Java arcgis获取多段线的交点

我想使用esri中的arcgis java apie在arcgis中绘制多边形线相交的点

我已经写了这样的代码来检查是否有线相交

Polyline polyline = new Polyline();
polyline.startPath(118.169, 34.016);
polyline.lineTo(120.941, 39.7072);

SimpleLineSymbol symbol = new SimpleLineSymbol(Color.MAGENTA, 8);
symbol.setStyle(SimpleLineSymbol.Style.SOLID);

Graphic graphic = new Graphic(polyline, symbol);
graphicsLayer.addGraphic(graphic);

Polyline polyline2 = new Polyline();
polyline2.startPath(150.169, 34.016);
polyline2.lineTo(90.941, 39.7072);

SimpleLineSymbol symbol2 = new SimpleLineSymbol(Color.BLACK, 8);
symbol2.setStyle(SimpleLineSymbol.Style.SOLID);

Graphic graphic2 = new Graphic(polyline2, symbol2);
graphicsLayer.addGraphic(graphic2);

Polyline intersection = (Polyline)GeometryEngine.intersect(polyline, polyline2, srMap);
System.out.println(intersection.getPointCount());
System.out.println(GeometryEngine.intersects(polyline, polyline2, srMap));

第一个打印行返回0，但第二个打印行返回true。如何在arcgis中获取千个交点