首先导入项目所需要的包，如下：dwr.jar，commons-logging-1.0.4.jar，版本可以调整
1.web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://Java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.4"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<servlet>
<servlet-name>dwr-invoker</servlet-name>
<servlet-class>org.directwebremoting.servlet.DwrServlet</servlet-class>
<init-param>
<param-name>debug</param-name>
<param-value>true</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>dwr-invoker</servlet-name>
<url-pattern>/dwr/*</url-pattern>
</servlet-mapping>
</web-app>
2.DWRTest.java
package com.micro;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
@SuppressWarnings("unchecked")
public class DWRTest {
/**
* 第一个简单调用
*/
public String getStr() {
return "第一个dwr示例，调用成功";
}
/**
* 带传递参数的调用，返回String
*/
public String getInfo(String name, int age, String address) {
return "我的名字叫" + name + ",现年" + age + "岁," + "来自" + address;
}
/**
* 返回数组Array
*/
public String[] getStrArray() {
return new String[] { "one", "two", "three", "Go!" };
}
/**
* 返回集合List
*/
public List getList() {
List list = new ArrayList();
list.add("welcome");
list.add("to");
list.add("BeiJing");
return list;
}
/**
* 返回Map类型
*/
public Map getMap() {
Map map = new HashMap();
map.put("name", "周星星");
map.put("hobby", "逃课");
return map;
}
/**
* 返回二维数组类型
*/
public List getArrayList() {
List list = new ArrayList();
list.add(new String[] { "1", "2", "3" });
list.add(new String[] { "one", "two", "three", "four", "five" });
return list;
}
/**
* Exception处理
*/
public List getListTest(List list) {
try {
list.get(0);
} catch (Exception e) {
throw new NullPointerException("数据位空");
}
return list;
}
}
3.dwr.xml
<?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>
<!-- 调用不同的方法，返回不同的数据类型 -->
<create JavaScript="dwr" creator="new">
<param name="class" value="com.micro.DWRTest" />
</create>
<!-- 类型转换为JavaBean的处理 -->
<create javascript="dwrBean" creator="new" scope="request">
<param name="class" value="com.micro.UserRs" />
</create>
<convert match="com.micro.User" converter="bean">
<param name="include" value="name,pass" />
</convert>
<!-- 异常Exception的处理 ,默认情况下dwr对异常的处理就是一个弹出框提示为Error-->
<create javascript="dwrException" creator="new">
<param name="class" value="com.micro.DWRTest" />
</create>
<convert match="java.lang.NullPointerException" converter="exception" />
</allow>
</dwr>
4.mydwr.js
/**
* 无参数
*/
function invoke1(){
dwr.getStr(
function(value){
alert(value);
}
);
}
/**
* 有参数
*/
function invoke2(){
dwr.getInfo("长江七号",3,"火星",
function(value){
alert(value);
}
);
}
/**
* 返回数组
*/
function invoke3(){
dwr.getStrArray(
function(array){
var str="";
for(var i=0;i<array.length;i++){
str += array[i]+" ";
}
alert(str);
}
);
}
/**
* 返回集合（集合和数组的处理方式一样）
*/
function invoke4(){
dwr.getList(
function(list){
var str="";
for(var i=0;i<list.length;i++){
str += list[i];
}
alert(str);
}
);
}
/**
* 返回Map
*/
function invoke5(){
dwr.getMap(
//有如下两种处理方式
/*1)已知map的key*/
function(map){
alert("姓名:"+map.name+",爱好:"+map.hobby);
}
/*2).遍历的方式
function(map){
for(var key in map){
alert(key+":"+map[key]);
}
}*/
);
}
/**
* 返回数组的集合(二维数组)
*/
function invoke6(){
dwr.getArrayList(
function(arrayList){
var str="";
for(var i=0;i<arrayList.length;i++){
for(var j=0;j<arrayList[i].length;j++){
str += arrayList[i][j];
}
str+="\n\r";
}
alert(str);
}
);
}
/**
* 同步设置
*/
function invoke7(){
dwr.engine.setAsync(false);//设置同步，那么后续的方法才能按照顺序执行
invoke1();
invoke2();
}
/**
* 批处理batch（按照先后顺序执行）
*/
function invoke8(){
dwr.engine.beginBatch();
invoke1();
invoke2();
dwr.engine.endBatch();
}
5.index.jsp
<%@ page language="java" pageEncoding="UTF-8"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <script type='text/javascript' src='dwr/engine.js'></script> <script type='text/javascript' src='dwr/util.js'></script> <script type='text/javascript' src='dwr/interface/dwr.js'></script> <script type="text/javascript" src="mydwr.js"></script> </head> <body> <input type="button" value="DRW1" onclick="invoke1()" /> <br /> <input type="button" value="DRW2" onclick="invoke2()" /> <br /> <input type="button" value="DRW3" onclick="invoke3()" /> <br /> <input type="button" value="DRW4" onclick="invoke4()" /> <br /> <input type="button" value="DRW5" onclick="invoke5()" /> <br /> <input type="button" value="DRW6" onclick="invoke6()" /> <br /> <input type="button" value="DRW7" onclick="invoke7()" /> <br /> <input type="button" value="批处理测试" onclick="invoke8()" /> </body> </html>
上述，index.jsp页面就对上述各种dwr的返回类型和批处理(batch)做了处理，做了简单的测试，Ok，测试通过，下面再介绍几个页面，
对dwr其他功能的一些简单测试：
6.异常处理：exception.jsp
<%@ page language="java" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<script type='text/javascript' src='dwr/engine.js'></script>
<script type='text/javascript' src='dwr/util.js'></script>
<script type='text/javascript' src='dwr/interface/dwrException.js'></script>
<script type="text/javascript" src="mydwr.js"></script>
<script type="text/javascript">
function convert(){
var list;
dwrException.getListTest(list,
{
exceptionHandler:function(msg){
alert(msg);
},
callback:function(data){
alert(data);
}
}
);
}
</script>
</head>
<body>
<input type="button" value="异常测试" onclick="convert()"/>
</body>
</html>
7.dwr.util.getValue()调用，dwrfunc.jsp
<%@ page language="java" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<script type='text/javascript' src='dwr/engine.js'></script>
<script type='text/javascript' src='dwr/util.js'></script>
<script type='text/javascript' src='dwr/interface/dwr.js'></script>
<script type="text/javascript" src="mydwr.js"></script>
</head>
<body>
<input type="text" name="name" id="nameid" />
<br/>
<input type="button" value="EL通过id取值" onclick="alert(${'nameid'}.value)" />
<br />
//如果要是有dwr.util提供的功能，必须引入dwr/util.js文件,dwr3之后，有写函数内写name或id都可以
<br/>
<input type="button" value="dwr.util通过id" onclick="alert($('nameid').value)" />
<br />
<input type="button" value="dwr.util通过name" onclick="alert($('name').value)" />
<br />
<input type="button" value="dwr.util通过name/id" onclick="alert(dwr.util.getValue('name'))" />
<br />
</body>
</html>
8.对JavaBean的传递和返回
User.java:
package com.micro;
public class User {
private String name;;
private String pass;
//get/set方法....
}
UserRs.java:
package com.micro;
public class UserRs {
public User convertUser(User user) {
user.setName("admin");
user.setPass("123456");
return user;
}
}
bean.jsp:
<%@ page language="java" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<script type='text/javascript' src='dwr/engine.js'></script>
<script type='text/javascript' src='dwr/util.js'></script>
<script type='text/javascript' src='dwr/interface/dwrBean.js'></script>
<script type="text/javascript" src="mydwr.js"></script>
<script type="text/javascript">
function convert(){
var uname = $("name").value;
var upass = $("pass").value;
var obj = {name:uname,pass:upass};
dwrBean.convertUser(obj,function(data){
$("uname").value = data.name;
$("upass").value = data.pass;
});
}
</script>
</head>
<body>
<input type="text" name="name" id="uname" value="you name"/><br/>
<input type="text" name="pass" id="upass" value="your password"/><br/>
<input type="button" value="测试处理" onclick="convert()"/>
</body>
</html>
这些，只是对dwr的简单应用，其中的配置都在dwr.xml中，大家可以举一反三，通常情况下，dwr和spring要结合使用，下面给出一个简单的配置说明：
比如：
<!-- 验证登陆名是否存在 -->
<create creator="spring" javascript="loginServiceDWR" scope="request">
<param name="beanName" value="coreLoginService" />
<include method="checkLogin" />
</create>
其中，creator="spring"，表明由spring来创建该对象，javascript="loginServiceDWR"，说明客户端的调用名称叫"loginServiceDWR"，<param name="beanName" value="coreLoginService" />指明了spring配置文件中，id为"coreLoginService"的这么一个bean，<include method="checkLogin" />，对外公开的方法是"checkLogin" ，调用过程同上述其他类型调用相同，不同就是配置而已。上述代码，仅供参考。
注意：引入dwr的js文件的顺序不能错了，如：
<script type='text/javascript' src='dwr/engine.js'></script>
<script type='text/javascript' src='dwr/util.js'></script>
<script type='text/javascript' src='dwr/interface/dwrBean.js'></script>
先引入dwr自身的，再引入自己的。