Java getPid()

Ever since I started programming in Java it has bugged me that I can't get the process id of the Java VM. Well today I was browsing the OpenJPA code and found this gem:

private static String getPid() {
    // This relies on the undocumented convention of the 
    // RuntimeMXBean's name starting with the PID, but 
    // there appears to be no other way to obtain the 
    // current process' id, which we need for the attach 
    // process
    RuntimeMXBean bean = ManagementFactory.getRuntimeMXBean();
    String pid = bean.getName();
    if (pid.indexOf("@") != -1) {
        pid = pid.substring(0, pid.indexOf("@"));
    }
    return pid;
}