dwr+spring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; public class 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; } public void setId(Long id) { this.id = id; } public String getName() { return name; } public void 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") public class DeptServices { public List findDept() { throw new RuntimeException("查找失败!"); } public void 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; } public void 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 * */ public class 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; public class LoginService { public void 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">