Java Finally


The finally block always executes when the try block exits. This ensures that the finally block is executed even if an unexpected exception occurs. But finally is useful for more than just exception handling — it allows the programmer to avoid having cleanup code accidentally bypassed by a return, continue, or break.

Putting cleanup code in a finally block is always a good practice, even when no exceptions are anticipated. It is also useful for closing connections in case of an unexpected exception, for example, it can close an open database connection if an exception is thrown during the try block.

Example

try { // Normal execution path throw new EmptyStackException(); } catch (ExampleException ee) { // deal with the ExampleException } finally { // This optional section is executed upon termination of any of the try or catch blocks above, // except when System.exit() is called in "try" or "catch" blocks; }

The finally block does not need the catch block to precede it.There can also be a finally block without the catch block.

Example

try { //Normal code System.out.println("hello world!"); } finally { System.out.println("In finally block"); }

Example

try { //Try to execute a query that can throws an exception stmt.executeUpdate( "INSERT INTO MyTable( name ) VALUES ( 'my name' ) " ); } finally { //Close the DB connection even in case of problem stmt.close(); }

The above code works fine even though the catch statement is not used.

Note: If program exits abnormally (ie. System.exit() or process aborts), finally block will not be executed.

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