At first you can convert your project to Ant or Maven.
Link: how to convert a existing code into maven?
Once your code is convered to Maven, you can download and setup Jenkins.
Once your Jenkins setup is ready, you can go to http://localhost:8080 on your webbrowser to access the Jenkins dashboard.
Configure Jenkins:
1.Go to Manage Jenkins->Configure System
2.Configure JDK
-Give the JDK name
-JAVA_HOME : C:\Program Files\Java\jdk1.7.0_45
3.Maven configuration
-Give a maven name
-MAVEN_HOME : C:\apache-maven-3.2.5\apache-maven-3.2.5-bin\apache-maven-3.2.5
4.Global Maven_OPTS
âXmx512m
âXX:MaxPermSize=128m
5.Save once done
In Jenkins you can create new Job -> Select Maven project, enter project name -> click Ok
On the Job configuration page, enter SCM details and click on "SAVE" button.
Hope that helps!