Java Multi Thread Example

Java Program to show Multi Threading

class Ta extends Thread
{
public void run()
{
for(int i=1; i<=5; i++)
{
System.out.println("A thread=" + i);
}
System.out.println("Ta is over");
}
}

class Tb extends Thread
{
public void run()
{
for(int j=1; j<=5; j++)
{
System.out.println("B thread=" + j);
}
System.out.println("Tb is over");
}
}

class thread
{
public static void main(String args[])
{
Ta ta=new Ta();
ta.start();

Tb tb=new Tb();
tb.start();
}
}

Java Threading program to show use of stop() method

class Ta extends Thread
{
public void run()
{
    for(int i=1; i<=5; i++)
    {
    try 
    { 
    sleep(1000);
    }
    
    catch(Exception e) {}

System.out.println("Thread A= " + i);
}
System.out.println("Exit of Thread A");
}
}

class Tb extends Thread
{
public void run()
{
    for(int j=1; j<=5; j++)
    {
    if (j==3) 
    stop();
    System.out.println("Thread B= " + j);

    }
}
}

class thread2
{
public static void main(String args[])
{
Ta ta=new Ta();
ta.start();
Tb tb=new Tb();
tb.start();
}
}

Java Program to demonstrate Multi threading.

class Ta extends Thread
{
public void run()
{
    for (int i=1; i<=5; i++)
    {
    try
    {
    sleep(1000); 
    }
    catch(Exception e) {}

    System.out.println("Thread A is running="+i);
    }
System.out.println("Thread A is Stopped");
}
}

class Tb extends Thread
{
public void run()
{
    for (int j=1; j<=5; j++)
    {
    try
    {
    sleep(500); 
    } catch(Exception e) {}

System.out.println("Thread B is running="+j);
}
System.out.println("Thread B is Stopped");
}
}

class thread3
{
public static void main(String args[])
{
Ta ta=new Ta();
ta.start();

Tb tb=new Tb();
tb.start();
}
}

Java Program to demonstrate Thread Priority (MIN and MAX Priority)

class Ta extends Thread
{
public void run()
{
    for(int p=1; p<=5; p++)
    {
    try
    {
    sleep(500);
    }
    catch(InterruptedException e) { } 
    System.out.println("Thread is running=p: "+p);
    }
}
}

class Tb extends Thread
{
public void run()
{
    for(int q=1; q<=5; q++)
    {
    try
    {
    sleep(500);
    }
    catch(InterruptedException e) { } 
    System.out.println("Thread is running=q: "+q);
    }
}
}

class thread5
{
public static void main(String args[])
{
Ta ta=new Ta();
Tb tb=new Tb();

tb.setPriority(Thread.MAX_PRIORITY);
ta.setPriority(Thread.MIN_PRIORITY);

ta.start();
tb.start();

System.out.println("Main thread is stopped");
}
}

Java Program to demonstrate Synchronized thread.

class Tb extends Thread
{
int total;
public void run()
{
synchronized(this)
{
for(int i=0; i<10; i++)
{
    try
    {
    sleep(1000); 
    }
    catch(Exception e) {}

 total += i;
}
   notify();
     }
   }
}
public class thread6 
{
public static void main(String args[])
{
Tb b = new Tb();
b.start();
synchronized(b)
{
 try
{
System.out.println("Waiting for b to complete the calculation...");
b.wait();
}
catch(InterruptedException e){}
System.out.println("Total is: " + b.total);
 }
}
}

Java File handling example to show total no. of lines / strings present in the file.

import java.io.*;

public class NOL
{
public static void main(String[] args) 
{
try
{
System.out.println("Getting line number of a paritcular file example!");
 BufferedReader bf = new BufferedReader(new InputStreamReader(System.in));
 System.out.println("Please enter file name with extension:");
   String str = bf.readLine();
   File file = new File(str);
   if (file.exists())
{
    FileReader fr = new FileReader(file);
   LineNumberReader ln = new LineNumberReader(fr);
  int count = 0;
  while (ln.readLine() != null){
 count++;
  }
  System.out.println("Total line no: " + count);
 ln.close();
  }
 else{
  System.out.println("File does not exists!");
  }
 }
 catch(IOException e){
 e.printStackTrace();
 }
 }
}

import java.util.*;

public class rannum
{
public static void main(String[] args)
{
  Random rand = new Random();

  int num = rand.nextInt(20);
  System.out.println("Generated Random Number between 0 to 20 is : " + num);

  int numNoRange = rand.nextInt();
  System.out.println("Generated Random Number without specifying any range is : " + numNoRange);
}
}