java项目中通过添加filter过滤器解决ajax跨域问题

1、在web.xml添加filter

<filter>
<filter-name>contextfilter</filter-name>
<filter-class>com.cf.hr.filter.WebContextFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>contextfilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>

2、filter实现

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.HttpServletResponse;
 
public class WebContextFilter implements Filter {
 
    @Override
    public void destroy() {
        // TODO Auto-generated method stub
         
    }
 
    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        HttpServletResponse  httpServletResponse = (HttpServletResponse) response;
        httpServletResponse.setHeader("Access-Control-Allow-Origin", "*");
        httpServletResponse.setHeader("Access-Control-Allow-Headers", "accept,content-type"); 
        httpServletResponse.setHeader("Access-Control-Allow-Methods", "OPTIONS,GET,POST,DELETE,PUT"); 
        chain.doFilter(request, httpServletResponse);
         
    }
 
    @Override
    public void init(FilterConfig arg0) throws ServletException {
        // TODO Auto-generated method stub
         
    }
 
}