Handling Multiple Exceptions within a Method

Question

I am currently working on the maintenance of a piece of code that is a little bit "Exception Happy." Basically, ever method or anything throws Exception. I'm going to work to take care of that, but, in the meantime, I am wondering what is the best way to handle individual exceptions within a smaller block of code, such as a method. Is it better to do something like this:

public void aMethod()
  try {
    //Lots of code in here.  Many lines.
  } catch(Exception e) {
    // TODO - Handle All Exceptions, but fairly generically
  }
}

Or something like this:

public void bMethod() {
  try {
    // One line of code.
  } catch(Exception e) {
    // TODO - Handle a specific Exception (may even involve rethrowing it with more information)
  }

  // More code.

  try {
    // Another line of code.
  } catch(Exception e) {
    // TODO - Handle another specific exception.
  }
}

I realize this is a pretty basic question, but after looking at hundreds of methods with Exceptions coming out of every one, I'm starting to wonder how best to handle all of them and what a best practice may be here.

Answer 1

First off, you should only put code in try/catch blocks that is exception worthy. For instance, having an unexpected value is not necessarily an exception, but trying to read from a file that doesn't exist is.

To answer your main question, you should put the exceptionable code in the same try {} block and catch specific questions in order of granularity in multiple catch blocks after the main try.

//Regular code that doesn't need to be covered by a try/catch block

try {

  //critical code only

} catch (NullPointerException npe) {
  //Code
} catch (RandomException re) {
  //code
} catch (Exception e) {
  //code
}