Java Buzz Forum - try catch finally in java

try block:

The functionality of try keyword is to identify an exception object.
And catch that exception object and transfer the control along with the identified exception object to the catch block by suspending the execution of the try block.
All the statements which are proven to generate exceptions should be place in try block.

Syntax of try block:

try
{
//try block
//keep those statements which may
//throw run time exceptions
}

catch Block:

The functionality of catch block is to receive the exception class object that has been send by the "try".
And catch that exception class object and assigns that exception class object to the reference of the corresponding exception class defined in the catch block.
And handle the exception that has been identified by "try".
"try" block identifies an exception and catch block handles the identified exception.

Syntax:

catch(Exception e)
{
//catch block.
//one argument of type java.lang.Exception
//catches the exceptions thrown by try block
}

finally block:

finally blocks are the blocks which are going to get executed compulsorily irrespective of exceptions.
finally blocks are optional blocks.

Syntax:

finally
{
//This is the finally block.
}

Example Program:

package com.instanceofjava;
public class MyException {
public static void main(String a[]){
try{
int i = 10/0;
System.out.println("This statement won't executed");
}
catch(Exception ex){
System.out.println("This block is executed immediately after an exception is thrown");
}
finally{
System.out.println("This block is always executed");}
}
}

Output:

This block is executed immediately after an exception is thrown
This block is always executed.


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