java SSM 解决跨域问题

1.什么是跨域请求

由于浏览器同源策略，凡是发送请求url的协议、域名、端口三者之间任意一与当前页面地址不同即为跨域。具体可以查看下表

2.解决跨域请求

1. 新建一个过滤器，并实现 Filter 接口

package hbsi.yfzx.filter;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
 * 解决SSM跨域问题
 * @author lzch
 *
 */
public class SimpleCORSFilter implements Filter {
    private boolean isCross = false;

    public void destroy() {
        isCross = false;
    }

    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        if (isCross) {
            HttpServletRequest httpServletRequest = (HttpServletRequest) request;
            HttpServletResponse httpServletResponse = (HttpServletResponse) response;
            System.out.println("拦截请求: " + httpServletRequest.getServletPath());
            httpServletResponse.setHeader("Access-Control-Allow-Origin", "*");
            httpServletResponse.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
            httpServletResponse.setHeader("Access-Control-Max-Age", "0");
            httpServletResponse.setHeader("Access-Control-Allow-Headers",
                    "Origin, No-Cache, X-Requested-With, If-Modified-Since, Pragma, Last-Modified, Cache-Control, Expires, Content-Type, X-E4M-With,userId,token");
            httpServletResponse.setHeader("Access-Control-Allow-Credentials", "true");
            httpServletResponse.setHeader("XDomainRequestAllowed", "1");
        }
        chain.doFilter(request, response);
    }

    public void init(FilterConfig filterConfig) throws ServletException {
        String isCrossStr = filterConfig.getInitParameter("IsCross");
        isCross = isCrossStr.equals("true") ? true : false;
        System.out.println(isCrossStr);
    }



}

2.在web.xml中配置

<!-- 跨域请求 -->
	<filter>
		<filter-name>SimpleCORSFilter</filter-name>
		<filter-class>hbsi.yfzx.filter.SimpleCORSFilter</filter-class>
		<init-param>
			<param-name>IsCross</param-name>
			<param-value>true</param-value>
		</init-param>
	</filter>
	<filter-mapping>
		<filter-name>SimpleCORSFilter</filter-name>
		<url-pattern>/*</url-pattern>
	</filter-mapping>

3.. 在

<!-- 接口跨域配置 -->  
      <mvc:cors>  
          <mvc:mapping path="/**"  
                       allowed-origins="*"  
                       allowed-methods="POST, GET, OPTIONS, DELETE, PUT"  
                       allowed-headers="Content-Type, Access-Control-Allow-Headers, Authorization, X-Requested-With"  
                       allow-credentials="true" />  
      </mvc:cors>  

StringMVC 的配置文件中配置跨域请求