E.g I'd like to see how Integer Class is coded. Is that available?
When you install JDK
, there is an option to install the sources, which is selected by default.
After installing, when you open a project, IDEs will usually automatically index Java sources. If not, you can attach the sources to your project depending on your IDE.
Alternatively, you open <JDK_HOME>\src.zip
and see the Java sources.