jabsorb学习

jabsorb是一种基于Ajax/Web2.0的简单轻便的框架，可用于在Web浏览中通过HTTP请求向服务端发送请求，并获得响应数据。

 

1.jabsorb的安装

引用:jabsorb-1.2.2.jar，slf4j-api-1.4.2.jar，slf4j-jdk14-1.4.2.jar，jsonrpc.js

 

2.配置web.xml


<servlet>
    <servlet-name>JSONRPCServlet</servlet-name>
    <servlet-class>org.jabsorb.JSONRPCServlet</servlet-class>
   
    <init-param>
      <param-name>gzip_threshold</param-name>
      <param-value>0</param-value>
    </init-param>
  </servlet>
  <servlet-mapping>
    <servlet-name>JSONRPCServlet</servlet-name>
    <url-pattern>/JSON-RPC</url-pattern>
  </servlet-mapping>

解释一下:

这段代码配置了一个jabsorb引擎，实际上就是一个Servlet（和Struts1.x类似，也是通过Servlet作为入口的）。其中gzip_threshold可以取-1、0和一个正整数。如果值为-1，表示不会对响应的内容进行压缩，如果为0，表示对响应的所有内容进行压缩，如果为一个正整数，表示当响应内容超过这个整数时,进行压缩

 

3.开始第一个json-rpc程序:

3.1配置文件web.xml:

 

<servlet>
		<servlet-name>JSONRPCServlet</servlet-name>
		<servlet-class>org.jabsorb.JSONRPCServlet</servlet-class>

		<init-param>
			<param-name>gzip_threshold</param-name>
			<param-value>0</param-value>
		</init-param>
	</servlet>
	<servlet-mapping>
		<servlet-name>JSONRPCServlet</servlet-name>
		<url-pattern>/JSON-RPC</url-pattern>
	</servlet-mapping>

	<listener>
		<listener-class>
			test.listener.AlexSessionListener
		</listener-class>
	</listener>

 

3.2 第一个bean:

 

public class TestJabsorb implements Serializable {

	private static final long serialVersionUID = 1L;

	public String getMessage(String s) {
		return "你好：" + s;
	}

	public String getMessage() {
		return "没有值;
	}

	public String getMessage(List al) {
		String res = "list参数 ：";
		for (Iterator it = al.iterator(); it.hasNext();) {
			Object next = it.next();
			res += next + ",";
		}
		return res;
	}

	public String getMessage(String[] array) {
		String res = "数组：";
		for (int i = 0; i < array.length; i++) {
			res += array[i] + ",";
		}
		return res;
	}

	public String getMessage(Map map) {
		String res = "map参数：“;
		Set entrySet = map.entrySet();
		for (Iterator it = entrySet.iterator(); it.hasNext();) {
			Object next = it.next();
			res += next + ",";
		}
		return res;
	}

	public String getMessage(Test2 t2) {
		String res = "Test2(bean)参数 ：“;
		res += t2.p1 + ",";
		res += t2.p2 + ",";
		return res;
	}

	public Test2 getMessage2() {
		Test2 res = new Test2();
		res.p1 = "11";
		res.p2 = "22";
		return res;
	}

	public List getList() {
		List list = new LinkedList();
		list.add("中国");
		list.add(new Integer(1234));
		return list;
	}

	public Map getMap() {
		Map map = new HashMap();
		map.put("bird", "鸟);
		map.put("human", "人类");
		return map;
	}
}

 

3.3 index.jsp:

在<head>部分加入

 

<script type="text/javascript" src="script/jsonrpc.min.js"></script>

 

正文:

 

<script type="text/javascript">
   try
   {
       jsonrpc = new JSONRpcClient("JSON-RPC");
       var result = jsonrpc.alex.getMessage("alex");
       alert(result);
       result = jsonrpc.alex.getMessage();
       alert(result);
       //list parameter
       result = jsonrpc.alex.getMessage({"javaClass":"java.util.ArrayList",'list':['h1','h2','h3']}); 
       alert(result);
       //bean parameter
       result = jsonrpc.alex.getMessage({'javaClass':"test.Test2",p1:11,p2:22});
       alert(result);
       //bean return value
       result = jsonrpc.alex.getMessage2();
       alert(result.p1+'_'+result.p2);
       //list return
       result = jsonrpc.alex.getList().list;
       alert(result.length);
       //map return 
       result = jsonrpc.alex.getMap().map;
       alert(result["bird"]);
       alert(result["human"]);
       
       //asynchronized call
       function callback(result,exception){ 
		        	if(exception==null){ 
		            	alert(result);
		        	} 
            } 
       
       result = jsonrpc.alex.getMessage(callback, "vicky");
       alert(result);
    }
   catch(e)
   {
     alert(e);
   }
</script>

 

 

3.4session listener:

 

public class AlexSessionListener implements HttpSessionListener {

	public void sessionCreated(HttpSessionEvent event) {
		HttpSession session = event.getSession();
		JSONRPCBridge bridge = (JSONRPCBridge) session
				.getAttribute("JSONRPCBridge");
		if (bridge == null) {
			bridge = new JSONRPCBridge();
			session.setAttribute("JSONRPCBridge", bridge);
		}

		bridge.registerObject("alex", new TestJabsorb());
	}

	public void sessionDestroyed(HttpSessionEvent arg0) {
		// TODO Auto-generated method stub

	}

}

 

 

 

一些注意项:
1. 由于json对象注册是在session级别上注册的, 所以, 最好写一个HttpSessionListener
2. 至于session销毁的时候是否需要反注册, 待考虑
3. 默认都是同步调用的, 为了在网络环境不畅的环境下Web程序仍然能运行良好，这就需要进行异步调用。回调函数必须有两个参数，第一个参数表示返回值，第二个参数表示异常信息。如果无异常信息，第二个参数值为null。一个回调函数sample:
function callback(result,exception){
    if(exception==null){
        alert(result);
    }      
}


源码

 


posted on 2010-12-15 23:37  菊次郎  阅读(365)  评论(0)    收藏  举报