cufy.concurrent

Class Lock<T>

java.lang.Object

java.lang.Thread

cufy.concurrent.Lock<T>

Type Parameters:

T - the type of that lock

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, java.lang.Runnable

public class Lock<T>
extends java.lang.Thread
implements java.io.Closeable

A java lock locker thread. Designed to be a replacement of wrapping the code with 'synchronized' statement. By creating a thread on the background to lock() that lock and hold it until unlock() get invoked.

Since:

07-Dec-2019

Version:

0.1.3

Author:

lsafer

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

java.lang.Thread.State, java.lang.Thread.UncaughtExceptionHandler

Field Summary

Fields

Modifier and Type	Field and Description
protected static int	CLOSE The lock holder should end it's thread.
protected T	lock The targeted lock.
protected static int	LOCK The lock holder should gain it's targeted lock.
protected java.lang.Thread	master The thread that have created this.
protected java.util.concurrent.atomic.AtomicInteger	state The reference to communicate with the lock holder thread.
protected static int	UNLOCK The lock holder should release it's targeted lock.

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

Constructors

Constructor and Description
Lock() Initialise a new lock.
Lock(T lock) Initialize a new lock holder.

Method Summary

Modifier and Type	Method and Description
private void	assertMasterThread() Assert that the caller thread is the master of this lock.
private void	assertThisThread() Assert that the caller thread is this lock.
void	close() Closes this stream and releases any system resources associated with it.
protected void	close0() Do code before closing the lock.
void	lock() Hold the lock.
protected void	lock0() Sleep with while owning the lock.
void	run() If this thread was constructed using a separate Runnable run object, then that Runnable object's run method is called; otherwise, this method does nothing and returns.
void	unlock() Release the targeted lock by this.
protected void	unlock0() Sleep until notified.

Methods inherited from class java.lang.Thread

activeCount, checkAccess, clone, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

CLOSE

protected static final int CLOSE

The lock holder should end it's thread.

See Also:

Constant Field Values

LOCK

protected static final int LOCK

The lock holder should gain it's targeted lock.

See Also:

Constant Field Values

UNLOCK

protected static final int UNLOCK

The lock holder should release it's targeted lock.

See Also:

Constant Field Values

lock

protected final T lock

The targeted lock.

master

protected final java.lang.Thread master

The thread that have created this. To avoid serving other threads.

state

protected final java.util.concurrent.atomic.AtomicInteger state

The reference to communicate with the lock holder thread. Representing the state integer code.

Constructor Detail

Lock

public Lock(T lock)

Initialize a new lock holder.

Parameters:

lock - the targeted lock

Throws:

java.lang.NullPointerException - if the given lock is null

Lock

public Lock()

Initialise a new lock. Locking on itself.

Method Detail

close

public void close()

Closes this stream and releases any system resources associated with it. If the stream is already closed then invoking this method has no effect.

As noted in AutoCloseable.close(), cases where the close may fail require careful attention. It is strongly advised to relinquish the underlying resources and to internally mark the Closeable as closed, prior to throwing the IOException.

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

Throws:

IllegalThreadException - if the caller thread isn't the owner thread of this lock

run

public void run()

If this thread was constructed using a separate Runnable run object, then that Runnable object's run method is called; otherwise, this method does nothing and returns.

Subclasses of Thread should override this method.

Specified by:

run in interface java.lang.Runnable

Overrides:

run in class java.lang.Thread

Throws:

IllegalThreadException - if the caller thread is not this

See Also:

Thread.start(), Thread.stop(), Thread.Thread(ThreadGroup, Runnable, String)

lock

public void lock()

Hold the lock. Wait for the lock been gained.

Throws:

java.lang.IllegalThreadStateException - if this lock already closed

IllegalThreadException - if the caller thread isn't the master of this

unlock

public void unlock()

Release the targeted lock by this.

Throws:

IllegalThreadException - if the caller thread isn't the master of this

close0

protected void close0()

Do code before closing the lock.

Throws:

IllegalThreadException - if the caller thread isn't this thread

lock0

protected void lock0()

Sleep with while owning the lock.

Throws:

IllegalThreadException - if the caller thread isn't this thread

unlock0

protected void unlock0()

Sleep until notified.

Throws:

IllegalThreadException - if the caller thread isn't this thread

assertMasterThread

private void assertMasterThread()

Assert that the caller thread is the master of this lock.

Throws:

IllegalThreadException - if the caller thread isn't the master of this

assertThisThread

private void assertThisThread()

Assert that the caller thread is this lock.

Throws:

IllegalThreadException - if the caller thread isn't this thread