Flow Control - SCJP Sun Certified Programmer for Java Platform SE6 - page 238

Now that we have discussed the details of the try statement, we can discuss the finally
keyword, which we use to create an optional block of code at the end of a try statement
that always executes after the code in the try block.

The finally Block

A try statement can be followed by a fi nally block . A finally block is a unique feature of
Java: it executes after a try statement, regardless of whether an exception occurs within the
try block. A finally block can only appear after a try statement and must appear at the
end of the catch clauses. Figure 3.12 shows the syntax for a finally block.

The syntax of a finally block

FIGURE 3.12

A finally block can only
appear as part of a try
statement.

try {

//protected code
} catch ( exceptiontype identifier ) {
//exception handler
} finally {
//finally block

} The finally block

always executes,
whether or not an
exception occurs
in the try block.

The finally keyword

A finally block allows you to perform any cleanup tasks that need to execute regardless
of what happens during the try block. For example, the following code closes a fi le after
attempting to read from it, whether or not the read is successful. Study the code carefully
and see if you can determine the output when no exception occurs:

1. import java.io.*;
2.
3. public class FinallyDemo {
4. public void readFromFile(String fileName) {
5. System.out.println(“Inside readFromFile”);
6. FileReader fis = null;
7. try {
8. fis = new FileReader(fileName);
9. char data = (char) fis.read();
10. System.out.println(“Just read: “ + data);