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.

2007-03-03, 5270👍, 0💬

wait(), notify() and notifyAll() Methods
What is the purpose of the wait(), notify(), and notifyAll() methods? The wait(),notify(), and notifyAll() methods are used to provide an efficient way for threads to communicate each other. 2007-03-03, 7117👍, 0💬

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, 7060👍, 0💬

sleep() and yield() Methods
What is the difference between yielding and sleeping? When a thread invokes its yield() method, it returns to the ready state. When a thread invokes its sleep() method, it returns to the waiting state. 2007-03-03, 6143👍, 0💬

Modifiers on Inner Classes
What modifiers may be used with an inner class that is a member of an outer class? A inner class may be declared as public, protected, private, static, final, or abstract. 2007-03-03, 5721👍, 0💬

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, 5612👍, 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, 5467👍, 0💬

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, 5364👍, 0💬

NullPointerException on String Objects
What can go wrong if you replace &emp;&emp; with &emp; in the following code: String a=null; if (a!=null && a.length()>10) { ... } A single ampersand here would lead to a NullPointerException. 2007-03-03, 5346👍, 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, 5271👍, 0💬

All rights in the contents of this web site are reserved by the individual author. fyicenter.com does not guarantee the truthfulness, accuracy, or reliability of any contents.