Exception Handling

What is an Exception ?

Let us see what happens when an exception occurs and is not handled properly

When you compile and run the following program

public class Test{
   public static void main(String str[]){
      int y = 0;
      int x = 1;
      // a division by 0 occurs here.
      int z = x/y;
      System.out.println("after didvision");
   }
}

the execution of the Test stops and this is caused by the division by zero at - x/y - an exception has been thrown but has not been handled properly.

How to handle an Exception ?

To handle an Exception, enclose the code that is likely to throw an exception in a try block and follow it immediately by a catch clause as follows

public class Test{
   public static void main(String str[]){
      int y = 0;
      int x = 1;
      // try block to "SEE" if an exception occurs
      try{
         int z = x/y;
  System.out.println("after didvision");
         // catch clause below handles the
  // ArithmeticException generated by
         // the division by zero.
      }  catch (ArithmeticException ae)
  {System.out.println(" attempt to divide by 0");}
      System.out.println(" after catch ");
   }
}

The output of the above program is as follows

attempt to divide by 0
after catch

the statement - System.out.println("after didvision") - is NOT executed, once an exception is thrown, the program control moves out of the try block into the catch block.

More Java Questions

• Java Exception Handling
• Java Packages and interface
• Java Control Statements

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