Java Pass By Value and Pass By Reference.

April 29th, 2008

Pass by value in java means passing a copy of the value to be passed. Pass by reference in java means the passing the address itself. In Java the arguments are always passed by value. Java only supports pass by value.

With Java objects, the object reference itself is passed by value and so both the original reference and parameter copy both refer to the same Java object. Java primitives too are passed by value.

Next: Can an unreachable Java object become reachable again?

Java is strictly ‘Pass By Value’

Abhishek Khandelwal on November 3rd, 2009 9:30 pm

For Java newbies, this explanation on java pass by reference can be confusing. It would be
better to explain by example. The reason is because with Java
primitives, the results are different than with objects.

The problem comes in because, for primitives, the value of the
argument can be altered (in the method), but it doesn’t affect the
source variable. With an object reference being passed, that
object can be operated on (in the method) and its values changed.

Big difference.

mjt on December 17th, 2009 9:52 am

very good explanation on pass by value and pass by reference in java. thanks.

shiv on March 22nd, 2010 9:29 am

If the callee function can change the object’s values passed, then it should be called as pass by reference right?

Manoj on June 8th, 2010 6:19 pm

Yes Manoj. You are exactly right. If the passed object’s state can be changed so that it gets reflected in the caller method then it is called pass by reference. Java doesn’t has pass by reference. It is strictly pass by value.

Joe on June 8th, 2010 7:03 pm

Hi Moderator/Owner could you please explain a bit more, the answers here sounds confusing.

Thanks

Vishal on June 15th, 2010 11:04 pm

Got the answer here..
CHeck this out.

http://www.javaworld.com/javaworld/javaqa/2000-05/03-qa-0526-pass.html

Vishal on June 15th, 2010 11:07 pm

I WANTS TO KNOW THE OOPS CONCEPTS IN JAVA

RAGASUTHA on June 24th, 2010 6:28 am

Explanation between pass by value and java pass by reference is confusing. can you give a sample java source code?

Priya on July 16th, 2010 6:56 pm

java does not support pointers, thus anything is always passed by value.

jeRrRKKKK on July 20th, 2010 1:21 pm

Yes There is pass by reference in java..
Reference are passed by value to the function is nothing but pass by reference…. but the primitives are always passed by value

Anonymous on July 26th, 2010 5:14 am

@Anonymous – everything in java is pass by value. NOTHING is pass by reference in java. Even the references are passed by value only.

Kindly read the whole article. Its simple and small!!

Joe on July 26th, 2010 5:42 pm