DWR框架入门例子

关于dwr的概念，摘自百度百科：

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。

DWR框架使用之一：单独使用

步骤：

1、在pom.xml中配置依赖。（就是加载jar包）

2、在web.xml中配置servlet。

3、写一个普通java类。

4、配置dwr.xml文件，配置要公开的类或方法。

5、写一个jsp页面，主要导入engine.js和相应的java类映射的js文件，然后编写js即可调用。

详细：

1、pom.xml代码如下：

[html] view plain copy <?xml version="1.0" encoding="UTF-8"?>  <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">      <modelVersion>4.0.0</modelVersion>        <groupId>com.lessony</groupId>      <artifactId>dwr01</artifactId>      <version>1.0-SNAPSHOT</version>      <packaging>war</packaging>        <name>dwr01</name>        <properties>          <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>      </properties>            <dependencies>          <!--DWR的jar包-->          <dependency>              <groupId>org.directwebremoting</groupId>              <artifactId>dwr</artifactId>              <version>3.0.M1</version>          </dependency>                    <!--由于使用jetty来运行web,jetty日志输出需要日志jar包，可以使用common-logging的日志框架-->          <!--          <dependency>                  <groupId>commons-logging</groupId>                  <artifactId>commons-logging</artifactId>                  <version>1.2</version>          </dependency>          -->                    <!--slf4j日志框架，jcl-over-slf4j是将common-logging的日志调用到slf4j，maven会把其它依赖包导入-->          <dependency>              <groupId>org.slf4j</groupId>              <artifactId>jcl-over-slf4j</artifactId>              <version>1.7.6</version>          </dependency>      </dependencies>        <build>          <plugins>              <plugin>                  <groupId>org.mortbay.jetty</groupId>                  <artifactId>jetty-maven-plugin</artifactId>                  <version>8.1.16.v20140903</version>                  <configuration>                          <scanIntervalSeconds>10</scanIntervalSeconds>                          <webApp>                                  <contextPath>/dwr01</contextPath>                          </webApp>                          <connectors>                                  <connector implementation="org.eclipse.jetty.server.nio.SelectChannelConnector">                                          <port>8888</port>                                          <maxIdleTime>60000</maxIdleTime>                                  </connector>                          </connectors>                  </configuration>              </plugin>                            <!--打包插件，把web打成zip包-->              <plugin>                  <groupId>org.apache.maven.plugins</groupId>                  <artifactId>maven-assembly-plugin</artifactId>                  <version>2.4</version>                  <configuration>                      <descriptors>                          <descriptor>assembly.xml</descriptor>                      </descriptors>                  </configuration>                  <executions>                      <!-- 当执行mvn package时才会打包 -->                      <execution>                          <id>make-assembly</id>                          <phase>package</phase>                          <goals>                              <goal>single</goal>                          </goals>                      </execution>                  </executions>              </plugin>          </plugins>      </build>    </project>  

2、配置web.xml [html] view plain copy <?xml version="1.0" encoding="UTF-8"?>  <web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.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>  

3、写一个普通的java类

[java] view plain copy package com.lessony.dwr01;    /**  *  * @author Lessony  */  public class Hello {      public String sayHello(String name){          System.out.println("hello "+name);          return "hello "+name;      }  }   4、配置dwr.xml [html] view plain copy <?xml version="1.0" encoding="UTF-8"?>  <!DOCTYPE dwr PUBLIC "-//GetAhead Limited//DTD Direct Web Remoting 3.0//EN" "http://getahead.org/dwr/dwr30.dtd">    <dwr>      <allow>            <create creator="new">                <param name="class" value="com.lessony.dwr01.Hello"/>            </create>       </allow>  </dwr>  

5、jsp文件 [html] view plain copy <%@page contentType="text/html" pageEncoding="UTF-8"%>  <!DOCTYPE html>  <html>      <head>          <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">          <title>JSP Page</title>          <script src="<%=request.getContextPath()%>/dwr/engine.js"></script>          <script src="<%=request.getContextPath()%>/dwr/interface/Hello.js"></script>                    <script>              Hello.sayHello("张三");          </script>      </head>      <body>          <h1>Hello World!</h1>      </body>  </html>  

全部编辑完成之后，打开浏览器，输入http://localhost:8888/dwr01/dwr01.jsp，就可以看到控制台输出了：hello 张三

最后附上zip包，链接：http://download.csdn.net/detail/lxn39830435731415926/8708077