question: private Figure readLineElement ( IXMLElement elem ) throws IOException { HashMap < AttributeKey , Object > a = new HashMap < AttributeKey , Object > ( ) ; readCoreAttributes ( elem , a ) ; readTransformAttribute ( elem , a ) ; readOpacityAttribute ( elem , a ) ; readLineAttributes ( elem , a ) ; if ( FILL_COLOR . get ( a ) != null && STROKE_COLOR . get ( a ) == null ) { STROKE_COLOR . put ( a , FILL_COLOR . get ( a ) ) ; } if ( FILL_GRADIENT . get ( a ) != null && STROKE_GRADIENT . get ( a ) == null ) { STROKE_GRADIENT . put ( a , FILL_GRADIENT . get ( a ) ) ; } FILL_COLOR . put ( a , null ) ; FILL_GRADIENT . put ( a , null ) ; double x1 = toNumber ( elem , readAttribute ( elem , "x1" , "0" ) ) ; double y1 = toNumber ( elem , readAttribute ( elem , "y1" , "0" ) ) ; double x2 = toNumber ( elem , readAttribute ( elem , "x2" , "0" ) ) ; double y2 = toNumber ( elem , readAttribute ( elem , "y2" , "0" ) ) ; Figure figure = factory . createLine ( x1 , y1 , x2 , y2 , a ) ; elementObjects . put ( elem , figure ) ; return figure ; }
target:  Reads an SVG "line" element.