public static IPackageFragmentRoot addRTJar13(IJavaProject jproject) throws CoreException { IPath[] rtJarPath = findRtJar(RT_STUBS_13); Map options = jproject.getOptions(false); JavaProjectHelper.set13CompilerOptions(options); jproject.setOptions(options); return addLibrary(jproject, rtJarPath[0], rtJarPath[1], rtJarPath[2]); }