1.官网下载 http://directwebremoting.org/dwr/downloads/index.html#stableReleasedwr.jar的java包
http://commons.apache.org/proper/commons-logging/下载 Commons Logging.,因为dwr依赖日志jar包
并将dwr.jar和commons-logging-1.1.3.jar添加到web工程的lib下面
<servlet> <display-name>DWR Servlet</display-name> <servlet-name>dwr-invoker</servlet-name> <servlet-class>org.directwebremoting.servlet.DwrServlet</servlet-class> <init-param> <param-name>crossDomainSessionSecurity</param-name> <param-value>false</param-value> </init-param> </servlet> <servlet-mapping> <servlet-name>dwr-invoker</servlet-name> <url-pattern>/dwr/*</url-pattern> </servlet-mapping>
在init-param中有一个属性为crossDomainSessionSecurity,默认为true,设为false的原因在于dwr采用的request使用了秘密的请求,为了防止csrf攻击,详情参看官网描述
http://directwebremoting.org/dwr/security/script-tag-protection.html#scriptTagHack
3.在WEB-INF下面新建dwr的配置文件dwr.xml 内容如下
<?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"> <dwr> <allow> <create creator="new" javascript="DWRTestJava"> <param name="class" value="com.undergrowth.dwrtest.DWRTest" /> </create> <convert converter="bean" match="com.undergrowth.bean.Person" /> </allow> <signatures> <![CDATA[ import java.util.List; import java.util.Map; ]]> </signatures> </dwr>
在这里稍微注意一下 在官网上头部为
<!DOCTYPE dwr PUBLIC "-//GetAhead Limited//DTD Direct Web Remoting 3.0//EN" "http://getahead.org/dwr/dwr30.dtd">
这里改成如上 2.0 20因为 我们使用的dwr版本为2.0.10 不然会造成版本不匹配的问题
对于dwr.xml的配置文件里面的涵义分别如下:
create标签主要负责用于声明公开给javascript调用的类和方法
如果在create标签里面没有指明公开的方法的话 默认公开所有方法
convert标签指明了参数传递和返回值时,对应的javabean应该如何映射,对于java基本的数据类型还有数组、列表的话 dwr会自动在javascript和java类型之间转换(意思就是,如果在参数传递和返回值的时候没有javabean的话,可以不用convert标签)
4.编写java端代码,如下
DWRTest.java
package com.undergrowth.dwrtest; import java.util.ArrayList; import java.util.Date; import java.util.HashMap; import java.util.List; import java.util.Map; import com.undergrowth.bean.Person; public class DWRTest { public DWRTest(){} //传入参数 返回值 public String dwrReturnString(String name) { return "你的姓名为:"+name; } //传入参数 返回列表 public List<Person> dwrReturnList(String name) { Person person=new Person(name,new Date(),20); List<Person> list=new ArrayList<>(); list.add(person); return list; } //传入参数 返回列表 public Map<String,Person> dwrReturnMap(String name) { Person person=new Person(name,22); Map<String,Person> map=new HashMap<>(); map.put("1",person); return map; } //传入JavaBean 返回JavaBean public Person dwrReturnBean(Person p) { Person person=new Person(p.getName(),p.getAge()); return person; } }
Person.java
package com.undergrowth.bean; import java.util.Date; public class Person { private String name; public String getName() { return name; } public void setName(String name) { this.name = name; } public Date getBirthday() { return birthday; } public void setBirthday(Date birthday) { this.birthday = birthday; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } private Date birthday; private int age; public Person(String name,Date birthday,int age) { super(); this.name = name; this.birthday = birthday; this.age = age; } public Person() { super(); } }
5.测试首页 index.jsp
<%@ page language="java" import="java.util.*" pageEncoding="gbk"%> <% 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 'index.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"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> <script type="text/javascript" src="<%=basePath%>/dwr/interface/DWRTestJava.js"></script> <script type="text/javascript" src="<%=basePath%>/dwr/engine.js" ></script> <script type="text/javascript" src="<%=basePath%>/dwr/util.js" ></script> <script type="text/javascript"> window.onload=init; function init() { document.getElementById("startId").innerHTML="开始dwr调用,路径为:<%=basePath%>"; //调用返回字符串函数 DWRTestJava.dwrReturnString("张三",callReturnFunc); //调用返回列表函数 DWRTestJava.dwrReturnList("张三",callReturnFuncList); //调用返回map函数 DWRTestJava.dwrReturnMap("张三",callReturnFuncMap); //传入javabean进行处理 再返回javabean var infoVo={ name:"张三",age:100 }; DWRTestJava.dwrReturnBean(infoVo,callReturnFuncBean); } function callReturnFunc(data) { //document.getElementById("startId").innerHTML="开始dwr字符串调用调用"; document.getElementById("contentId").innerHTML=data; } function callReturnFuncList(list) { var data="list总共有:"+list.length+"个元素,"; for(var i=0;i<list.length;i++) { var person=list[i]; data+=person.name+" "+person.birthday+" "+person.age+"\n"; } document.getElementById("contentListId").innerHTML=data; } function callReturnFuncMap(map) { var count=0; var data=""; for(var i in map) { var person=map[i]; data+=person.name+" "+person.birthday+" "+person.age+"\n"; count++; } document.getElementById("contentMapId").innerHTML="map总共有:"+count+"个元素,"+data; } function callReturnFuncBean(data) { document.getElementById("contentVoId").innerHTML=data.name+" "+data.birthday+" "+data.age; } </script> </head> <body> <span id="startId"></span><br/> <span id="contentId"></span><br/> <span id="contentListId"></span><br/> <span id="contentMapId"></span><br/> <span id="contentVoId"></span><br/> </body> </html>
6.结果
http://localhost:8080/DwrTest1/index.jsp
如下