question: private static DownscaleQuality addConstant ( String type ) { init ( ) ; if ( constList . containsKey ( type ) ) { throw new RuntimeException ( "Type strings for DownscaleQuality should be unique; " + type + " is declared twice" ) ; } DownscaleQuality q = new DownscaleQuality ( type ) ; constList . put ( type , q ) ; return q ; }
target:  Create and add constant instance