Oracle Java SE JRE中的本机类位于何处？

Question

I was studying the java standard library classes and realized that some methods used the keyword native like in the code below:

     
    public class FileOutputStream extends OutputStream{

    private native void open0(String name, boolean append)
        throws FileNotFoundException;
}

I´ve already searched and found out that it is related to JNI API and it has to call a method in a non-java class file. However, I´m not finding this file. Where is it located in this case? Tks

Answer 1

A native method doesn't delegate to a "method", but a native function , which doesn't reside in any kind of class file. Rather it's in a platform-specific dynamic-link library. To find the C/C++ source code of a given native method in the JDK, you must clone the Mercurial repository of the OpenJDK and spend some time getting a bearing inside the vastness of that codebase. I recommend using find + grep a lot.

PS Oracle SE is not identical to OpenJDK, but they share 99% of the codebase. Also, since the Oracle-specific delta is closed-source, this is certainly your best (if not the only) bet.