java自定义request对象，修改请求方式

刺骨的言语ヽ痛彻心扉 2023-02-18 12:52 19阅读 0赞

修改post请求参数的请参照我的[https://blog.csdn.net/qq\_34468174/article/details/106665093][https_blog.csdn.net_qq_34468174_article_details_106665093]，两者进行整合也许可以实现你需要的功能，比如根据不同请求方式、请求头分别采用不同逻辑处理请求参数！

1.场景：将前端请求的post请求全部改为 application/json的请求方式，因为有后端项目使用的是@RequestBody注解，作为中间件，需要将（其他服务）转发过来的请求更改为 application/json，控制层正常接收。

2.实现过程：研究request请求源码得出

3.实现代码

自定义request对象：

/**
     * bodyReader包装request,对宝物基座的数据进行处理,宝物基座不支持json，若需要只需要简单实现即可
     *
     * @author qiaofeng
     */
    @Slf4j
    public class BodyHttpServletRequestWrapper extends HttpServletRequestWrapper {
    
    
        private final String contentType = "application/json";
    
        private Map<String, String> headerMap = new HashMap<>();
    
        @Nullable
        private ServletInputStream body;
    
        public BodyHttpServletRequestWrapper(HttpServletRequest request) {
            super(request);
            setHeaderMap(request);
    //此处可以对数据做任何修改后，再放入到body
            String dataInfo = request.getParameter("data");
            if (StringUtils.isEmpty(dataInfo)) {
                return;
            }
            ByteArrayInputStream delegate = new ByteArrayInputStream(dataInfo.getBytes(StandardCharsets.UTF_8));
            body = new ServletInputStream() {
                @Override
                public int read() {
                    return delegate.read();
                }
    
                @Override
                public boolean isFinished() {
                    return false;
                }
    
                @Override
                public boolean isReady() {
                    return false;
                }
    
                @Override
                public void setReadListener(ReadListener listener) {
                    throw new UnsupportedOperationException();
                }
            };
        }
    
        @Override
        public ServletInputStream getInputStream() {
            return body;
        }
    
        /**
         * add a header with given name and value
         */
        private void addHeader(String name, String value) {
            headerMap.put(name, value);
        }
    
        @Override
        public String getHeader(String name) {
            String headerValue = super.getHeader(name);
            if (headerMap.containsKey(name)) {
                headerValue = headerMap.get(name);
            }
            return headerValue;
        }
    
        /**
         * get the Header names
         */
        @Override
        public Enumeration<String> getHeaderNames() {
            List<String> names = Collections.list(super.getHeaderNames());
            names.addAll(headerMap.keySet());
            return Collections.enumeration(names);
        }
    
        @Override
        public Enumeration<String> getHeaders(String name) {
            List<String> values = Collections.list(super.getHeaders(name));
            if (headerMap.containsKey(name)) {
                values = Collections.singletonList(headerMap.get(name));
            }
            return Collections.enumeration(values);
    
        }
    
        private void setHeaderMap(HttpServletRequest request) {
            Enumeration e = request.getHeaderNames();
            while (e.hasMoreElements()) {
                String name = (String) e.nextElement();
                String value = request.getHeader(name);
                addHeader(name, value);
            }
            addHeader("content-type", contentType);
        }
    
        public String getContentType(){
            return contentType;
        }

拦截器

/**
     * HttpServletRequest替换的filter
     *
     * @author qiaofeng
     */
    @Component
    @Slf4j
    public class HttpServletRequestReplacedFilter extends OncePerRequestFilter {
    
        @Override
        protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException {
            //判断宝物基座的逻辑
            String methodType = request.getMethod().toUpperCase();
            System.out.println("请求方式为：" + methodType);
            if ((("POST".equals(methodType)) || ("DELETE".equals(methodType)) || ("PUT".equals(methodType))) && isBaoWuTransmit(request)) {
                ServletRequest requestWrapper = new BodyHttpServletRequestWrapper(request);
                filterChain.doFilter(requestWrapper, response);
            } else{
                filterChain.doFilter(request, response);
            }
        }
    
        private boolean isBaoWuTransmit(HttpServletRequest request) {
            boolean baoWu = false;
            Enumeration e = request.getHeaderNames();
            while (e.hasMoreElements()) {
                String headerName = (String) e.nextElement();
                if ("appcode".equals(headerName)){
                    baoWu = true;
                }
            }
            return baoWu;
        }

[https_blog.csdn.net_qq_34468174_article_details_106665093]: https://blog.csdn.net/qq_34468174/article/details/106665093