springboot使用拦截器拦截获取body，接口报错request body is missing

出现这个问题的原因：

首先请求体传递是使用字节流的方式，那也就意味着只能获取一次，在拦截器中获取后，接口就获取不到了，就会报错400；

解决方案：封装HttpServletRequestWrapper，通过过滤器提前获取请求体，存储在封装的对象中

上代码：

package ;

import ;
import .slf4j.Slf4j;
import org.;
import org.;
import ;

import ;
import ;
import ;
import ;
import ;
import ;
import ;
import ;
import ;

/***
 * @author mazaiting
 * @date 2019-06-27
 * @decription HttpServletRequest 包装器
 * 解决: ()只能读取一次的问题
 * 目标: 流可重复读
 */
@Slf4j
public class RequestWrapper extends HttpServletRequestWrapper {
    /**
     * 日志
     */
    private static final Logger mLogger = ();

    /**
     * 请求体
     */
    private String mBody;

    public RequestWrapper(HttpServletRequest request) {
        super(request);
        // 将body数据存储起来
        mBody = getBody(request);
    }

    /**
     * 获取请求体
     * @param request 请求
     * @return 请求体
     */
    private String getBody(HttpServletRequest request) {
        try {
            byte[] bodyBytes = (());
            return new String(bodyBytes, ());
        } catch (IOException e) {
            (());
            throw new RuntimeException(e);
        }
    }

    /**
     * 获取请求体
     * @return 请求体
     */
    public String getBody() {
        return mBody;
    }

    @Override
    public BufferedReader getReader() throws IOException {
        return new BufferedReader(new InputStreamReader(getInputStream()));
    }

    @Override
    public ServletInputStream getInputStream() throws IOException {
        // 创建字节数组输入流
        final ByteArrayInputStream bais = new ByteArrayInputStream((()));

        return new ServletInputStream() {
            @Override
            public boolean isFinished() {
                return false;
            }

            @Override
            public boolean isReady() {
                return false;
            }

            @Override
            public void setReadListener(ReadListener readListener) {

            }

            @Override
            public int read() throws IOException {
                return ();
            }
        };
    }
}

package ;


import ;
import ;

import .*;
import ;
import ;
import ;

@Component
@WebFilter(filterName = "HttpServletRequestFilter", urlPatterns = "/")
@Order(10000)
public class HttpServletRequestFilter implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        String contentType = ();
        String method = "multipart/form-data";

        if (contentType != null && (method)) {
            // 将转化后的 request 放入过滤链中
            request = new StandardServletMultipartResolver().resolveMultipart(request);
        }
        request = new RequestWrapper((HttpServletRequest) servletRequest);
        //获取请求中的流如何，将取出来的字符串，再次转换成流，然后把它放入到新request对象中
        // 在方法中传递新的request对象
        if(null == request) {
            (servletRequest, servletResponse);
        } else {
            (request, servletResponse);
        }
    }

    @Override
    public void destroy() {

    }
}

//拦截器中获取方式
        String body = new RequestWrapper(request).getBody();

问题解决！！！