question: public File ( String dirPath , String name ) { if ( name == null ) { throw new NullPointerException ( "name == null" ) ; } if ( dirPath == null || dirPath . isEmpty ( ) ) { this . path = fixSlashes ( name ) ; } else if ( name . isEmpty ( ) ) { this . path = fixSlashes ( dirPath ) ; } else { this . path = fixSlashes ( join ( dirPath , name ) ) ; } }
target:  Constructs a new File using the specified directory path and file name, placing a path separator between the two.