10. Why wait(), notify(), and notifyAll() methods are present in
Object class?
We know that every object has a monitor that allows the thread to hold a lock on the
object. But the thread class doesn't contain any monitors. Thread usually waits for
the object’s monitor (lock) by calling the wait() method on an object, and notify other
threads that are waiting for the same lock using notify() or notifyAll() method.
Therefore, these three methods are called on objects only and allow all threads to
communicate with each that are created on that object.
11. What is Runnable and Callable Interface? Write the
difference between them.
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Multithreading Interview Questions
Both the interfaces are generally used to encapsulate tasks that are needed to be
executed by another thread. But there are some differences between them as given
below:
Running Interface: This interface is basically available in Java right from the
beginning. It is simply used to execute code on a concurrent thread.
Callable Interface: This interface is basically a new one that was introduced as a part
of the concurrency package. It addresses the limitation of runnable interfaces along
with some major changes like generics, enum, static imports, variable argument
method, etc. It uses generics to define the return type of object.
public interface
Runnable
{
public abstract void
run
();
}
public interface
Callable
<
V
>
{
V
call
() throws Exception;
}
Runnable Interface vs Callable Interface
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