Note: The * operator in Java programming language is used to multiply two numbers.

 //Method-1: Simple java program to find the product of two numbers.
public class Multiply1{
  public static void main (String[] args){

     System.out.println (2*3);
  }
}

 Save this file as 'Multiply1.java'
Compile: $javac Multiply1.java
Execute: $java Multiply1

 Output:
6


//Method-2: By declaring variables
public class Multiply2{
  public static void main (String[] abc){

     int num1 = 12;
    int num2 = 15;

     System.out.println ("First number = "+num1);
    System.out.println ("Second number = "+num2);

     int result = num1 * num2;

     System.out.println ("\nMultiplication of "+num1+" and "+num2+" = "+result);
  }
}

 Save this file as 'Multiply2.java'
Compile: $javac Multiply2.java
Execute: $java Multiply2

 Output:

 First number = 12
Second number = 15

 Multiplication of 12 and 15 = 180

 //Method-3: By using class and object method
class Multi1{

     int num1 = 12;
    int num2 = 5;

     //creating methods
    void m1(){

         System.out.println ("First number : "+num1);
        System.out.println ("Second number : "+num2);
    }

     void m2(){

         //compute Multiplication
        int result = num1 * num2;

         //printing result
        System.out.println ("\nMultiplication of "+num1+" and "+num2+" is : "+result);
    }
}

 public class Multiply3{

     public static void main(String[] abc){

         //creating new object
        Multi1 obj = new Multi1();
        //calling methods
        obj.m1();
        obj.m2();
    }
}

 Save this file as 'Multiply3.java'
Compile: $javac Multiply3.java
Execute: $java Multiply3

 Output:

 First number : 12
Second number : 5
Multiplication of 12 and 5 is : 60