question: public void writeField ( String name , String value ) throws IOException { if ( name == null ) { throw new IllegalArgumentException ( "Name cannot be null or empty." ) ; } out . writeBytes ( PREFIX ) ; out . writeBytes ( boundary ) ; out . writeBytes ( NEWLINE ) ; out . writeBytes ( "Content-Disposition: form-data; name=\"" + name + "\"" ) ; out . writeBytes ( NEWLINE ) ; out . writeBytes ( NEWLINE ) ; if ( value != null ) { out . writeBytes ( value ) ; } out . writeBytes ( NEWLINE ) ; out . flush ( ) ; }
target:  Writes a string field value.