question: public void testPBEKeySpec1 ( ) { try { PBEKeySpec pbeks = new PBEKeySpec ( null ) ; assertTrue ( "An empty char[] should be used in case of null " + "char array." , pbeks . getPassword ( ) . length == 0 ) ; } catch ( NullPointerException e ) { fail ( "Unexpected NullPointerException was thrown." ) ; } char [ ] password = new char [ ] { '1' , '2' , '3' , '4' , '5' } ; PBEKeySpec pbeks = new PBEKeySpec ( password ) ; password [ 0 ] ++ ; assertFalse ( "The change of password specified in the constructor " + "should not cause the change of internal array." , password [ 0 ] == pbeks . getPassword ( ) [ 0 ] ) ; }
target:  PBEKeySpec(char[] password) method testing. Tests the behavior of the method in the case of null input char array and tests that input array is copied during the object initialization.