Server Java讲座--动态添加图层数据

有的时候，特别是在做分析时，需要经常添加新的图层到当前的地图中。在这个时候，我们一般采用非池化的Server Object，以保证当前用户的修改不会影响到其他用户。添加图层的代码如下：
首选，得到Resource和mapFunctionality和MapServerInfo，以备后面使用：

AGSLocalMapResource gisrec=(AGSLocalMapResource)webContext.getResources().get(
"ags1"
);
AGSMapFunctionalitymapfunction=(AGSMapFunctionality)gisrec.getFunctionalities().get(
"map"
);
MapServerPortmapServer=gisrec.getMapServer();
MapServerInfoserverInfo=mapServer.getServerInfo(mapServer.getDefaultMapName());

AGSLocalMapResource gisrec=(AGSLocalMapResource)webContext.getResources().get("ags1");
AGSMapFunctionalitymapfunction=(AGSMapFunctionality)gisrec.getFunctionalities().get("map");
MapServerPortmapServer=gisrec.getMapServer();
MapServerInfoserverInfo=mapServer.getServerInfo(mapServer.getDefaultMapName());

得到MapServer的IMap接口

IMaptargetMap=gisrec.getLocalMapServer().getMap(gisrec.getLocalMapServer().getDefaultMapName());

IMaptargetMap=gisrec.getLocalMapServer().getMap(gisrec.getLocalMapServer().getDefaultMapName());

IMap接口可以用来添加数据到ServerObject。下面的代码可以用来从文件数据库中读取数据并把它添加到IMap中：

IWorkspacewk=
this
.connectToFileDB(
"D:\\data\\sapdata.gdb"
,gisrec.getServerContext());
IFeatureClassfc=
this
.getFeatureclass(wk,
"MSA_Intersect"
);
FeatureLayerflayer=(FeatureLayer)gisrec.getServerContext().createObject(FeatureLayer.getClsid());
flayer.setFeatureClassByRef(fc);
targetMap.addLayer(flayer);

IWorkspacewk=this.connectToFileDB("D:\\data\\sapdata.gdb",gisrec.getServerContext());
IFeatureClassfc=this.getFeatureclass(wk,"MSA_Intersect");
FeatureLayerflayer=(FeatureLayer)gisrec.getServerContext().createObject(FeatureLayer.getClsid());
flayer.setFeatureClassByRef(fc);
targetMap.addLayer(flayer);

里面用到的两个function的代码如下：

public
 IWorkspace connectToFileDB(StringfileGDB,IServerContext sc) 
throws
 java.net.UnknownHostException,java.io.IOException{
com.esri.arcgis.datasourcesGDB.FileGDBWorkspaceFactoryfactory = (FileGDBWorkspaceFactory)sc.createObject(FileGDBWorkspaceFactory.getClsid());
com.esri.arcgis.geodatabase.IWorkspaceworkspace = factory.openFromFile(fileGDB,
0
);
return
 workspace;

}

publicIFeatureClass getFeatureclass(IWorkspace workspace,String fName) throwsjava.net.UnknownHostException, java.io.IOException{
com.esri.arcgis.geodatabase.IEnumDatasetenumDataset =workspace.getDatasets(com.esri.arcgis.geodatabase.esriDatasetType.esriDTFeatureClass);
com.esri.arcgis.geodatabase.IDatasetds = 
null
;
ds= enumDataset.next();
while
(ds!= 
null
){
if
(ds.getName().endsWith(fName)){
return
new
 IFeatureClassProxy(ds);
}
ds= enumDataset.next();

}

retur nnull;

}

public IWorkspace connectToFileDB(StringfileGDB,IServerContext sc) throws java.net.UnknownHostException,java.io.IOException{
com.esri.arcgis.datasourcesGDB.FileGDBWorkspaceFactoryfactory = (FileGDBWorkspaceFactory)sc.createObject(FileGDBWorkspaceFactory.getClsid());
com.esri.arcgis.geodatabase.IWorkspaceworkspace = factory.openFromFile(fileGDB,0);
return workspace;

}

publicIFeatureClass getFeatureclass(IWorkspace workspace,String fName) throwsjava.net.UnknownHostException, java.io.IOException{
com.esri.arcgis.geodatabase.IEnumDatasetenumDataset =workspace.getDatasets(com.esri.arcgis.geodatabase.esriDatasetType.esriDTFeatureClass);
com.esri.arcgis.geodatabase.IDatasetds = null;
ds= enumDataset.next();
while(ds!= null){
if(ds.getName().endsWith(fName)){
return
new IFeatureClassProxy(ds);
}
ds= enumDataset.next();

}

retur nnull;

}

添加图层到ServerObject后，调用下面的代码，让修改生效。调用下面的代码后，将会使ServerObject的状态发生改变。

gisrec.getLocalMapServer().refreshServerObjects();

Server Object状态改变后，需要重新得到serverInfo，并且设置MapFunctionality里面的LayerDescription，把新的layer加入进去。这里我们就不手工添加，而是直接把整个MapDescription设置一遍，如下面的代码所示：

serverInfo=mapServer.getServerInfo(mapServer.getDefaultMapName());
mapfunction.getMapServerInfo().setDefaultMapDescription(serverInfo.getDefaultMapDescription());
mapfunction.setMapDescription(serverInfo.getDefaultMapDescription());

serverInfo=mapServer.getServerInfo(mapServer.getDefaultMapName());
mapfunction.getMapServerInfo().setDefaultMapDescription(serverInfo.getDefaultMapDescription());
mapfunction.setMapDescription(serverInfo.getDefaultMapDescription());

最后，当然要加上一句refresh context的代码:

webContext.refresh();

webContext.refresh();

把此代码放在一个tool或者command中运行即可。这应该是最简洁明了的添加一个图层的代码了。