Page History

...

public class Operation {
  static void doOperation(String some_file) throws IOException {
    BufferedReader reader = new BufferedReader(new FileReader(some_file));

    try {
      // Do operations
    } finally {
      try {    
        // Enclose in try-catch block
        reader.close();
      } catch (IOException ie) {
        // Forward to handler
      }
      // Other clean-up code
    }
  }

  public static void main(String[] args) throws IOException {
    String path = "somepath";
    doOperation(path);
  }
}

While suppressing a caught exception normally violates ERR00-J. Do not suppress or ignore checked exceptions, this particular code would likelybe allowed under ERR00-EX0, as the reader would never be accessed again, so an error in closing it can not affect future program behavior.

Compliant Solution (

...

Dedicated Method to Handle Exceptions)

When closing a stream without throwing an exception is a frequent pattern in the code, an alternative solution is to use a closeHandlingException() method, as shown in this compliant solution.

public class Operation {
  static void doOperation(String some_file) throws IOException {
    BufferedReader reader = new BufferedReader(new FileReader(some_file));

    try {
      // Do operations
    } finally {
      closeHandlingException(reader);
      // Other clean-up code 
    }
  } 

  private static void closeHandlingException(BufferredReader s) {
    if (s != null) {
      try {
        s.close();
      } catch (IOException ie) {
        // IgnoreForward exception if close failsto handler
      }
    }
  }

  public static void main(String[] args) throws IOException {
    doOperation("somepath");
  }
}

While suppressing a caught exception normally violates ERR00-J. Do not suppress or ignore checked exceptions, this particular code would be allowed under ERR00-EX0, as the reader would never be accessed again, so an error in closing it can not affect future program behavior.

Risk Assessment

Failure to handle an exception in a finally block can lead to unexpected results.

...