@Nullable
  private PsiFile findAlternativeJreSourceFile(ClsClassImpl psiClass) {
    String sourceFileName = psiClass.getSourceFileName();
    String packageName = ((PsiClassOwner)psiClass.getContainingFile()).getPackageName();
    String relativePath = packageName.isEmpty() ? sourceFileName : packageName.replace('.', '/') + '/' + sourceFileName;
    Sdk alternativeJre = myDebugProcess.getSession().getAlternativeJre();

    if (alternativeJre != null) {
      for (VirtualFile file : AlternativeJreClassFinder.getSourceRoots(alternativeJre)) {
        VirtualFile source = file.findFileByRelativePath(relativePath);
        if (source != null && source.isValid()) {
          PsiFile psiSource = psiClass.getManager().findFile(source);
          if (psiSource instanceof PsiClassOwner) {
            return psiSource;
          }
        }
      }
    }
    return null;
  }
@Nullable
  private PsiFile findAlternativeJreSourceFile(ClsClassImpl psiClass)