Deadlock: Deadlock is a situation when two threads are waiting for each other and the waiting never ends. Here both threads cant completes their tasks.
JAVA
// Java program to illustrate Deadlock situationclass DeadlockDemo extends Thread { static Thread mainThread; public void run() { System.out.println("Child Thread waiting for" + " main thread completion"); try { // Child thread waiting for completion // of main thread mainThread.join(); } catch (InterruptedException e) { System.out.println("Child thread execution" + " completes"); } } public static void main(String[] args) throws InterruptedException { DeadlockDemo.mainThread = Thread.currentThread(); DeadlockDemo thread = new DeadlockDemo(); thread.start(); System.out.println("Main thread waiting for " + "Child thread completion"); // main thread is waiting for the completion // of Child thread thread.join(); System.out.println("Main thread execution" + " completes"); }} |
Output:
Main thread waiting for Child thread completion Child Thread waiting for main thread completion
Starvation:In Starvation, threads are also waiting for each other. But here waiting time is not infinite after some interval of time, waiting thread always gets the resources whatever is required to execute thread run() method.
JAVA
// Java program to illustrate Starvation conceptclass StarvationDemo extends Thread { static int threadcount = 1; public void run() { System.out.println(threadcount + "st Child" + " Thread execution starts"); System.out.println("Child thread execution completes"); threadcount++; } public static void main(String[] args) throws InterruptedException { System.out.println("Main thread execution starts"); // Thread priorities are set in a way that thread5 // gets least priority. StarvationDemo thread1 = new StarvationDemo(); thread1.setPriority(10); StarvationDemo thread2 = new StarvationDemo(); thread2.setPriority(9); StarvationDemo thread3 = new StarvationDemo(); thread3.setPriority(8); StarvationDemo thread4 = new StarvationDemo(); thread4.setPriority(7); StarvationDemo thread5 = new StarvationDemo(); thread5.setPriority(6); thread1.start(); thread2.start(); thread3.start(); thread4.start(); // Here thread5 have to wait because of the // other thread. But after waiting for some // interval, thread5 will get the chance of // execution. It is known as Starvation thread5.start(); System.out.println("Main thread execution completes"); }} |
Output:
Main thread execution starts 1st Child Thread execution starts Child thread execution completes 2st Child Thread execution starts Child thread execution completes 3st Child Thread execution starts Child thread execution completes 4st Child Thread execution starts Child thread execution completes Main thread execution completes 5st Child Thread execution starts Child thread execution completes
