Tomcat请求过滤插件

一、参考代码结构

package com.berryz2007.soskp;

//----------------------------------------

// Tomcat 10 用以下的 import

//import jakarta.servlet.http.HttpServlet;

//import jakarta.servlet.http.HttpServletRequest;

//import jakarta.servlet.http.HttpServletResponse;

//----------------------------------------

// Tomcat 9 用以下的 import

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

//----------------------------------------

import javax.servlet.*;

import java.io.File;

import java.io.FileOutputStream;

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 {

        if(!(servletRequest instanceof HttpServletRequest)){

            return;

        }

        HttpServletRequest request = (HttpServletRequest) servletRequest;

        将请求输出到日志

        writeInFile(request.getRequestURI());

        filterChain.doFilter(servletRequest, servletResponse);

    }

    @Override

    public void destroy() {

    }

    public void writeInFile(String str) {

        File f = new File("D:\\test_fi.txt");

        FileOutputStream fos = null;

        try {

            if (!f.exists())

                f.createNewFile();

            fos = new FileOutputStream(f, true);

            String content = str + "\r\n";

            fos.write(content.getBytes());

        } catch (IOException e) {

            e.printStackTrace();

        } finally {

            if (fos != null) {

                try {

                    fos.close();

                } catch (IOException e) {

                    e.printStackTrace();

                }

            }

        }

    }

}