spring+javaWeb框架处理请求跨域的问题

1. 添加CorsFilterConfig实现Filter接口

@Order(1)
@Configuration
public class CorsFilterConfig implements Filter{

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        HttpServletResponse httpResponse = (HttpServletResponse) response;
        HttpServletRequest httpRequest = (HttpServletRequest) request;

        // 打印初始响应头
        System.out.println("Before setting headers: " + httpResponse.getHeaderNames());

        // 允许的源列表
        List<String> allowedOrigins = Arrays.asList(
                "http://localhost:8000",
                "http://xx.xxx.xx.xxx:8000"
        );

        // 获取请求中的 Origin
        String originHeader = httpRequest.getHeader("Origin");

        // 检查请求的 Origin 是否在允许的列表中
        if (originHeader != null && allowedOrigins.contains(originHeader)) {
            httpResponse.setHeader("Access-Control-Allow-Origin", originHeader);
            httpResponse.setHeader("Access-Control-Allow-Credentials", "true");
        }

        // 设置 CORS 响应头
        httpResponse.setHeader("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS");
        httpResponse.setHeader("Access-Control-Allow-Headers", "*");
        httpResponse.setHeader("Access-Control-Max-Age", "3600");

        // 打印最终响应头
        System.out.println("After setting headers: " + httpResponse.getHeaderNames());

        if ("OPTIONS".equalsIgnoreCase(((HttpServletRequest) request).getMethod())) {
            httpResponse.setStatus(HttpServletResponse.SC_OK);
            return;
        }

        chain.doFilter(request, response);
    }

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        System.out.println("CorsFilter initialized");
    }

    @Override
    public void destroy() {
        System.out.println("CorsFilter destroyed");
    }

}

2.在web.xml文件中将自定义的 CorsFilterConfig 类作为过滤器启用，并映射到所有请求路径 /*，这表示该过滤器会对所有请求生效。

<!-- 跨域请求过滤器 -->
<filter>
    <filter-name>corsFilter</filter-name>
    <filter-class>com.alibaba.aone.blast.webapp.config.CorsFilterConfig</filter-class>
</filter>

<filter-mapping>
    <filter-name>corsFilter</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>