Below demonstrates the implementation of the service interface:

@Interface(componentTypes = { com.supermap.services.components.Map.class }, optional = false, multiple = false)

@Protocol(names={"BingMaps"})

public class BingMapsServlet extends HttpServlet implements InterfaceContextAware {

        ...

}

Where

  • The service interface implementation class needs to be a Servlet, which is implemented by being inherited from HttpServlet. InterfaceContextAware, which is the service interface context interface, is used to get the configuration information of the service components and service interfaces.

    Service Interface context

    In the implementation class of the service interface, InterfaceContextAware can be used to get the service interface context, through which the service components and the configuration information of the service interfaces can be got.

    Getting Service Interface configuration

    The configuration inforamtion of the service interfaces is in iserver-services-interfaces.xml. (refer to Structure of Service Configure File) Below is the configuration for one service interface:

    <interface class="com.supermap.sample.SampleServlet" name="sampleinterface">

            <config class="com.supermap.sample.SampleServletSetting">

                    <param1>default</param1>

                    ...

            </config>

    </interface>

    SampleServletSetting is the configuration class of SampleServlet, with param1 corresponding to the property of the SampleServletSetting class.

    In the implementation class of the service interface, InterfaceContextAware can be used to get the service interface context, through which the service components and the configuration information of the service interfaces in services interface configuration file can be got. The code is as follows:

    @Interface(componentTypes = { com.supermap.services.components.Map.class }, optional = false, multiple = false)
@Protocol(names={"SampleInterface"})
public class SampleServlet extends HttpServlet implements InterfaceContextAware {
        ...
    public void setInterfaceContext(InterfaceContext context) {
            //Get service interface configuration from the service interface context
            SampleInterfaceConfig sampleConfig = context.getConfig(SampleInterfaceConfig.class);
    }
}

    SampleInterfaceConfig object corresponds to the <config class="com.supermap.sample.SampleServletSetting"/> in the interface.

    If additional configuration is not needed for the service interface, it is not necessary to define the service interface configuration class.

    Getting service components

    SuperMap iServer publishes the service components as Web services through the corresponding service interfaces. In the implementation class of the resource, GIS capabilities of the service components obtained from the service interface context.

    @Interface(componentTypes = { com.supermap.services.components.Map.class }, optional = false, multiple = false)
@Protocol(names={"SampleInterface"})
public class SampleServlet extends HttpServlet implements InterfaceContextAware {
        ...
        public void setInterfaceContext(InterfaceContext context) {
                //Get service components from the service interface context (here it is MapComponent)
                List components = context.getComponents(Map.class);
                ...
        }
}

    Extension example

    The service interface determines how GIS capabilities are provded. By extending service interfaces, the formats in which the services are provided can be enriched, therefore better satisfying the needs of users.

    In this example, a BingMaps image output interface is implemented. You can find the sample code in %SuperMap iServer_HOME%/samples/DSSE/BingMapsInterfaceSample.

    According to the REST interface of BingMaps, we can get a map by accessing the URI below:

    http://dev.virtualearth.net/REST/v1/Imagery/Map/ Road?mapArea=30.0,100.0,50.0,120.0&mapSize=512,512&key=BingMapsKey

    "Road" is the map name provided by BingMap, mapArea (latitude top, longitude left, latitude bottom, and longitude right) is the geographical bounds for map image output, mapSize is the map image size (width, height), and BingMapsKey is the key to access BingMaps, please refer to BingMaps Key (http://msdn.microsoft.com/en-us/library/ff428642.aspx).

    Actually, the REST interface of BingMap has serveral parameters. As an demonstration, here we only adopt 3 parameters--imagerySet, mapArea, and mapSize.

    Below is the BingMapServlet implementation class, which implements the handling of URI and calling of the Map component to get the map image:

    BingMapsServlet.java

    Place the Jar package after compiling in %SuperMap iServer_HOME%\webapps\iserver\WEB-INF\lib.

    Add the BingMapsREST service interface, i.e., the <interface /> node in services.xml (refer to Structure of Service Configure File), as shown below:

    <interface class="com.supermap.sample.serviceinterface.BingMapsServlet" name="bingmapsrest">

    </interface>

    Modify the configuration for the map-world component by adding bingmapsrest to the service interfaces bound with map-world, as shown below:

    <component class="com.supermap.services.components.impl.MapImpl" interfaceNames="rest,wms111,wms130,wmts100,bingmaps"

    name="map-world" providers="ugcMapProvider-World">

            <config class="com.supermap.services.components.MapConfig">

            </config>

    </component>

    Implement the GET request on http://localhost:8090/iserver/services/map-world/bingmaps/WorldMap?mapArea=10.0,100.0,50.0,180.0&mapSize=512,512 to get the map in png format, as shown below: