java后端解决跨域问题

1.新建一个filter

public class CORSFilter extends Filter {

/**
 * 跨域处理
 * 
 * @param request
 * @param response
 * @param filterChain
 * @throws ServletException
 * @throws IOException
 */
@Override
protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
throws ServletException, IOException {

response.addHeader("Access-Control-Allow-Origin", "*");
if (request.getHeader("Access-Control-Request-Method") != null && "OPTIONS".equals(request.getMethod())) {
response.addHeader("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE");
response.addHeader("Access-Control-Allow-Headers", "Content-Type");
response.addHeader("Access-Control-Max-Age", "1");
}

filterChain.doFilter(request, response);
}
}

2.另外web.xml中新增配置

<filter>
<filter-name>CORS</filter-name>
<filter-class>com.ymerp.support.CORSFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>CORS</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>