如果我们同时尝试进行资源清理，是否可以避免finally阻塞？

Question

Can we avoid finally block if we do resource cleanup in both try and catch together ?

Eg Can we do something like this and not use finally?

try{
 // Some statements
 db.close();
}catch(Exception e){
 db.close();
}

Will it work as expected? If Yes then Why should or shouldn't we use it?

Answer 1

Just use try-with-resources :

try(Connection db = getConnection()){
    //perform stuff
}

once the try block has finished processing the Connection will be closed.

Answer 2

Yes we can. But why you want to call the same code twice instead of having single call which will be executed in any case?

For the best practices see this question Java try/catch/finally best practices while acquiring/closing resources

Answer 3

这可以按预期工作，但是它会重复代码，这意味着，如果您想更改“最终零件代码”，则必须将代码更改两次，而不是将其放入finally块中一次。

Answer 4

Yes it will work. Finally block is basically used for the common operations in the try/catch . But think about it you have 10-20 common statement in both try and catch. Then what it will look like? Finally block help you to remove redundancy of your code.

Answer 5

Use try-with-resources wherever possible or try-finally (try-catch-finally).

Can we avoid finally block if we do resource cleanup in both try and catch together?

Why? You could, by substituting a well working and for this purpose designed java idiom by errorneous code and by using some antipatterns.

Assuming, your are going to log or handle exceptions in real life, this is why your code is not the same:

Not working:

• your connection is not always closed, since you are only handling exceptions, no errors or throwables

Some antipatterns:

• You are re-inventing the wheel
• DRY (don't repeat yourself)
• Catch the most specific exceptions first; avoid handling Exception, Error or Throwable in general
• be aware of swallowing exceptions (possible with finally, too!), try-with-resources is using suppressed exceptions for this
• ...