java獲取系統進程號

public static final int jvmPid() {
		try {
			RuntimeMXBean runtime = ManagementFactory.getRuntimeMXBean();
			Field jvm = runtime.getClass().getDeclaredField("jvm");
			jvm.setAccessible(true);
			VMManagement mgmt = (VMManagement) jvm.get(runtime);
			Method pidMethod = mgmt.getClass().getDeclaredMethod("getProcessId");
			pidMethod.setAccessible(true);
			int pid = (Integer) pidMethod.invoke(mgmt);
			return pid;
		} catch (Exception e) {
			return -1;
		}
	}