World Wind Java开发之十三——加载Geoserver发布的WMS服务(转)

时间:2022-03-15 11:15:21

这篇是转载的平常心博客,原地址见:http://www.v5cn.cn/?p=171

1、WMSTiledImageLayer类说明

一个WMSTiledImageLayer类对象只能对应一个WMS发布的服务图层,使用WMS服务时需要使用到WMS元数据描述类WMSCapabilities对象,我们使用WMSCapabilites类的静态方法retrieve来获得它的对象。WMSCapabilites对象可以包含WMS服务中所以的图层和图层样式,我们通过把需要显示的图层名称保存到AVList对象中,然后通过WMSCapabilites对象和AVList来创建WMSTiledImageLayer对象。我们可以通过一个请求地址来查看WMS服务所包含的元数据。例如:http://127.0.0.1:8080/geoserver/PostGIS/wms?request=GetGapabilities&Service=WMS 问号后面的地址是固定的,可以但看如下的XML:

  1. <LayerqueryableLayerqueryable="1">
  2. <Name>spearfish</Name>
  3. <Title>spearfish</Title>
  4. <Abstract>Layer-Group type layer: spearfish</Abstract>
  5. <CRS>EPSG:26713</CRS>
  6. <EX_GeographicBoundingBox>
  7. <westBoundLongitude>-103.87791475407893</westBoundLongitude>
  8. <eastBoundLongitude>-103.62278893469492</eastBoundLongitude>
  9. <southBoundLatitude>44.37246687108142</southBoundLatitude>
  10. <northBoundLatitude>44.50235105543566</northBoundLatitude>
  11. </EX_GeographicBoundingBox>
  12. <BoundingBoxCRSBoundingBoxCRS="EPSG:26713"minx="589425.9342365642"miny="4913959.224611808"maxx="609518.6719560538"maxy="4928082.949945881"/>
  13. </Layer>
  14. <LayerqueryableLayerqueryable="1">
  15. <Name>tasmania</Name>
  16. <Title>tasmania</Title>
  17. <Abstract>Layer-Group type layer: tasmania</Abstract>
  18. <CRS>EPSG:4326</CRS>
  19. <EX_GeographicBoundingBox>
  20. <westBoundLongitude>143.83482400000003</westBoundLongitude>
  21. <eastBoundLongitude>148.47914100000003</eastBoundLongitude>
  22. <southBoundLatitude>-43.648056</southBoundLatitude>
  23. <northBoundLatitude>-39.573891</northBoundLatitude>
  24. </EX_GeographicBoundingBox>
  25. <BoundingBoxCRSBoundingBoxCRS="EPSG:4326"minx="-43.648056"miny="143.83482400000003"maxx="-39.573891"maxy="148.47914100000003"/>
  26. </Layer>
  27. <LayerqueryableLayerqueryable="1">
  28. <Name>tiger-ny</Name>
  29. <Title>tiger-ny</Title>
  30. <Abstract>Layer-Group type layer: tiger-ny</Abstract>
  31. <CRS>EPSG:4326</CRS>
  32. <EX_GeographicBoundingBox>
  33. <westBoundLongitude>-74.047185</westBoundLongitude>
  34. <eastBoundLongitude>-73.907005</eastBoundLongitude>
  35. <southBoundLatitude>40.679648</southBoundLatitude>
  36. <northBoundLatitude>40.882078</northBoundLatitude>
  37. </EX_GeographicBoundingBox>
  38. <BoundingBoxCRSBoundingBoxCRS="EPSG:4326"minx="40.679648"miny="-74.047185"maxx="40.882078"maxy="-73.907005"/>
  39. </Layer>
  40. <LayerqueryableLayerqueryable="1">
  41. <Name>省界_region</Name>
  42. <Title>省界_region</Title>
  43. <Abstract/>
  44. <KeywordList>
  45. <Keyword>features</Keyword>
  46. <Keyword>省界_region</Keyword>
  47. </KeywordList>
  48. <CRS>EPSG:4326</CRS>
  49. <CRS>CRS:84</CRS>
  50. <EX_GeographicBoundingBox>
  51. <westBoundLongitude>73.441277</westBoundLongitude>
  52. <eastBoundLongitude>135.08693</eastBoundLongitude>
  53. <southBoundLatitude>18.159829</southBoundLatitude>
  54. <northBoundLatitude>53.561771</northBoundLatitude>
  55. </EX_GeographicBoundingBox>
  56. <BoundingBoxCRSBoundingBoxCRS="CRS:84"minx="73.441277"miny="18.159829"maxx="135.08693"maxy="53.561771"/>
  57. <BoundingBoxCRSBoundingBoxCRS="EPSG:4326"minx="18.159829"miny="73.441277"maxx="53.561771"maxy="135.08693"/>
  58. <Style>
  59. <Name>polygon_x</Name>
  60. <Title>Default Polygon</Title>
  61. <Abstract>A sample style that draws a polygon</Abstract>
  62. <LegendURLwidthLegendURLwidth="20"height="20">
  63. <Format>image/png</Format>
  64. <OnlineResourcexmlns:xlinkOnlineResourcexmlns:xlink="http://www.w3.org/1999/xlink"xlink:type="simple"xlink:href="http://localhost:8080/geoserver/cite/ows?service=WMS&request=GetLegendGraphic&format=image%2Fpng&width=20&height=20&layer=%3F%3F_region"/>
  65. </LegendURL>
  66. </Style>
  67. </Layer>

里面的每一个Layer节点都是一个WMS图层。

2、例子

  1. package gov.nasa.worldwindx.v5cn;
  2. import gov.nasa.worldwind.avlist.AVKey;
  3. import gov.nasa.worldwind.avlist.AVList;
  4. import gov.nasa.worldwind.avlist.AVListImpl;
  5. import gov.nasa.worldwind.ogc.wms.WMSCapabilities;
  6. import gov.nasa.worldwind.wms.WMSTiledImageLayer;
  7. import gov.nasa.worldwindx.examples.ApplicationTemplate;
  8. import java.net.URI;
  9. import java.net.URISyntaxException;
  10. public class WMSLayerTest extends ApplicationTemplate {
  11. public static class AppFrame extends ApplicationTemplate.AppFrame{
  12. private static final long serialVersionUID = 1L;
  13. public AppFrame(){
  14. try {
  15. //请求地图的URL
  16. String uri = "http://127.0.0.1:8080/geoserver/PostGIS/wms";
  17. WMSCapabilities caps;
  18. URI serverURI = new URI(uri);
  19. //获得WMSCapabilities对象
  20. caps = WMSCapabilities.retrieve(serverURI);
  21. //解析WMSCapabilities数据
  22. caps.parse();
  23. AVList params = new AVListImpl();
  24. //图层的名称
  25. params.setValue(AVKey.LAYER_NAMES, "planet_osm_line");
  26. //地图服务的协议,这里是OGC:WMS
  27. params.setValue(AVKey.SERVICE_NAME, "OGC:WMS");
  28. //获得地图的uri,也就是上面定义的uri
  29. params.setValue(AVKey.GET_MAP_URL, uri);
  30. //在本地缓存文件的名称
  31. params.setValue(AVKey.DATA_CACHE_NAME, "planet_osm_line");
  32. params.setValue(AVKey.TILE_URL_BUILDER, new WMSTiledImageLayer.URLBuilder(params));
  33. WMSTiledImageLayer imageLayer = new WMSTiledImageLayer(caps,params);
  34. //图层名称
  35. imageLayer.setName("planet_osm_line");
  36. imageLayer.setEnabled(true);
  37. //图层的透明度
  38. imageLayer.setOpacity(1);
  39. //图层的最大显示高度
  40. imageLayer.setMaxActiveAltitude(33500000);
  41. getWwd().getModel().getLayers().add(imageLayer);
  42. getLayerPanel().update(getWwd());
  43. } catch (URISyntaxException e) {
  44. e.printStackTrace();
  45. } catch (Exception e) {
  46. e.printStackTrace();
  47. }
  48. }
  49. }
  50. public static void main(String[] args) {
  51. ApplicationTemplate.start("WMS图层", WMSLayerTest.AppFrame.class);
  52. }
  53. }

请求的URL就是GeoServer中点击【OpenLayers】中的路径:

图层名称就是定义发布服务是的名称,可以在GeoServer中找到。