Concurrency Gotchas 2
Whole series of bugs associated with synchronized issues.
synchronized(null) { // NPE
synchronized(obj) {
obj = new MyObject(); // Undermined synchronization
}
private static final String LOCK = "LOCK";
synchronized(LOCK) { // Interned strings use the same lock elsewhere
private static final Integer LOCK = 0;
synchronized(LOCK) // Same as string issue
// ReentrantLock FAIL
final Lock lock = new ReentrantLock()
synchronized(lock) {
Should be:
final Lock lock = new RentrantLock()
lock.lock()
try {
} finally {
lock.unlock()
}
You should lock on the variable being protected, or an explicit lock object (new Object())
