Java 后端彻底解决跨域问题（CORS）

接口调用出现跨域问题时，浏览器会报如下提示

XMLHttpRequest cannot load xxx. Request header field Authorization is not allowed by Access-Control-Allow-Headers in preflight response.

等等信息

直接通过一个过滤器来解决

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;

import org.apache.log4j.Logger;
import org.springframework.stereotype.Component;

/**
 * 允许跨域过滤器(Cross-Origin Resource Sharing)
 * @author user
 *
 */
@Component
public class CorsFilter implements Filter {

    private final Logger logger = Logger.getLogger(this.getClass().getPackage().getName());

    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
        HttpServletResponse response = (HttpServletResponse) res;  

        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Allow-Credentials", "true");
        response.setHeader("Access-Control-Allow-Methods", "*");
        response.setHeader("Access-Control-Max-Age", "3600");
//        response.setHeader("Access-Control-Allow-Headers", "*");
        response.setHeader("Access-Control-Allow-Headers", "Authorization,Origin,X-Requested-With,Content-Type,Accept,"
                + "content-Type,origin,x-requested-with,content-type,accept,authorization,token,id,X-Custom-Header,X-Cookie,Connection,User-Agent,Cookie,*");
        response.setHeader("Access-Control-Request-Headers", "Authorization,Origin, X-Requested-With,content-Type,Accept");
        response.setHeader("Access-Control-Expose-Headers", "*");

        chain.doFilter(req, response);
    }

    public void init(FilterConfig filterConfig) {}

    public void destroy() {}

}

web.xml 文件

<!-- 跨域过滤器 -->
<filter>
    <filter-name>corsFilter</filter-name>
    <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>
<filter-mapping>
    <filter-name>corsFilter</filter-name>
    <url-pattern>/dental/*</url-pattern>
</filter-mapping>
<filter-mapping>
    <filter-name>corsFilter</filter-name>
    <url-pattern>/toothCheck/*</url-pattern>
</filter-mapping>

原文地址：

https://www.cnblogs.com/poterliu/p/11339942.html