cors实现跨域请求

先贴出几个关于跨域的介绍和解决办法的链接：
详解js跨域问题
跨域问题：解决跨域的三种方案
服务器端解决跨域问题的三种方法
利用CORS实现跨域请求
这里记录一个CORS实现跨域的实操(针对web项目)：
1.在pom文件中添加依赖：

        <dependency>            <groupId>org.mortbay.jetty</groupId>            <artifactId>jsp-2.1</artifactId>            <version>6.0.0</version>            <scope>runtime</scope>        </dependency>

2.在web.xml文件中添加以下配置:

<!-- 跨域访问 -->    <filter>           <filter-name>CORS</filter-name>          <filter-class>com.thetransactioncompany.cors.CORSFilter</filter-class>          <init-param>              <param-name>cors.allowOrigin</param-name>              <param-value>*</param-value>          </init-param>          <init-param>              <param-name>cors.supportedMethods</param-name>              <param-value>GET, POST, HEAD, PUT, DELETE,OPTION</param-value>          </init-param>          <init-param>              <param-name>cors.supportedHeaders</param-name>              <param-value>Accept, Origin, X-Requested-With, Content-Type, Last-Modified</param-value>          </init-param>          <init-param>              <param-name>cors.exposedHeaders</param-name>              <param-value>Set-Cookie</param-value>          </init-param>          <init-param>              <param-name>cors.supportsCredentials</param-name>              <param-value>true</param-value>          </init-param>          <init-param>              <param-name>cors.maxAge</param-name>              <param-value>3600</param-value>          </init-param>    </filter>    <filter-mapping>          <filter-name>CORS</filter-name>          <url-pattern>/*</url-pattern>    </filter-mapping>