我需要列出在java.lang.ApplicationShutdownHooks上注册的钩子
2022-09-03 13:58:42
我有一个第三方应用程序,它有一个错误,导致它在只需要1个时注册多个关闭钩子。
我的问题是,我如何查看已注册的关机钩子是什么?我想迭代它们,然后调用 remove 方法。保存钩子的集合是私有静态的,不包含访问器。我们已经尝试过反射,但是由于该类是包私有的,因此我们必须使我们的破解程序成为java.lang的一部分,这是一个被禁止的包。
有什么想法吗?
/*
* %W% %E%
*
* Copyright (c) 2004, Oracle and/or its affiliates. All rights reserved.
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
class ApplicationShutdownHooks {
static {
Shutdown.add(1 /* shutdown hook invocation order */,
new Runnable() {
public void run() {
runHooks();
}
});
}
/* The set of registered hooks */
private static IdentityHashMap<Thread, Thread> hooks = new IdentityHashMap<Thread, Thread>();
private void ApplicationShutdownHooks() {}
/* Add a new shutdown hook. Checks the shutdown state and the hook itself,
* but does not do any security checks.
*/
static synchronized void add(Thread hook) {
if(hooks == null)
throw new IllegalStateException("Shutdown in progress");
if (hook.isAlive())
throw new IllegalArgumentException("Hook already running");
if (hooks.containsKey(hook))
throw new IllegalArgumentException("Hook previously registered");
hooks.put(hook, hook);
}
/* Remove a previously-registered hook. Like the add method, this method
* does not do any security checks.
*/
static synchronized boolean remove(Thread hook) {
if(hooks == null)
throw new IllegalStateException("Shutdown in progress");
if (hook == null)
throw new NullPointerException();
return hooks.remove(hook) != null;
}
/* Iterates over all application hooks creating a new thread for each
* to run in. Hooks are run concurrently and this method waits for
* them to finish.
*/
static void runHooks() {
Collection<Thread> threads;
synchronized(ApplicationShutdownHooks.class) {
threads = hooks.keySet();
hooks = null;
}
for (Thread hook : threads) {
hook.start();
}
for (Thread hook : threads) {
try {
hook.join();
} catch (InterruptedException x) { }
}
}
}