【SSM】AppFileUtils

package com.kikyo.sys.utils;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.net.URLEncoder;
import java.util.Properties;

import javax.servlet.http.HttpServletResponse;

import org.apache.commons.io.FileUtils;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;

public class AppFileUtils {

    /**
     * 得到文件上传的路径
     */
    public static String PATH = "E:/upload/";

    static {
        InputStream stream = AppFileUtils.class.getClassLoader().getResourceAsStream("config/file.properties");
        Properties properties = new Properties();
        try {
            properties.load(stream);
            PATH = properties.getProperty("path");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }


    /**
     * 文件下载
     *
     * @param response
     * @param path
     * @param oldName
     * @return
     */
    public static ResponseEntity<Object> downloadFile(HttpServletResponse response, String path, String oldName) {
        //4,使用绝对路径+相对路径去找到文件对象
        File file = new File(AppFileUtils.PATH, path);
        //5,判断文件是否存在
        if (file.exists()) {
            try {
                try {
                    //如果名字有中文 要处理编码
                    oldName = URLEncoder.encode(oldName, "UTF-8");
                } catch (Exception e) {
                    e.printStackTrace();
                }
                //把file转成一个bytes
                byte[] bytes = FileUtils.readFileToByteArray(file);
                HttpHeaders header = new HttpHeaders();
                //封装响应内容类型(APPLICATION_OCTET_STREAM 响应的内容不限定)
                header.setContentType(MediaType.APPLICATION_OCTET_STREAM);
                //设置下载的文件的名称
                header.setContentDispositionFormData("attachment", oldName);
                //创建ResponseEntity对象
                ResponseEntity<Object> entity = new ResponseEntity<Object>(bytes, header, HttpStatus.CREATED);
                return entity;
            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
        } else {
            PrintWriter out;
            try {
                out = response.getWriter();
                out.write("文件不存在");
                out.flush();
                out.close();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            return null;
        }
    }


    /**
     * 根据相对路径删除硬盘上文件
     *
     * @param path2
     */
    public static void deleteFileUsePath(String path) {
        String realPath = PATH + path;
        //根据文件
        File file = new File(realPath);
        if (file.exists()) {
            file.delete();
        }
    }
}