try-catch-finally

In a Java try{} ... catch{} ... finally{} block, code within the finally{} is generally considered "guaranteed" to run regardless of what occurs in the try/catch. However, I know of at least two circumstances under which it will not execute: If System.exit(0) is called; or, if an Exception is thrown all the way up to the JVM and the default behavior occurs (i.e., printStackTrace() and exit) Are there any other program behaviors that will prevent the code in a finally{} block from executing? Under what specific conditions will the code execute or not? EDIT: As NullUserException pointed out, the

I never properly understood the use of the finally statement. Can anyone tell me what the difference is between: try { a; block; off; statements; } catch (Exception e) { handle; exception; e; } finally { do; some; cleanup; } on the one hand and: try { a; block; off; statements; } catch (Exception e) { handle; exception; e; } do; some; cleanup; On the other They differ if the try -block completes by throwing a java.lang.Throwable that is not a java.lang.Exception , for instance because it is a java.lang.Error such as AssertionError or OutOfMemoryError . the try-block completes abruptly using a

This question already has an answer here: Why do we use finally blocks? 10 answers Why do this } catch (SQLException sqle) { sqle.printStackTrace(); } finally { cs.close(); rs.close(); } Instead of this } catch (SQLException sqle) { sqle.printStackTrace(); } rs.close(); cs.close(); Because if an exception gets thrown no code after the try block is executed unless the exception is caught. A finally block is always executed no matter what happens inside your try block. Look at your catch block - it's going to throw DAOException . So the statements after your catch block aren't going to be

I'm reviewing some new code. The program has a try and a finally block only. Since the catch block is excluded, how does the try block work if it encounters an exception or anything throwable? Does it just go directly to the finally block? If any of the code in the try block can throw a checked exception, it has to appear in the throws clause of the method signature. If an unchecked exception is thrown, it's bubbled out of the method. The finally block is always executed, whether an exception is thrown or not. Peter Lawrey A small note on try / finally : The finally will always execute unless

I have seen people say that it is bad form to use catch with no arguments, especially if that catch doesn't do anything: StreamReader reader=new StreamReader("myfile.txt"); try { int i = 5 / 0; } catch // No args, so it will catch any exception {} reader.Close(); However, this is considered good form: StreamReader reader=new StreamReader("myfile.txt"); try { int i = 5 / 0; } finally // Will execute despite any exception { reader.Close(); } As far as I can tell, the only difference between putting cleanup code in a finally block and putting cleanup code after the try..catch blocks is if you

Please see the following code and explain the output behavior. public class MyFinalTest { public int doMethod(){ try{ throw new Exception(); } catch(Exception ex){ return 5; } finally{ return 10; } } public static void main(String[] args) { MyFinalTest testEx = new MyFinalTest(); int rVal = testEx.doMethod(); System.out.println("The return Val : "+rVal); } } The result is the return Val : 10. Eclipse shows a warning: finally block does not complete normally . What happens to the return statement in catch block ? It is overridden by the one in finally , because finally is executed after