Thread Communication:
In some case,two or more threads should communicate with each-other.for example,a consumer thread is waiting for a producer to produce the data.when the producer thread completes production of data,then the consumer thread should take that data and use it.
Program:
/**
*
*/
/**
* @author Abhinaw.Tripathi
*
*/
class Producer extends Thread
{
StringBuffer sb;
boolean dataprodover=false;
public Producer()
{
sb=new StringBuffer();
}
public void run()
{
for(int i=0;i<=10;i++)
{
sb.append(i+":");
try
{
Thread.sleep(100);
System.out.println("Appending");
}
catch (InterruptedException e)
{
e.printStackTrace();
}
}
dataprodover=true;
}
}
class Consumer extends Thread
{
Producer prod;
public Consumer(Producer prod)
{
this.prod=prod;
}
public void run()
{
while(!prod.dataprodover)
try
{
Thread.sleep(10);
}
catch (InterruptedException e)
{
e.printStackTrace();
}
System.out.println(prod.sb);
}
}
public class ProducerConsumerApp
{
public static void main(String[] args) {
Producer obj1=new Producer();
Consumer obj2=new Consumer(obj1);
Thread t1=new Thread(obj1);
Thread t2=new Thread(obj2);
t1.start();
t2.start();
}
}
Output:
Appending
Appending
Appending
Appending
Appending
Appending
Appending
Appending
Appending
Appending
Appending
0:1:2:3:4:5:6:7:8:9:10:
Here we can improve the efficiency of communication between threads?using 3 methods:
obj.notify();
obj.notifyAll();
obj.wait();
So we can use these methods inside the synchronize method.
What is difference between sleep() and wait() method?
Ans: Both sleep and wait methods are used to suspend a thread execution for a specified time.When sleep() is executed inside a synchronized block,the object is still under lock.when wait() method is executed,it breaks the synchronized block,So that the object lock is removed and it is available.
Generally,sleep() is used for making a thread to wait for some time.But wait() is used in connection with notify() or notifyAll() methods in thread communication.