Add documentation to NonReentrantLock
This commit is contained in:
parent
580c6069fa
commit
f1c375109e
@ -20,48 +20,97 @@ import java.util.concurrent.locks.AbstractQueuedSynchronizer;
|
||||
import java.util.concurrent.locks.Condition;
|
||||
import java.util.concurrent.locks.Lock;
|
||||
|
||||
/**
|
||||
* A custom implementation of a lock that does not allow reentry
|
||||
*/
|
||||
public final class NonReentrantLock extends AbstractQueuedSynchronizer
|
||||
implements Lock {
|
||||
|
||||
/**
|
||||
* The serial version unique ID
|
||||
*/
|
||||
private static final long serialVersionUID = -833780837233068610L;
|
||||
|
||||
/**
|
||||
* The {@link Thread} that owns this {@link NonReentrantLock}
|
||||
*/
|
||||
private Thread owner;
|
||||
|
||||
/**
|
||||
* Locks this {@link NonReentrantLock}
|
||||
*/
|
||||
@Override
|
||||
public void lock() {
|
||||
acquire(1);
|
||||
}
|
||||
|
||||
/**
|
||||
* Locks this {@link NonReentrantLock}, but allow interruption
|
||||
*
|
||||
* @throws InterruptedException The lock was interrupted
|
||||
*/
|
||||
@Override
|
||||
public void lockInterruptibly() throws InterruptedException {
|
||||
acquireInterruptibly(1);
|
||||
}
|
||||
|
||||
/**
|
||||
* Try to lock this {@link NonReentrantLock}
|
||||
*
|
||||
* @return True if locking was successful, otherwise false
|
||||
*/
|
||||
@Override
|
||||
public boolean tryLock() {
|
||||
return tryAcquire(1);
|
||||
}
|
||||
|
||||
/**
|
||||
* Tries to lock this {@link NonReentrantLock} over a period of time
|
||||
*
|
||||
* @param time The maximum number of time units to attempt to get a lock for.
|
||||
* @param unit The {@link TimeUnit} associated with the time parameter
|
||||
* @return True if the lock was successful, otherwise false
|
||||
* @throws InterruptedException The locking attempt was interrupted
|
||||
*/
|
||||
@Override
|
||||
public boolean tryLock(long time, TimeUnit unit)
|
||||
throws InterruptedException {
|
||||
return tryAcquireNanos(1, unit.toNanos(time));
|
||||
}
|
||||
|
||||
/**
|
||||
* Unlocks this {@link NonReentrantLock}
|
||||
*/
|
||||
@Override
|
||||
public void unlock() {
|
||||
release(1);
|
||||
}
|
||||
|
||||
/**
|
||||
* Checks to see if this {@link NonReentrantLock} is held by the current {@link Thread}
|
||||
*
|
||||
* @return True if held by the current thread, otherwise false
|
||||
*/
|
||||
public boolean isHeldByCurrentThread() {
|
||||
return isHeldExclusively();
|
||||
}
|
||||
|
||||
/**
|
||||
* Creates a new {@link Condition}
|
||||
*
|
||||
* @return The condition object
|
||||
*/
|
||||
@Override
|
||||
public Condition newCondition() {
|
||||
return new ConditionObject();
|
||||
}
|
||||
|
||||
/**
|
||||
* Try to acquire a lock
|
||||
*
|
||||
* @param acquires A number that is sent by acquiring methods
|
||||
* @return True if a lock is acquired, otherwise false
|
||||
*/
|
||||
@Override
|
||||
protected boolean tryAcquire(int acquires) {
|
||||
if (compareAndSetState(0, 1)) {
|
||||
@ -71,6 +120,12 @@ public final class NonReentrantLock extends AbstractQueuedSynchronizer
|
||||
return false;
|
||||
}
|
||||
|
||||
/**
|
||||
* Tries to release the lock
|
||||
*
|
||||
* @param releases A number that is passed by the release methods
|
||||
* @return True if a release is granted, otherwise false
|
||||
*/
|
||||
@Override
|
||||
protected boolean tryRelease(int releases) {
|
||||
if (Thread.currentThread() != owner) {
|
||||
@ -81,6 +136,11 @@ public final class NonReentrantLock extends AbstractQueuedSynchronizer
|
||||
return true;
|
||||
}
|
||||
|
||||
/**
|
||||
* Checks to see if this {@link NonReentrantLock} is held exclusively by the current {@link Thread}
|
||||
*
|
||||
* @return True if held exclusively, otherwise false
|
||||
*/
|
||||
@Override
|
||||
protected boolean isHeldExclusively() {
|
||||
return getState() != 0 && owner == Thread.currentThread();
|
||||
|
Loading…
Reference in New Issue
Block a user