dwr+spring3集成 .

DWR（Direct Web Remoting）是一个用于改善web页面与Java类交互的远程服务器端Ajax开源框架,可以帮助开发人员开发包含AJAX技术的网站.它可以允许在浏览器里的代码使用运行在WEB服务器上的JAVA函数,就像它就在浏览器里一样。

         

以下模拟一个简单的dwr入门案例，重点理解dwr是如何跟java后台服务器打交道的

模拟效果如下

该功能说明了dwr是怎么跟后台服务器打交道的

模拟从服务器加载下拉列表数据

模拟保存功能

模拟查询功能

                  

接下来为dwr+spring集成步骤：

1、新建一个web工程，导入dwr+spring所需jar，如下图

              

目录结构图

              

修改web.xml

<?xml version="1.0" encoding="UTF-8"?><web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"><!-- Spring上下文 --><context-param><param-name>contextConfigLocation</param-name><param-value>classpath:resource/app*.xml</param-value></context-param><listener><listener-class>org.springframework.web.context.ContextLoaderListener</listener-class></listener><!-- 配置DWR前端控制器 --><servlet><servlet-name>dwrServlet</servlet-name><servlet-class>org.directwebremoting.servlet.DwrServlet</servlet-class><!-- 指定配置文件 --><init-param><param-name>config</param-name><!-- 如果有多个用","分开 --><param-value>/WEB-INF/classes/config/dwr.xml </param-value></init-param><init-param><param-name>debug</param-name><param-value>true</param-value></init-param></servlet><servlet-mapping><servlet-name>dwrServlet</servlet-name><url-pattern>/dwr/*</url-pattern> </servlet-mapping> </web-app>

              

新建实体类Dept

package entity; publicclass Dept { private Long id; private String name; public Dept() { } public Dept(Long id, String name) { this.id = id; this.name = name; } public Long getId() { return id; } publicvoid setId(Long id) { this.id = id; } public String getName() { return name; } publicvoid setName(String name) { this.name = name; } }

            

新建业务逻辑类

 DeptServices类

package services; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import entity.Dept; @SuppressWarnings("unchecked") publicclass DeptServices { public List findDept() { thrownew RuntimeException("查找失败!"); } publicvoid deleteDept(Long id) { System.out.println("Delete dept "+ id); } public List getDeptsForPo() { List depts =new ArrayList(); depts.add(new Dept(1l, "教质部")); depts.add(new Dept(2l, "学术部")); depts.add(new Dept(3l, "就业部")); depts.add(new Dept(4l, "咨询部")); return depts; } publicvoid saveDept(List<Dept> depts) { // System.out.println(dept.getId() + ":" + dept.getName()); System.out.println(depts); } public List getDepts() { List depts =new ArrayList(); Map map =new HashMap(); map.put("id", "01"); map.put("name", "教质部"); depts.add(map); map =new HashMap(); map.put("id", "02"); map.put("name", "学术部"); depts.add(map); map =new HashMap(); map.put("id", "03"); map.put("name", "就业部"); depts.add(map); map =new HashMap(); map.put("id", "04"); map.put("name", "咨询部"); depts.add(map); try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } return depts; } }

                

HelloServices类

package services; /** * @author dlwu * */publicclass HelloServices { public String sayHello(String name){ System.out.println("Hello now!"); return"Hello "+ name +"!"; } }

             

LoginService类

package services; import org.directwebremoting.WebContext; import org.directwebremoting.WebContextFactory; publicclass LoginService { publicvoid checkUserLogin(String userid, String pwd){ WebContext ctx = WebContextFactory.get(); ctx.getSession().setAttribute("userid", userid); } public String getLoginUser(){ WebContext ctx = WebContextFactory.get(); return (String)ctx.getSession().getAttribute("userid"); } }

            

配置applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?><!-- 配置系统基础环境 --><beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd"><bean id="deptServices"class="services.DeptServices"></bean><bean id="loginSrv"class="services.LoginService"></bean></beans>

             

配置dwr.xml,dwr.xml是前台js跟java服务器沟通的桥梁

<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE dwr PUBLIC "-//GetAhead Limited//DTD Direct Web Remoting 2.0//EN""http://getahead.org/dwr/dwr20.dtd"><!-- 通用dwr配置 --><dwr><allow><!-- 建立JS对象，将目标对象的方法转换成JS对象的方法 --><create javascript="helloSrv" creator="new"><param name="class" value="services.HelloServices"></param></create><!-- 从Spring中获取Java对象 --><create javascript="deptSrv" creator="spring"><param name="beanName" value="deptServices"></param><!-- 禁止执行 --><exclude method="deleteDept"/></create><create javascript="loginSrv" creator="spring"><param name="beanName" value="loginSrv"></param></create><!-- 指定针对于特定对象的转换器 --><convert match="entity.*" converter="bean"></convert><convert match="java.lang.Throwable" converter="bean"><param name="include" value="message"></param></convert></allow></dwr>

             

页面

hello.jsp页面

<%@ page language="java"import="java.util.*" pageEncoding="UTF-8"%><% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><base href="<%=basePath%>"><title>My JSP 'hello.jsp' starting page</title><meta http-equiv="pragma" content="no-cache"><meta http-equiv="cache-control" content="no-cache"><meta http-equiv="expires" content="0"><meta http-equiv="keywords" content="keyword1,keyword2,keyword3"><meta http-equiv="description" content="This is my page"></head><!-- 记得引入js，测试地址： http://localhost:8083/dwrweb/dwr/ --><script type="text/javascript" src="dwr/engine.js"></script><script type="text/javascript" src="dwr/interface/helloSrv.js"></script><script type="text/javascript" src="dwr/util.js"></script><script type="text/javascript"> function hello(){ //方法一 //返回处理后的结果信息/*var fn = function(result){ $("msg").innerHTML = result; } helloSrv.sayHello($("name").value, fn);*///方法二 helloSrv.sayHello($("name").value, function(result){ $("msg").innerHTML=result; }); //方法三 //使用如下的好处为：不用导入如上三个js //第一个参数: dwr访问路径，在web.xml中配置，如： <url-pattern>/dwr/*</url-pattern> //第二个参数: dwr与java服务器通信变量，在dwr.xml中声明 //第三个参数: 服务器方法名 //第四个参数: 页面请求参数，即服务器方法名得参数 //第五个参数: 回调函数 //dwr.engine._execute("dwr", 'helloSrv', 'sayHello', $("name").value, fn); } </script><body><div id="msg"></div><input type="text" id="name"/><input type="button" value="Hello" onclick="hello();"/></body></html>

               

dept.jsp页面

<%@ page language="java"import="java.util.*" pageEncoding="UTF-8"%><% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html><head><base href="<%=basePath%>"><title>My JSP 'hello.jsp' starting page</title><meta http-equiv="pragma" content="no-cache"><meta http-equiv="cache-control" content="no-cache"><meta http-equiv="expires" content="0"><meta http-equiv="keywords" content="keyword1,keyword2,keyword3"><meta http-equiv="description" content="This is my page"></head><!-- 记得引入js，测试地址： http://localhost:8083/dwrweb/dwr/ --><script type="text/javascript" src="dwr/engine.js"></script><script type="text/javascript" src="dwr/interface/helloSrv.js"></script><script type="text/javascript" src="dwr/util.js"></script><script type="text/javascript"> function loadDept(){ //说明已经加载，不必重新加载if($('depts').options.length >0){ return; } DWRUtil.addOptions('depts', [{id:'',name:'正在下载...'}], 'id', 'name'); dwr.engine._execute("dwr", 'deptSrv', 'getDepts', function(depts){ DWRUtil.removeAllOptions('depts'); DWRUtil.addOptions('depts', depts, 'id', 'name'); }); } function loadDept2(){ if($('depts2').options.length >0){ return; } DWRUtil.addOptions('depts2', [{id:'',name:'正在下载...'}], 'id', 'name'); dwr.engine._execute("dwr", 'deptSrv', 'getDeptsForPo', function(depts){ DWRUtil.removeAllOptions('depts2'); DWRUtil.addOptions('depts2', depts, 'id', 'name'); }); } function saveDept(){ //声明dept对象 var dept = { id:$("deptid").value, name:$("deptname").value }; dwr.engine._execute("dwr", 'deptSrv', 'saveDept', [dept], function(){ alert('保存成功!'); }); } function find(){ dwr.engine._execute("dwr", 'deptSrv', 'findDept', { callback:function(results){ alert('查询成功!'); }, errorHandler:function(e){ alert("查询失败:"+ e); } }); } </script><body><select id="depts" onclick="loadDept();"></select><select id="depts2" onclick="loadDept2();"></select><hr/> ID:<input id="deptid" type="text" size="8"/> Name:<input id="deptname" type="text" size="8"/><input value="保存部门" type="button" onclick="saveDept();"/><input value="查找" type="button" onclick="find();"/></body></html>