如何在过滤器里面修改header的参数

import java.io.IOException;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import javax.servlet.http.HttpServletResponse;

import org.springframework.web.filter.OncePerRequestFilter;

import com.loan.common.CommUtil;
/**
 * 过滤器为了往header里面塞参数
 * @author Administrator
 *
 */
public class ModifyParametersFilter extends OncePerRequestFilter{

    @Override
    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
            throws ServletException, IOException {
        ModifyParametersWrapper mParametersWrapper = new ModifyParametersWrapper(request);
        mParametersWrapper.putHeader("uuid",CommUtil.getUUID());
        filterChain.doFilter(mParametersWrapper, response);
    }
     /**
     * 继承HttpServletRequestWrapper，创建装饰类，以达到修改HttpServletRequest参数的目的
     */
    private class ModifyParametersWrapper extends HttpServletRequestWrapper {
        private final Map<String, String> customHeaders;

        ModifyParametersWrapper(HttpServletRequest request) {
            super(request);
            this.customHeaders = new HashMap<>();
        }

        void putHeader(String name, String value){
            this.customHeaders.put(name, value);
        }

        public String getHeader(String name) {
            // check the custom headers first
            String headerValue = customHeaders.get(name);

            if (headerValue != null){
                return headerValue;
            }
            // else return from into the original wrapped object
            return ((HttpServletRequest) getRequest()).getHeader(name);
        }

        public Enumeration<String> getHeaderNames() {
            // create a set of the custom header names
            Set<String> set = new HashSet<>(customHeaders.keySet());

            // now add the headers from the wrapped request object
            Enumeration<String> e = ((HttpServletRequest) getRequest()).getHeaderNames();
            while (e.hasMoreElements()) {
                // add the names of the request headers into the list
                String n = e.nextElement();
                set.add(n);
            }

            // create an enumeration from the set and return
            return Collections.enumeration(set);
        }
    }
}

参考自 https://www.cnblogs.com/007sx/p/7049514.html