示例：Servlet读取文件内容并在页面打印输出

 package com.mhb;

 import java.io.BufferedReader;
 import java.io.File;
 import java.io.FileReader;
 import java.io.IOException;
 import java.io.PrintWriter;

 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;

 public class FileRead extends HttpServlet {

 public void init() throws ServletException {
 }

 public void doGet(HttpServletRequest request, HttpServletResponse response)
 throws ServletException, IOException {
 response.setContentType("text/html");     //设置响应内容格式
 response.setCharacterEncoding("gb2312");    //设置响应内容编码
 PrintWriter out = response.getWriter();     //获得out对象
 String fileName = "content.txt";     //指定文件名称
 String realPath = request.getRealPath(fileName);

 File file = new File(realPath);

 if(file.exists()){
 FileReader reader = new FileReader(file);    //获得输入流
 BufferedReader bufferReader = new BufferedReader(reader); //使用缓冲流
 String line = null;     //每行数据
 while ((line = bufferReader.readLine()) != null){    //循环读取
 out.print(line +"<br />");     //输出文件内容
 }
 }else{
 out.print("文件不存在！");
 }

 }

 public void doPost(HttpServletRequest request, HttpServletResponse response)
 throws ServletException, IOException {
 }

 public void destroy() {
 super.destroy();
 }
 }

文本文件：content.txt内容

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