Throwing an exception from within a finally block will mask any exception which was previously thrown in the try or catch block.

The masked's exception message and stack trace will be lost.

Noncompliant Code Example

try {
  /* some work which end up throwing an exception */
  throw new IllegalArgumentException();
} finally {
  /* clean up */
  throw new RuntimeException();       // Noncompliant; will mask the IllegalArgumentException
}

Compliant Solution

try {
  /* some work which end up throwing an exception */
  throw new IllegalArgumentException();
} finally {
  /* clean up */                                         // Compliant
}

See

• CERT, ERR05-J. - Do not let checked exceptions escape from a finally block