Eclipse, open declaration that is defined in a library

Question

In Eclipse if I press F3 or open declaration on a reference that is in one of my libraries, it opens a read only copy of the code.

I thought this quite useful at first a

Answer 1

If you have the dependent library open as a Java project within Eclipse, you can add the project to the build path. ( Right click on project -> properties -> java build path -> Projects -> Add).

Under the Order and Export section, make sure the project is above the library.

After doing this when you press F3, the .java file will open.