JAVA ADF 运行原理(5)

Fuctionality全称为GISFunctionality,每个GISResource对应多个GISFunctionality，

由Fuctionality来提供实际功能，我们通过ADF模板生成一个完整的工程，在WEB-INF/functionalities目录下可以看到多个functionality，这些funtionalities将会被注册到web.xml配置文件中，如下：

<context-param>
<param-name>javax.faces.CONFIG_FILES</param-name>
<param-value>
/WEB-INF/functionalities/aims-functionalities.xml,
/WEB-INF/functionalities/ags-functionalities.xml,
/WEB-INF/functionalities/aws-functionalities.xml,
/WEB-INF/functionalities/wms-functionalities.xml,
/WEB-INF/functionalities/ejb-functionalities.xml,
/WEB-INF/functionalities/graphics-functionalities.xml,
/WEB-INF/ajax-renderers.xml,
/WEB-INF/context-attributes.xml
</param-value>
</context-param>

其中ags-functionalities.xml,定义了关于GISResource功能的配置信息，文件中定义了多个操作GISResource的基本Functionality，下面给出部分配置信息：

<?xml version="1.0"?>
<!DOCTYPE faces-config PUBLIC "-//Sun Microsystems, Inc.//DTD JavaServer Faces Config 1.0//EN" "http://java.sun.com/dtd/web-facesconfig_1_0.dtd">
<faces-config>
<managed-bean>
<managed-bean-name>agsMap</managed-bean-name>
<managed-bean-class>com.esri.adf.web.ags.data.AGSMapFunctionality</managed-bean-class>
<managed-bean-scope>none</managed-bean-scope>
</managed-bean>

<managed-bean>
<managed-bean-name>agsGeocode</managed-bean-name>
<managed-bean-class>com.esri.adf.web.ags.data.AGSGeocodeFunctionality</managed-bean-class>
<managed-bean-scope>none</managed-bean-scope>
</managed-bean>

</faces-config>

我们一直再说，每个GISResource对应多个GISFunctionality，但是到目前为止，还没看到他们之间有任何关联的痕迹，那么GISResource是如何使用GISFunctionality的呢？

在faces-config.xml文件中，可以看到如下的配置信息：

<managed-bean>
<managed-bean-name>ags1</managed-bean-name>
<managed-bean-class>com.esri.adf.web.ags.data.AGSLocalMapResource</managed-bean-class>
<managed-bean-scope>none</managed-bean-scope>
<managed-property>
<property-name>user</property-name>
<value>#{agsUser1}</value>
</managed-property>
<managed-property>
<property-name>alias</property-name>
<value>shanghai</value>
</managed-property>
<managed-property>
<property-name>serverObjectName</property-name>
<value>shanghai</value>
</managed-property>
<managed-property>
<property-name>hosts</property-name>
<list-entries>
<value>localhost</value>
</list-entries>
</managed-property>
<managed-property>
<property-name>functionalities</property-name>
<map-entries>
<map-entry>
<key>map</key>
<value>#{agsMap}</value>
</map-entry>
<map-entry>
<key>query</key>
<value>#{agsQuery}</value>
</map-entry>
<map-entry>
<key>tile</key>
<value>#{agsTile}</value>
</map-entry>
<map-entry>
<key>overview</key>
<value>#{agsOverview}</value>
</map-entry>
<map-entry>
<key>toc</key>
<value>#{agsToc}</value>
</map-entry>
</map-entries>
</managed-property>
</managed-bean>
<managed-bean>
<managed-bean-name>renderer_symbol1</managed-bean-name>
<managed-bean-class>com.esri.adf.web.data.symbol.WebPictureMarkerSymbol</managed-bean-class>
<managed-bean-scope>none</managed-bean-scope>
<managed-property>
<property-name>fileName</property-name>
<value>images/maptips/pin-bl-green-20x20.png</value>
</managed-property>
</managed-bean>
<managed-bean>
<managed-bean-name>renderer1</managed-bean-name>
<managed-bean-class>com.esri.adf.web.data.renderer.WebSimpleRenderer</managed-bean-class>
<managed-bean-scope>none</managed-bean-scope>
<managed-property>
<property-name>symbol</property-name>
<value>#{renderer_symbol1}</value>
</managed-property>
</managed-bean>
<managed-bean>
<managed-bean-name>renderer_symbol2</managed-bean-name>
<managed-bean-class>com.esri.adf.web.data.symbol.WebPictureMarkerSymbol</managed-bean-class>
<managed-bean-scope>none</managed-bean-scope>
<managed-property>
<property-name>fileName</property-name>
<value>images/maptips/pin-bl-red-20x20.png</value>
</managed-property>
</managed-bean>
<managed-bean>
<managed-bean-name>renderer2</managed-bean-name>
<managed-bean-class>com.esri.adf.web.data.renderer.WebSimpleRenderer</managed-bean-class>
<managed-bean-scope>none</managed-bean-scope>
<managed-property>
<property-name>symbol</property-name>
<value>#{renderer_symbol2}</value>
</managed-property>
</managed-bean>
<managed-bean>
<managed-bean-name>layer1</managed-bean-name>
<managed-bean-class>com.esri.adf.web.data.query.LayerDefinition</managed-bean-class>
<managed-bean-scope>none</managed-bean-scope>
<managed-property>
<property-name>resourceId</property-name>
<value>ags1</value>
</managed-property>
<managed-property>
<property-name>layerId</property-name>
<value>0</value>
</managed-property>
<managed-property>
<property-name>calloutTemplate</property-name>
<value>default</value>
</managed-property>
<managed-property>
<property-name>resultTemplate</property-name>
<value>default</value>
</managed-property>
<managed-property>
<property-name>renderer</property-name>
<value>#{renderer1}</value>
</managed-property>
<managed-property>
<property-name>highlightRenderer</property-name>
<value>#{renderer2}</value>
</managed-property>
</managed-bean>
<managed-bean>
<managed-bean-name>webappQuery</managed-bean-name>
<managed-bean-class>com.esri.adf.web.data.query.WebQuery</managed-bean-class>
<managed-bean-scope>none</managed-bean-scope>
<managed-property>
<property-name>layerDefinitions</property-name>
<list-entries>
<value>#{layer1}</value>
<value>#{layer2}</value>
<value>#{layer3}</value>
<value>#{layer4}</value>
<value>#{layer5}</value>
</list-entries>
</managed-property>
</managed-bean>

看了上面的信息有何感受？

------------他妈妈的真长！

呵呵，没关系，eclipse会帮助我们完成。上面就是关于一个GISResource的配置信息，如果你只对Funtionality感兴趣，那么只需看黑体信息即可，可以看到黑体部分正是在ags-functionalities.xml中定义的 managed-bean-name，我们只需将Bean的name注册到GISResource，该GISResource即具备了该Funtionality的使用权。

通过GISFunctionality这个接口，我们可以看的更清楚.

public abstract interface GISFunctionality{

public abstract void initFunctionality(GISResource paramGISResource);

public abstract void destroyFunctionality();

public abstract GISResource getResource();

}

在GISResource被初始化的时候，ADF会遍历其所有的GISFunctionality对象并调用其initFunctionality方法，这样返回Functionality就可以被使用了。从这以后，你不但可以从GISResource获得GISFunctionality，也可以从GISFuctionality获得其GISResource。这些都是ADF在后台自动完成的工作。

当我们自定义Functionality来拓展GISResource的功能时，即采用上面的配置方式，这样我们就可以集中经历去编写自定义的Fuctionality类。下面是一个自定义放大地图5倍的Functionality，摘自arcgis server java adf，如下：

public class Zoom5Functionality implements GISFunctionality{

private GISResource resource;

public void zoomIn5(){

WebContext webContext = resource.getWebContext();

webContext.getWebMap().getCurrentExtent().expand(0.2);

webContext.refresh();

}

public void zoomOut5() {

WebContext webContext = resource.getWebContext();

webContext.getWebMap().getCurrentExtent().expand(5);

webContext.refresh();

}

public void initFunctionality(GISResource resource){

this.resource = resource;

}

public void destroyFunctionality() {}

public GISResource getResource() {

return this.resource;

}

}

public class ZoomInListener implements ActionListener{

public void processAction(ActionEvent event) throws AbortProcessingException {

WebContext webContext = WebUtil.getWebContext(event.getComponent());

GISResource resource = webContext.getResourceById("ags1");

Zoom5Functionality functionality = (Zoom5Functionality)resource.getFunctionality("zoom5Functionality");

functionality.zoomIn5();

}

}

前台调用：

<a:command id="zoomIn"

defaultImage="images/tasks/maptools/zoomin.png"

hoverImage="images/tasks/maptools/zoominU.png"

selectedImage="images/tasks/maptools/zoominD.png"

clientPostBack="true" >

<f:actionListener type="wuyf.ZoomInListener"/>

</a:command>

zoom5Functionality即为注册的Fuctionality，ZoomInListener中黑体部分实现了获取资源并调用其zoom5Functionality方法放大地图5倍的功能。