本篇文章给大家分享的是有关如何解决spring 处理request.getInputStream()输入流只能读取一次问题，小编觉得挺实用的，因此分享给大家学习，希望大家阅读完这篇文章后可以有所收获，话不多说，跟着小编一起来看看吧。
一般我们会在InterceptorAdapter拦截器中对请求进行验证
正常普通接口请求，request.getParameter()可以获取，能多次读取
如果我们的接口是用@RequestBody来接受数据，那么我们在拦截器中
需要读取request的输入流 ，因为 ServletRequest中getReader()和getInputStream()只能调用一次
这样就会导致controller 无法拿到数据。
解决方法 ：
1、自定义一个类 BodyReaderHttpServletRequestWrapper.java
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import org.springframework.util.StreamUtils;
/**
* @author WBG
* @date 2020/6/22 10:42
* @describe
*/
public class BodyReaderHttpServletRequestWrapper extends HttpServletRequestWrapper{
private byte[] requestBody = null;//用于将流保存下来
public BodyReaderHttpServletRequestWrapper(HttpServletRequest request) throws IOException {
super(request);
requestBody = StreamUtils.copyToByteArray(request.getInputStream());
}
@Override
public ServletInputStream getInputStream() throws IOException {
final ByteArrayInputStream bais = new ByteArrayInputStream(requestBody);
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) {
}
};
}
@Override
public BufferedReader getReader() throws IOException{
return new BufferedReader(new InputStreamReader(getInputStream()));
}
}2、自定义 MyFilter 继承Filter
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import java.io.BufferedReader;
import java.io.IOException;
/**
* @author WBG
* @date 2020/6/22 14:32
* @describe
*/
public class MyFilter implements Filter {
@Override
public void init(FilterConfig filterConfig) throws ServletException {
System.out.println("开始");
}
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
ServletRequest requestWrapper=null;
if(request instanceof HttpServletRequest) {
requestWrapper=new BodyReaderHttpServletRequestWrapper((HttpServletRequest)request);
}
if(requestWrapper==null) {
chain.doFilter(request, response);
}else {
System.out.println("------------------------------请求报文----------------------------------");
System.out.println(getParamsFromRequestBody((HttpServletRequest) requestWrapper));
System.out.println("------------------------------请求报文----------------------------------");
chain.doFilter(requestWrapper, response);
}
}
/* *
* 获取请求体内容
* @return
* @throws IOException
*/
private String getParamsFromRequestBody(HttpServletRequest request) throws IOException {
BufferedReader br = null;
String listString = "";
try {
br = request.getReader();
String str = "";
while ((str = br.readLine()) != null) {
listString += str;
}
} catch (IOException e) {
e.printStackTrace();
}
return listString;
}
@Override
public void destroy() {
System.out.println("destroy");
}
}3、web.xm配置过滤器
<!--定义过滤器-->
<filter>
<!--定义过滤器拦截URL地址-->
<filter-name>test2</filter-name>
<!--过滤器的文件-->
<filter-class>com.zhhy.hy2000interface.utils.filter.MyFilter</filter-class>
</filter>
<filter-mapping>
<!--过滤器的名称-->
<filter-name>test2</filter-name>
<!--过滤器负责拦截的URL-->
<!-- /* 会把所有的请求拦截下来 -->
<url-pattern>/*</url-pattern>
</filter-mapping>
（如果是Springboot，使用注解即可）
以上就是如何解决spring 处理request.getInputStream()输入流只能读取一次问题，小编相信有部分知识点可能是我们日常工作会见到或用到的。希望你能通过这篇文章学到更多知识。更多详情敬请关注天达云行业资讯频道。