Servlet读取资源文件（文件的下载）

1. 文件名非中文：

package ztq.servlet.study;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

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

public class ServletDemo1 extends HttpServlet {
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        //获取要下载的文件
        ServletContext sc = getServletContext();
        String path = sc.getRealPath("/pic.jpg");
        
        //通知客户端以下载的方式打开
        response.setHeader("Content-Disposition", "attachment;filename = pic.jpg" );
        response.setHeader("Content-type", "application/octet-stream");
        
        //构建输入输出流
        InputStream in = new FileInputStream(path);
        OutputStream out = response.getOutputStream();
        byte[] buf = new byte[1024];
        int len = 0;
        while((len = in.read(buf)) != -1){
            out.write(buf, 0, len);
        }
        in.close();
        out.close();
    }
    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        doGet(request, response);
    }
}

2. 文件名含中文：

package ztq.servlet.study;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URLEncoder;

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

public class ServletDemo1 extends HttpServlet {
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        //获取要下载的文件
        ServletContext sc = getServletContext();
        String path = sc.getRealPath("/人物.jpg");
        
        //截取文件名
        String filename = path.substring(path.lastIndexOf("\") + 1);
        
        //通知客户端以下载的方式打开
        response.setHeader("Content-Disposition", "attachment;filename = " + URLEncoder.encode(filename, "UTF-8"));
        response.setHeader("Content-type", "application/octet-stream");
        
        //构建输入输出流
        InputStream in = new FileInputStream(path);
        OutputStream out = response.getOutputStream();
        byte[] buf = new byte[1024];
        int len = 0;
        while((len = in.read(buf)) != -1){
            out.write(buf, 0, len);
        }
        in.close();
        out.close();
    }
    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        doGet(request, response);
    }
}