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If a finally clause is specified, irrespective of whether the try or catch block executes blocks execute to completion or not, the finally block is executed. Consequently, statements that cause the finally block to terminate abruptly may mask any thrown exceptions. Hence, keywords Keywords like return, break, continue and throw should never be used within a finally block.

Noncompliant Code Example

HereIn this noncompliant code example, the finally block completes abruptly because a return statement occurs within itits body. As a result, when the IllegalStateException is thrown, it does not propagate all the way up through the call stack. This is because of the abrupt termination of the finally block that suppresses any useful exception information from being displayed by as a result of overriding the exception thrown in the try block. Note that even if the try block returns some value, the finally block is executed.

class TryFinally {              
  private static boolean doLogic() {
    try {
      throw new IllegalStateException(); 
    } 
    finally {
      System.out.println("Uncaught Exception");
      return true;
    }
  }

  public static void main(String[] args) {
    doLogic();	
  }
}

Note that even if the try block returns some value, the finally block is executed.

Compliant Solution

This compliant solution removes the return statement from the finally block. Any return statements must occur after this block. If this is adopted, the compiler throws an error as the return statement is unreachable because of the explicit, unavoidable throwing of IllegalStateException. If the exception is thrown conditionally, the return statement can be used without any compilation errors.

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Exiting abruptly from a finally block may cause result in the masking of thrown exceptions.

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