Throwing exception from within catch and also from finally block

Question

I want to throw any exception that occurs while doing MySQL transaction to the application. But before that I want to close any resources that are in open state. But closing these resources might again generate exception which again I would want to report to application. The following code will make this a little clear:

try
{
   // connect to MySQL DB using JDBC and run different queries
}
catch ( Exception e )
{
   // throw this exception by wrapping it in another user defined exception class
}
finally
{
   try
   {
      // close resources opened in try block ( statement, connection )
   }
   catch ( Exception e )
   {
      // throw this exception by wrapping it in another user defined exception class
   }   
}

I want to know what is the correct way to handle this situation ( having two exception being thrown ). Thanks for your help.

Which version of Java you are working on?

Rahul Tripathi
– Rahul Tripathi

2014-08-21 09:17:06 +00:00
Commented Aug 21, 2014 at 9:17 — Rahul Tripathi
– Rahul Tripathi, Commented Aug 21, 2014 at 9:17
The java version I am using is 1.6.0_22

Vimal
– Vimal

2014-08-21 10:43:42 +00:00
Commented Aug 21, 2014 at 10:43 — Vimal
– Vimal, Commented Aug 21, 2014 at 10:43

Braj · Accepted Answer · 2014-08-21 09:09:48Z

1

I suggest you to use Java 7 The try-with-resources Statement

It's better explained in Oracle Documentation on

Better Resource Management with Java SE 7: Beyond Syntactic Sugar

sample code:

try(  Connection conn = dataSource.getConnection();
      PreparedStatement stmt = conn.prepareStatement(query);
      ResultSet rs = stmt.executeQuery() ) {
     // connection, statements and result set are automatically closed 
}

Note: A try-with-resources statement can have catch and finally blocks just like an ordinary try statement. In a try-with-resources statement, any catch or finally block is run after the resources declared have been closed.

edited Aug 21, 2014 at 9:09

answered Aug 21, 2014 at 8:55

Braj

46.9k5 gold badges63 silver badges77 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Vimal Over a year ago

This looks to me a promising solution. We are still using Java 6 here but I will definitely find out more about this.

Rahul Tripathi · Accepted Answer · 2014-08-21 08:55:00Z

1

You may try like this:

try
{
   // connect to MySQL DB using JDBC and run different queries
}
catch ( Exception e )
{
   // throw this exception by wrapping it in another user defined exception class
}
finally
{
  closeMyConnection(resource);
}

protected void closeMyConnection( Resource resource ) {
  try {
    if (resource != null) {
      resource.close();
    }
  } catch( Exception ex ) {
    log( "There is some excetion", ex );
  }
}

answered Aug 21, 2014 at 8:55

Rahul Tripathi

173k33 gold badges292 silver badges341 bronze badges

1 Comment

Vimal Over a year ago

Thanks R.T. for you help. Basically then what should happen is that any exception thrown within finally should get handled where it is thrown and the original exception ( or any other return value ) should be passed back to application. I hope this is how most applications would work. Alas I can mark only one solution as accepted. But thanks to everyone for their efforts and help.

Scary Wombat · Accepted Answer · 2014-08-21 08:55:27Z

1

try

Exception lastException = null:
try
{
   // connect to MySQL DB using JDBC and run different queries
}
catch ( Exception e )
{
   // throw this exception by wrapping it in another user defined exception class
   lastException = e;
}

if (lastException != null) {
  // you know what to do
}

answered Aug 21, 2014 at 8:55

Scary Wombat

44.9k6 gold badges38 silver badges67 bronze badges

Collectives™ on Stack Overflow

Throwing exception from within catch and also from finally block

3 Answers 3

1 Comment

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

1 Comment

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related