Java Multithreading :
Java multithreading is a concept of doing multiple task at a same time.Thread is a light weight sub-process.Let’s see a example of how this concept is used in real time.
Consider a two classes Abc() and Def().And will use for loop to print numbers from 0 to 9
class Abc {
public void display(){
for (int i = 0; i < 10; i++) {
System.out.println("Abc " + i);
}
}
}
class Def {
public void display(){
for (int i = 0; i < 10; i++) {
System.out.println("Def " + i);
}
}
}
now try to print the for loops
public class TestExample {
public static void main(String args[]) {
Abc abc = new Abc();
abc.display();
Def def = new Def();
def.display();
}
}
Using threads:
Extend the classes Abc() and Def() with Thread class.
class Abc extends Thread {
@Override
public void run() {
super.run();
for (int i = 0; i < 10; i++) {
System.out.println("Abc " + i);
}
}
}
class Def extends Thread {
@Override
public void run() {
super.run();
for (int i = 0; i < 10; i++) {
System.out.println("Def " + i);
}
}
}
now start the threads and observer the output
public class TestExample {
public static void main(String args[]) {
Abc abc = new Abc();
abc.start();
Def def = new Def();
def.start();
}
}
We can use methods in thread like start(), sleep(), stop(), getState(), getPriority(), getName().
start() :
Is used to start a thread, entry point for the thread we have used in the above example.
Abc abc = new Abc(); abc.start();
sleep() :
Will provide a delay in between the Thread execution. We need to provide time delay to sleep method.
sleep(time duartion);
always to be enclosed in try catch
try {
sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
Example for sleep()
class Abc extends Thread {
@Override
public void run() {
super.run();
for (int i = 0; i < 10; i++) {
System.out.println("Abc " + i);
try {
sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
stop() :
This method is deprecated it was used to stop the thread, we should not stop the thread it will stop by itself.
class Abc extends Thread {
@Override
public void run() {
super.run();
for (int i = 0; i < 10; i++) {
System.out.println("Abc " + i);
if(i == 6)
stop();
}
}
}
getState() :
Get the state of the thread
System.out.println("Thread state: "+abc.getState());
getName():
Get the name of the thread
System.out.println("Thread name: "+abc.getName());
getPriority() :
Get the priority of the thread
System.out.println("Thread priority: "+abc.getPriority());
