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This article mainly introduces SpringBoot how to achieve multiple read stream related knowledge, the content is detailed and easy to understand, simple and fast operation, has a certain reference value, I believe that after reading this SpringBoot how to achieve multiple read stream article will have a harvest, let's take a look at it.

1)。 There are problems

Stream can only be read once

2)。 target

Multiple read stream

3)。 Solution method

Create a wrapper class

4)。 RequestWrapper

Package com.mazaiting.redeye.wrapper; import com.mazaiting.redeye.utils.StreamUtil;import lombok.extern.slf4j.Slf4j;import org.slf4j.Logger;import org.slf4j.LoggerFactory; import javax.servlet.ReadListener;import javax.servlet.ServletInputStream;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletRequestWrapper;import java.io.BufferedReader;import java.io.ByteArrayInputStream;import java.io.IOException;import java.io.InputStreamReader;import java.nio.charset.Charset / * @ author mazaiting * @ date 2019-06-27 * @ decription HttpServletRequest wrapper * solves the problem that request.getInputStream () can only read once * destination: stream can be read repeatedly * / @ Slf4jpublic class RequestWrapper extends HttpServletRequestWrapper {/ * * log * / private static final Logger mLogger = LoggerFactory.getLogger (RequestWrapper.class); / * * request body * / private String mBody Public RequestWrapper (HttpServletRequest request) {super (request); / / store body data in mBody = getBody (request);} / * get request body * @ param request request * @ return request body * / private String getBody (HttpServletRequest request) {try {return StreamUtil.getString (request.getInputStream ()) } catch (IOException e) {mLogger.debug (e.getMessage ()); throw new RuntimeException (e);}} / * * obtain request body * @ return request body * / public String getBody () {return mBody;} @ Override public BufferedReader getReader () throws IOException {return new BufferedReader (new InputStreamReader (getInputStream () } @ Override public ServletInputStream getInputStream () throws IOException {/ / create byte array input stream final ByteArrayInputStream bais = new ByteArrayInputStream (mBody.getBytes (Charset.defaultCharset (); 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 bais.read ();};}}

5)。 Set filter (must)

@ 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 {ServletRequest requestWrapper = null; if (servletRequest instanceof HttpServletRequest) {requestWrapper = new RequestWrapper ((HttpServletRequest) servletRequest) } / / get the flow in the request, convert the extracted string to the stream again, and then put it in the new request object / / pass the new request object if (null = = requestWrapper) {filterChain.doFilter (servletRequest, servletResponse) in the chain.doFiler method;} else {filterChain.doFilter (requestWrapper, servletResponse) } @ Override public void destroy () {}}

6)。 Use

/ * * * @ author mazaiting * @ date 2019-06-26 * @ decription Session interceptor * / public class SessionInterceptor implements HandlerInterceptor {/ * * * log * / private static final Logger mLogger = LoggerFactory.getLogger (SessionInterceptor.class); @ Override public boolean preHandle (HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {mLogger.debug ("SessionInterceptor") / / get address String url = request.getRequestURL (). ToString (); mLogger.debug ("url:" + url); / / get session HttpSession session = request.getSession (); String id = session.getId (); mLogger.debug ("sessionId:" + id); String requestMethod = request.getMethod (); mLogger.debug ("requestMethod:" + requestMethod) String servletPath = request.getServletPath (); mLogger.debug ("servletPath:" + servletPath); if (isJson (request)) {String body = new RequestWrapper (request). GetBody (); mLogger.debug ("body:" + body);} return true } / * determine whether the data type of this request is json * * @ param request request * @ return true: JSON data False: non-json data * / private boolean isJson (HttpServletRequest request) {if (request.getContentType ()! = null) {return request.getContentType () .equals (MediaType.APPLICATION_JSON_VALUE) | | request.getContentType () .equals (MediaType.APPLICATION_JSON_UTF8_VALUE);} return false }} this is the end of the article on "how to read streams multiple times by SpringBoot". Thank you for reading! I believe you all have a certain understanding of "how to achieve multiple read streams in SpringBoot". If you want to learn more, you are welcome to follow the industry information channel.

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