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; 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 " > </ 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 >