Differences between Process and Thread

Q

What is the difference between Process and Thread?

✍: FYIcenter

A

A process can contain multiple threads. In most multithreading operating systems, a process gets its own memory address space; a thread doesn't. Threads typically share the heap belonging to their parent process.

For instance, a JVM runs in a single process in the host O/S. Threads in the JVM share the heap belonging to that process; that's why several threads may access the same object.

Typically, even though they share a common heap, threads have their own stack space. This is how one thread's invocation of a method is kept separate from another's.

This is all a gross over simplification, but it's accurate enough at a high level. Lots of details differ between operating systems.

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Invoking run() Method of a Thread
What invokes a thread's run() method? After a thread is started, via its start() method of the Thread class, the JVM invokes the thread's run() method when the thread is initially executed. 2007-03-03, 6248👍, 0💬

sleep() and yield() Methods
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Modifiers on Inner Classes
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Protected Methods
If a method is declared as protected, where may the method be accessed? A protected method may only be accessed by classes or interfaces of the same package or by subclasses of the class in which it is declared. 2007-03-03, 4883👍, 0💬

Acquiring a Lock on an Object
What happens when a thread cannot acquire a lock on an object? If a thread attempts to execute a synchronized method or synchronized statement and is unable to acquire an object's lock, it enters the waiting state until the lock becomes available. 2007-03-03, 4798👍, 0💬

NullPointerException on String Objects
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Inner Class Declared inside a Method
Can an inner class declared inside of a method access local variables of this method? It's possible if these variables are final. 2007-03-03, 4723👍, 0💬

Differences between Process and Thread
What is the difference between Process and Thread? A process can contain multiple threads. In most multithreading operating systems, a process gets its own memory address space; a thread doesn't. Threads typically share the heap belonging to their parent process. For instance, a JVM runs in a single... 2007-03-03, 4681👍, 0💬

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