Lightweight processes (LWPs) bridge the user level and the kernel level. Each process contains one or more LWP, each of which runs one or more user threads. (See Figure 1-1.) The creation of a thread usually involves just the creation of some user context, but not the creation of an LWP.

The LWP appears to be a virtual processor on which the application can schedule a user thread to run, to the user-thread library. Each Light Weight Process is attached to a kernel thread, and it is kernel threads that the operating system schedules to run on physical processors.

4. Q: Statically associating only a single thread with a lightweight process is not such a good idea. Why not? A: Such an association effectively reduces to having only kernel-level threads, implying that much of the performance gain of having threads in the first place, is lost.

When a Java program starts up, one thread begins running immediately. This is usually called the main thread of our program, because it is the one that is executed when our program begins. Properties : It is the thread from which other “child” threads will be spawned.

When an application component starts and the application does not have any other components running, the Android system starts a new Linux process for the application with a single thread of execution. By default, all components of the same application run in the same process and thread (called the “main” thread).

Thread class provides the join() method which allows one thread to wait until another thread completes its execution. If t is a Thread object whose thread is currently executing, then t. join() will make sure that t is terminated before the next instruction is executed by the program.

Overriding of Thread class start() method Whenever we override start() method then our start() method will be executed just like a normal method call and new thread wont be created. We can override start/run method of Thread class because it is not final.

sleep() Method: Method Whenever Thread. sleep() functions to execute, it always pauses the current thread execution. If any other thread interrupts when the thread is sleeping, then InterruptedException will be thrown.

Comparison of yield(), join() and sleep() in Java

Yield means currently executing thread gives chance to the threads that have equal priority in the Thread-pool. Yield does not guarantee that it will change the state of the currently executing thread to runnable state immediately….Difference between Yield and Join Method in Java with Example.

Sleep() causes the currently executing thread to sleep (temporarily cease execution). Yield() causes the currently executing thread object to temporarily pause and allow other threads to execute.

A yield() method is a static method of Thread class and it can stop the currently executing thread and will give a chance to other waiting threads of the same priority. If in case there are no waiting threads or if all the waiting threads have low priority then the same thread will continue its execution.

Thread Class Methods

So since the only thread worth calling yield on is the current thread, they make the method static so you won’t waste time trying to call yield on some other thread. This is because whenever you are calling these methods, those are applied on the same thread that is running.

wait() causes current thread to wait until another thread invokes the notify() method or the notifyAll() method for this object. The thread then waits until it can re-obtain ownership of the monitor and resumes execution. This method should only be called by a thread that is the owner of this object’s monitor.

The major difference is that wait() releases the lock or monitor while sleep() doesn’t releases the lock or monitor while waiting. wait() is used for inter-thread communication while sleep() is used to introduce pause on execution, generally. Thread.

It tells the calling thread (a.k.a Current Thread) to wait until another thread invoke’s the notify() or notifyAll() method for this object, The thread waits until it reobtains the ownership of the monitor and Resume’s Execution….Related Articles.