Java Disposable pattern

Question

C# supports disposable pattern for deterministic garbage collection using the dispose pattern.

Is there such pattern for java?

Java 7 has autoclosable, whic

Answer 1

The closest prior to Java 7 is just "manual" try/finally blocks:

FileInputStream input = new FileInputStream(...);
try {
  // Use input
} finally {
  input.close();
}

The using statement was one of the things I found nicest about C# when I first started using C# 1.0 from a Java background. It's good to see it finally in Java 7 :)

You should also consider Closeables in Guava - it allows you to not worry about whether or not a reference is null (just like a using statement does) and optionally "logs and swallows" exceptions thrown when closing, to avoid any such exception from effectively "overwriting" an exception thrown from the try block.

Answer 2

What you are looking for is try with resources.

try ( FileInputStream input = new FileInputStream(...);
      BufferedReader br = new BufferedReader(...) ) {
  // Use input
} 

The resource has to be Closeable (or AutoCloseable), of course.

Answer 3

The entire purpose of the disposal pattern is to support C#'s unique using (temporaryObject) pattern. Java has had nothing like that pattern before 7.

All Java objects that had resources supported the disposal pattern via manually closing the object that held resources.