I am having 4.3 years of experience Java/J2EE. I have worked with companies like Siemens,Polaris. I am not really interested in coding now .So i want to shift to testing.
I am also done SCJP and Oracle 9i SQL certification.
My entire experience in JAVA.
Start testing. You could write junit tests or ask if you could set up Selenium or even just offer to review/test the code of your teammates. This builds your skills and gives you test experience that you can use to transition to a more QA role.
Most companies have a dearth of people who *want* to do testing so it is easier than switching the other way. Also, someone who wants to test rather than got dumped into it has more enthusiasm and tends to be better at it.