/*
     * Load JPLIS agent which will load the agent JAR file and invoke
     * the agentmain method.
     */

    public void loadAgent(String agent, String options)
        throws AgentLoadException, AgentInitializationException, IOException
    {

  {- -------------------------------------------
  (1) (変数宣言など)
      ---------------------------------------- -}

            String args = agent;
            if (options != null) {
                args = args + "=" + options;
            }

  {- -------------------------------------------
  (1) "instrument" (libinstrumentの意) を引数にして 
      sun.tools.attach.HotSpotVirtualMachine.loadAgentLibrary(String agentLibrary, String options) を呼び出す.

      (なお, 失敗した場合は適切な例外をスローする)
      ---------------------------------------- -}

            try {
                loadAgentLibrary("instrument", args);
            } catch (AgentLoadException x) {
                throw new InternalError("instrument library is missing in target VM");
            } catch (AgentInitializationException x) {
                /*
                 * Translate interesting errors into the right exception and
                 * message (FIXME: create a better interface to the instrument
                 * implementation so this isn't necessary)
                 */
                int rc = x.returnValue();
                switch (rc) {
                    case JNI_ENOMEM:
                        throw new AgentLoadException("Insuffient memory");
                    case ATTACH_ERROR_BADJAR:
                        throw new AgentLoadException("Agent JAR not found or no Agent-Class attribute");
                    case ATTACH_ERROR_NOTONCP:
                        throw new AgentLoadException("Unable to add JAR file to system class path");
                    case ATTACH_ERROR_STARTFAIL:
                        throw new AgentInitializationException("Agent JAR loaded but agent failed to initialize");
                    default :
                        throw new AgentLoadException("Failed to load agent - unknown reason: " + rc);
                }
            }
        }