Read request parameters in interceptor to solve the problem that it can't be read again in controller

Read request parameter in directory interceptor. When controller can't read new class and add filter twice, controller can't get body parameter again. Solution 1. Get body information 2. Rewrite 3. Register filter

request parameters are read in interceptor, but cannot be read twice in controller

New class

package com.ouyeelbuy.mc.common.base; 
import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.*;
 
/**
 * @author robin.zhang
 * @date $
 * @description  Solve in request The data stream of can only be read 1 The problem of times 
 */
public class RequestWrapper extends HttpServletRequestWrapper {
    private final String body;
    public RequestWrapper(HttpServletRequest request) {
        super(request);
        StringBuilder stringBuilder = new StringBuilder();
        BufferedReader bufferedReader = null;
        InputStream inputStream = null;
        try {
            inputStream = request.getInputStream();
            if (inputStream != null) {
                bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
                char[] charBuffer = new char[128];
                int bytesRead = -1;
                while ((bytesRead = bufferedReader.read(charBuffer)) > 0) {
                    stringBuilder.append(charBuffer, 0, bytesRead);
                }
            } else {
                stringBuilder.append("");
            }
        } catch (IOException ex) {
 
        } finally {
            if (inputStream != null) {
                try {
                    inputStream.close();
                }
                catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (bufferedReader != null) {
                try {
                    bufferedReader.close();
                }
                catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        body = stringBuilder.toString();
    }
 
    @Override
    public ServletInputStream getInputStream() throws IOException {
        final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(body.getBytes());
        ServletInputStream servletInputStream = 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 byteArrayInputStream.read();
            }
        };
        return servletInputStream; 
    }
 
    @Override
    public BufferedReader getReader() throws IOException {
        return new BufferedReader(new InputStreamReader(this.getInputStream()));
    }
 
    public String getBody() {
        return this.body;
    }
}

Add a filter

package com.ouyeelbuy.mc.common.filter;
import com.ouyeelbuy.mc.common.base.RequestWrapper;
import org.springframework.stereotype.Component; 
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
 
/**
 * @author robin.zhang
 * @date $
 * @description  Solve request Data flow can only be read 1 The problem of times 
 */
@Component
public class RequestFilter 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);
        }
        if(requestWrapper == null) {
            filterChain.doFilter(servletRequest, servletResponse);
        } else {
            filterChain.doFilter(requestWrapper, servletResponse);
        }
    }
 
    @Override
    public void destroy() {
    }
}

Then register this filter into the spring container, and the problem is solved!

Parameters in body cannot be obtained again in controller when using interceptors

Error message: It can be seen from the error message that the io stream has been closed. This is because the interceptor reads the parameter information in body, so that controller cannot read it again.

I/O error while reading input message; nested exception is java.io.IOException: Stream closed

Solution

After the interceptor reads the body information, write the contents to the

1. Get body information

import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.ServletRequest;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.*;
import java.nio.charset.Charset;
 
/**
 *  Save stream 
 */
public class BodyReaderHttpServletRequestWrapper extends HttpServletRequestWrapper {
    private final byte[] body; 
    public BodyReaderHttpServletRequestWrapper(HttpServletRequest request) {
        super(request);
        String sessionStream = getBodyString(request);
        body = sessionStream.getBytes(Charset.forName("UTF-8"));
    }
 
    /**
     *  Acquisition request Body
     *
     * @param request
     * @return
     */
    public String getBodyString(final ServletRequest request) {
        StringBuilder sb = new StringBuilder();
        InputStream inputStream = null;
        BufferedReader reader = null;
        try {
            inputStream = cloneInputStream(request.getInputStream());
            reader = new BufferedReader(new InputStreamReader(inputStream, Charset.forName("UTF-8")));
            String line = "";
            while ((line = reader.readLine()) != null) {
                sb.append(line);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (inputStream != null) {
                try {
                    inputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (reader != null) {
                try {
                    reader.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return sb.toString();
    }
 
    /**
     * Description:  Copy input stream </br>
     *
     * @param inputStream
     * @return</br>
     */
    public InputStream cloneInputStream(ServletInputStream inputStream) {
        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int len;
        try {
            while ((len = inputStream.read(buffer)) > -1) {
                byteArrayOutputStream.write(buffer, 0, len);
            }
            byteArrayOutputStream.flush();
        } catch (IOException e) {
            e.printStackTrace();
        }
        InputStream byteArrayInputStream = new ByteArrayInputStream(byteArrayOutputStream.toByteArray());
        return byteArrayInputStream;
    }
 
    @Override
    public BufferedReader getReader() throws IOException {
        return new BufferedReader(new InputStreamReader(getInputStream()));
    }
 
    @Override
    public ServletInputStream getInputStream() throws IOException { 
        final ByteArrayInputStream bais = new ByteArrayInputStream(body); 
        return new ServletInputStream() {
 
            @Override
            public int read() throws IOException {
                return bais.read();
            }
 
            @Override
            public boolean isFinished() {
                return false;
            }
 
            @Override
            public boolean isReady() {
                return false;
            }
 
            @Override
            public void setReadListener(ReadListener readListener) {
            }
        };
    }
}

2. Rewrite

import org.springframework.core.annotation.Order;
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
//  Indicates the order in which the filter is executed. The smaller the value, the more it is executed first 
@Order(1)
//  Configure the addresses to be filtered 
@WebFilter(filterName = "bodyReaderFilter", urlPatterns = "/*")
public class BodyReaderFilter implements Filter {
 
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
//        System.out.println("-------------- Filter initialization ------------");
    }
 
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
//        System.out.println("-------------- Perform filtering operations ------------");
 
        //  Prevent stream reading 1 There will be no more after the second time ,  So you need to continue writing out the stream 
        HttpServletRequest httpServletRequest = (HttpServletRequest) servletRequest;
        ServletRequest requestWrapper = new BodyReaderHttpServletRequestWrapper(httpServletRequest);
        filterChain.doFilter(requestWrapper, servletResponse);
    }
 
    @Override
    public void destroy() {
//        System.out.println("-------------- Filter destruction ------------");
    } 
}

3. Register Filter

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.ServletComponentScan;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.openfeign.EnableFeignClients;
 
@SpringBootApplication
@EnableFeignClients
@EnableDiscoveryClient
//  Register filter annotations 
@ServletComponentScan
public class WebPlatformApplication {
    public static void main(String[] args) {
        SpringApplication.run(WebPlatformApplication.class);
    }
}

After the addition is completed, it runs normally!