static class CompilerBot {
  static bool verbose;

  static File compileSnippet(S snippetID) {
    ret compileSnippet(snippetID, "");
  }
  
  // returns jar path
  static File compileSnippet(S snippetID, S javaTarget) {
    S transpiledSrc = getServerTranspiled2(snippetID);
    int i = transpiledSrc.indexOf('\n');
    String libs = transpiledSrc.substring(0, Math.max(0, i));
    if (verbose)
      print("Compiling snippet: " + snippetID + ". Libs: " + libs);
    transpiledSrc = transpiledSrc.substring(i+1);
    return compile(transpiledSrc, libs, javaTarget);
  }

  static File compile(S src) {
    ret compile(src, "");
  }
  
  static File compile(S src, S libs) {
    ret compile(src, libs, null);
  }

  static File compile(S src, S dehlibs, S javaTarget) {
    if (verbose)
      print("Compiling " + l(src) + " chars");
    S md5 = md5(dehlibs + "\n" + src);
    File jar = getJarFile(md5);
    if (jar == null || jar.length() <= 22) {
      // have to compile
      
      javaCompileToJar_standard(src, dehlibs, jar);
    } else {
      if (verbose)
        print("Getting classes from cache (" + jar.getAbsolutePath() + ", " + jar.length() + " bytes)");
      touchFile(jar); // so we can find the unused ones easier
    }
    
    ret jar;
  }

  static File getJarFile(S md5) {
    assertTrue(isMD5(md5));
    ret new File(getCacheProgramDir("#1002203"), md5 + ".jar");
  }
}