关于Java跨域的总结

• 使用crossdomain.xml 文件实现跨域(flex)
• 配置filter过滤器
• 配置springMVC

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* 1. 首先使用用crossdomain.xml文件实现跨域 *

<?xml version="1.0"?>    <cross-domain-policy>    <allow-access-from domain="localhost:8080" />   </cross-domain-policy>  

表示允许来源为本地8080端口的请求，因为Tomcat默认是访问的webapp下面的root目录，所以要将这个文件放到该目录下。。

* 2. 使用过滤器实现 *

<filter>        <display-name>AcrossDomainFilter</display-name>        <filter-name>AcrossDomainFilter</filter-name>        <filter-class>com.test.demo.filter.AcrossDomainFilter</filter-class>    </filter>    <filter-mapping>        <filter-name>AcrossDomainFilter</filter-name>        <url-pattern>/*</url-pattern>    </filter-mapping> 

Java代码为：

    /**     * @see Filter#doFilter(ServletRequest, ServletResponse, FilterChain)     * 配置跨域过滤器     *      */    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {        HttpServletRequest httpRequest = (HttpServletRequest) request;        HttpServletResponse httpResponse = (HttpServletResponse) response;        httpResponse.addHeader("Access-Control-Allow-Origin", "*");        httpResponse.addHeader("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE");        httpResponse.addHeader("Access-Control-Allow-Headers", "Content-Type");        httpResponse.addHeader("Access-Control-Max-Age", "1800");//30 min        chain.doFilter(httpRequest, httpResponse);    }

* 3. 使用springMVC配置文件 *

 <mvc:cors>        <mvc:mapping path="/**" allowed-origins="*" allow-credentials="true" max-age="1800" allowed-methods="GET,POST,OPTIONS"/>    </mvc:cors>

因为使用了springMVC 所以也可以利用它来配置跨域。因为这个项目前端是跑在node里面，所以开发的时候不得已需要跨域。