Problem with joints

[SergioPadilla]

Hello,
I'm trying to use this physics layout, but I have found a problem when, in the main activity, I create a joint between two bodies. The joint is created correctly, but it's remove again, I think it is because in the 'onLayout' the world is recreated once and once again and only the bodies are safe for the next world. To try fix it, I modify the 'createWorld' method in the Physics class, but when I save the Joints in the array like bodies, I get an error with the memory, concretly this:
java.lang.OutOfMemoryError: Failed to allocate a 154589920 byte allocation with 33554432 free bytes and 125MB until OOM

Can help me? Thanks in advance.
Are the joints really removed? or, maybe, Am I doing something wrong?