问题：
查阅资料后得知：在Spring中request的只能被获取一次，拦截器获取之后就会导致Controller拿不到值，因为我写了个拦截器，去拦截获取的参数，对参数进行校验加密（也就是上一篇的防篡改功能），然后拦截器验证没问题，controller获取的json类型的数据却是空的
解决办法
写过滤器重新把流再塞回去
1.创建个类，为了备份request中的值
public class MyHttpServletRequestWrapper extends HttpServletRequestWrapper {
private final byte[] buff;
public MyHttpServletRequestWrapper(HttpServletRequest request) throws IOException {
super(request);
InputStream is = request.getInputStream();
ByteArrayOutputStream baos = new ByteArrayOutputStream();
byte[] b = new byte[1024];
int len;
while ((len = is.read(b)) != -1) {
baos.write(b, 0, len);
}
buff = baos.toByteArray();
}
@Override
public ServletInputStream getInputStream() throws IOException {
final ByteArrayInputStream bais = new ByteArrayInputStream(buff);
return new ServletInputStream() {
@Override
public int read() throws IOException {
return bais.read();
}
};
}
@Override
public BufferedReader getReader() throws IOException {
return new BufferedReader(new InputStreamReader(getInputStream()));
}
}
2.创建一个Filter，将该拦截器配置在项目中，为了调用备份的HttpServletRequestWrapper
public class MyRequestBodyFilter implements Filter {
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
@Override
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
HttpServletRequest httpServletRequest = (HttpServletRequest) servletRequest;
servletRequest = new MyHttpServletRequestWrapper(httpServletRequest);
filterChain.doFilter(servletRequest, servletResponse);
}
@Override
public void destroy() {
}
}
3.创建一个工具类，在拦截器中获取request的值
public class RequestUtils {
public static String getRequestValue(HttpServletRequest request) throws IOException {
StringBuffer sb = new StringBuffer();
MyHttpServletRequestWrapper myHttpServletRequestWrapper = new MyHttpServletRequestWrapper(request);
InputStream is = myHttpServletRequestWrapper.getInputStream();
BufferedReader br = new BufferedReader(new InputStreamReader(is));
String str;
while ((str = br.readLine()) != null) {
sb.append(str);
}
return sb.toString();
}
}
当以上创建过后，写的SignAuthInterceptor类就可以正常进行验证防篡改功能了，并且通过request获取的流，也可以通过Controller类拿到每个参数值了；