobs:
+  # Below is the definition of your job to build and test your app, you can rename and customize it as you want.
+  build-and-test:
+    # These next lines define a Docker executor: https://circleci.com/docs/2.0/executor-types/
+    # You can specify an image from Dockerhub or use one of our Convenience Images from CircleCI's Developer Hub.
+    # Be sure to update the Docker image tag below to openjdk version of your application.
+    # A list of available CircleCI Docker Convenience Images are available here: https://circleci.com/developer/images/image/cimg/openjdk
+    docker:
+      - image: cimg/openjdk:11.0
+    # Add steps to the job
+    # See: https://circleci.com/docs/2.0/configuration-reference/#steps
+    steps:
+      # Checkout the code as the first step.
+      - checkout
+      # Use mvn clean and package as the standard maven build phase
+      - run:
+          name: Build
+          command: mvn -B -DskipTests clean package
+      # Then run your tests!
+      - run:
+          name: Test
+          command: mvn test
+
+# Invoke jobs via workflows
+# See: https://circleci.com/docs/2.0/configuration-reference/#workflows
+workflows:
+  sample: # This is the name of the workflow, feel free to change it to better match your workflow.
+    # Inside the workflow, you define the jobs you want to run.
+    jobs:
+      - build-and-test
diff --git a/src/main/java/travis_ci_tutorial_java/SimpleCalculator.java b/src/main/java/travis_ci_tutorial_java/SimpleCalculator.java
index a768b9a2..5c76a652 100755
--- a/src/main/java/travis_ci_tutorial_java/SimpleCalculator.java
+++ b/src/main/java/travis_ci_tutorial_java/SimpleCalculator.java
@@ -4,4 +4,14 @@ public class SimpleCalculator {
 	public int add(int a, int b) {
 		return a + b;
 	}
+	public int sub(int a, int b){ 
+		return a - b; 
+	}
+	public int multi(int a, int b){ 
+		return a * b; 
+	}	
+	public int divide(int a, int b){ 
+		return a / b; 
+	}
 }
+
diff --git a/src/test/java/travis_ci_tutorial_java/SimpleCalculatorTest.java b/src/test/java/travis_ci_tutorial_java/SimpleCalculatorTest.java
index 9c578eb9..adb17a62 100755
--- a/src/test/java/travis_ci_tutorial_java/SimpleCalculatorTest.java
+++ b/src/test/java/travis_ci_tutorial_java/SimpleCalculatorTest.java
@@ -11,4 +11,8 @@ public void testAdd() {
 		SimpleCalculator calc = new SimpleCalculator();
 		assertEquals(calc.add(1, 1), 2);
 	}
+	public void testsub() { 
+		SimpleCalculator calc = new SimpleCalculator();
+		assertEquals(calc.sub(1, 1), 0);
+	}
 }
diff --git a/target/classes/travis_ci_tutorial_java/SimpleCalculator.class b/target/classes/travis_ci_tutorial_java/SimpleCalculator.class
index aadae118..df19cdde 100644
Binary files a/target/classes/travis_ci_tutorial_java/SimpleCalculator.class and b/target/classes/travis_ci_tutorial_java/SimpleCalculator.class differ
diff --git a/target/test-classes/travis_ci_tutorial_java/SimpleCalculatorTest.class b/target/test-classes/travis_ci_tutorial_java/SimpleCalculatorTest.class
index f6880b57..9534b6b4 100644
Binary files a/target/test-classes/travis_ci_tutorial_java/SimpleCalculatorTest.class and b/target/test-classes/travis_ci_tutorial_java/SimpleCalculatorTest.class differ