question: private String validateInputs ( ) { String pomPath = pathEntry . getText ( ) ; if ( Strings . isNullOrEmpty ( pomPath ) ) { return "GraphML file cannot be empty" ; } File pathFile = new File ( pomPath ) ; if ( ! pathFile . exists ( ) ) { return "GraphML file doesn't exist" ; } return null ; }
target:  Determine if the page has been filled in correctly.