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| /**/
private static final ConcurrentHashMap<String, Long> LOCK_DTO_MAP = new ConcurrentHashMap<>();
private static final ConcurrentHashMap<String, Semaphore> SEMAPHORE_MAP =
new ConcurrentHashMap<>();
private static final long TIMEOUT_DURATION = 60_000; // 60 seconds
public static boolean lock(String key) {
Semaphore semaphore = SEMAPHORE_MAP.computeIfAbsent(key, k -> new Semaphore(1, true));
boolean acquired = false;
try {
// 1. 拿到许可证
acquired = semaphore.tryAcquire(1, TimeUnit.SECONDS);
Preconditions.checkState(acquired, "获取锁超时: " + key);
// 2. 现在互斥了，再操作被保护资源
Long old = LOCK_DTO_MAP.putIfAbsent(key, System.currentTimeMillis());
Preconditions.checkState(old == null, "Lock already held by this thread for key: " + key);
return true;
} catch (Exception ignored) {
} finally {
/* 4. 关键：只有真正拿到过许可的线程才需要“善后” */
if (acquired) {
/* 4.1 判断是否超时，超时就当“没发生过”直接删记录 */
try {
long holdTime = System.currentTimeMillis() - LOCK_DTO_MAP.get(key);
if (holdTime > TIMEOUT_DURATION) {
LOCK_DTO_MAP.remove(key); // 删记录" 超时，记录+许可证已清理"
}
} finally {
semaphore.release(); // 还许可证
}
}
}
return false;
}
/** 清空StripedLockUtils的所有数据 */
public static void clearAppRestart() {
for (String key : LOCK_DTO_MAP.keySet()) {
StreamUtils.silentException(
() -> {
unlock(key);
SEMAPHORE_MAP.remove(key);
});
}
}
public static void unlock(String key) {
StreamUtils.silentException(() -> LOCK_DTO_MAP.remove(key));
}
|