Java Multithreading
Life Cycle of a Thread
New − A new thread begins its life cycle in the new state. It remains in this state until the program starts the thread. It is also referred to as a born thread.
Runnable − After a newly born thread is started, the thread becomes runnable. A thread in this state is considered to be executing its task.
Waiting − Sometimes, a thread transitions to the waiting state while the thread waits for another thread to perform a task. A thread transitions back to the runnable state only when another thread signals the waiting thread to continue executing.
Timed Waiting − A runnable thread can enter the timed waiting state for a specified interval of time. A thread in this state transitions back to the runnable state when that time interval expires or when the event it is waiting for occurs.
Terminated (Dead) − A runnable thread enters the terminated state when it completes its task or otherwise terminates.
Thread Methods
| Sr.No. | Method | Description |
|---|---|---|
| 1 | public void start() | Starts the thread in a separate path of execution, then invokes the run() method on this Thread object. |
| 2 | public void run() | If this Thread object was instantiated using a separate Runnable target, the run() method is invoked on that Runnable object. |
| 3 | public final void setName(String name) | Changes the name of the Thread object. There is also a getName() method for retrieving the name. |
| 4 | public final void setPriority(int priority) | Sets the priority of this Thread object. The possible values are between 1 and 10. |
| 5 | public final void setDaemon(boolean on) | A parameter of true denotes this Thread as a daemon thread. |
| 6 | public final void join(long millisec) | The current thread invokes this method on a second thread, causing the current thread to block until the second thread terminates or the specified number of milliseconds passes. |
| 7 | public void interrupt() | Interrupts this thread, causing it to continue execution if it was blocked for any reason. |
| 8 | public final boolean isAlive() | Returns true if the thread is alive, which is any time after the thread has been started but before it runs to completion. |
| Sr.No. | Method | Description |
|---|---|---|
| 1 | public static void yield() | Causes the currently running thread to yield to any other threads of the same priority that are waiting to be scheduled. |
| 2 | public static void sleep(long millisec) | Causes the currently running thread to block for at least the specified number of milliseconds. |
| 3 | public static boolean holdsLock(Object x) | Returns true if the current thread holds the lock on the given Object. |
| 4 | public static Thread currentThread() | Returns a reference to the currently running thread, which is the thread that invokes this method. |
| 5 | public static void dumpStack() | Prints the stack trace for the currently running thread, which is useful when debugging a multithreaded application. |
| Sr.No. | Method | Description |
|---|---|---|
| 1 | public void wait() | Causes the current thread to wait until another thread invokes the notify(). |
| 2 | public void notify() | Wakes up a single thread that is waiting on this object's monitor. |
| 3 | public void notifyAll() | Wakes up all the threads that called wait() on the same object. |
| 4 | public void suspend() | This method puts a thread in the suspended state and can be resumed using resume() method. |
| 5 | public void stop() | This method stops a thread completely. |
| 6 | public void resume() | This method resumes a thread, which was suspended using suspend() method. |
Examples
package:
com.tutorialspointInterthreadCommunication,TestThread,TestThreadSolution,CallableThreadTest,TestThreadByRunnable,TestThreadByThread,ThreadClassDemo,ThreadSynchronization,ThreadWithoutSynchronization