rethrow exception

[vijay umar]

i read that if an checked exception is rethrown from the catch ... then we have to declare and handle it! both we have to do ..

so in this code ... how to declare and handle it! how the code will have to be altered..

public void doStuff() {
try {
// risky IO things
} catch(IOException ex) {
// can't handle it
throw ex; // Can't throw it unless you declare it
}
}

from k&s book...

[Bob Wheeler]

You have to declare OR handle EACH thrown exception. So you can either handle the rethrown exception like here:

  	public void doStuff() {
		try {
			throw new IOException();
		} catch(IOException ex) {
			try {                                   // HANDLE HERE
				throw ex;
			} catch (IOException e) {
				e.printStackTrace();
			} 
		}
		}
  

or declare the exception:

   
	public void doStuff() throws IOException{ // DECLARE HERE
		try {                                                   
			throw new IOException();
		} catch(IOException ex) {
			throw ex;
		}
	}
 

But be aware, if an instance calls the method doStuff() you have to declare OR handle the exception again.

cheers
Bob

[vijay umar]

ya! thanks! got it!

[vijay umar]

i am gonna write the scjp exam on 15th.... anything impotant you wish to telll me! that i should give some importance to! any questions any topics!

[Bob Wheeler]

vijay umar wrote:ya! thanks! got it!

welcome. good luck for your exam. check the time you need for one assignment.

cheers
Bob