java实现mySQL数据库的备份与恢复

来源：互联网发布：食品数据分析咨询公司编辑：程序博客网时间：2024/06/05 03:56

释：使用java来实现数据库的备份和恢复其原理相当简单，就是调用mysql控制台，执行其语法。

其下为生成文件保存的磁盘上并提下载。

一、数据库的备份

import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.text.SimpleDateFormat;
import java.util.Date;

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

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

import com.zyiot.constant.Constant;
import com.zyiot.util.PropertiesUtil;

@Controller
@RequestMapping("/backup")
public class BackupDataBaseController extends BaseController {

    @RequestMapping("/database")
   public void backUpDatabase(HttpServletRequest request, HttpServletResponse response) {
        //备份文件路径
       String downloadPath = PropertiesUtil.getProperties(Constant.DOWNLOAD_PATH);

//数据库地址

String databaseIP = PropertiesUtil.getProperties(Constant.DATABASE_IP);

//备份数据库名称

String dataBaseName = PropertiesUtil.getProperties(Constant.DATABASE_NAME);

//数据库用户名

String username = PropertiesUtil.getProperties(Constant.DATABASE_USERNAME);

//数据库用户密码

String password = PropertiesUtil.getProperties(Constant.DATABASE_PASSWORD);

//数据库可执行命令地址

//例：D://MySQL//MySQL Server 5.5//bin//

        String mysqlCmd = PropertiesUtil.getProperties(Constant.MYSQL_CMD);

       Date date = new Date();
       SimpleDateFormat df = new SimpleDateFormat("yyyyMMddHHmm");

// 用于生成备份文件名

        String dataflag = df.format(date);

       // 备份文件名
       String fileName = dataBaseName + dataflag + ".sql";

       // 数据库备份地址，也是数据库文件导出地址
       String downloadURL = downloadPath + fileName;

File dodir = new File(downloadPath);
File dofile = new File(downloadURL);

//判断是否为文件夹

//文件夹不存在并创建

        if (!dodir.exists() && !dodir.isDirectory()) {
           dodir.mkdir();
       }

//文件不存在并创建

        if (!dofile.exists()) {
           try {
               dofile.createNewFile();
           } catch (IOException e) {
               e.printStackTrace();
           }
       }
       Runtime rt = Runtime.getRuntime();

       try {

// 调用调用mysql的安装目录的命令

            Process child = rt.exec(mysqlCmd + "mysqldump -h " + databaseIP + " -u" + username + " -p" + password + " "+ dataBaseName);
           InputStream in = child.getInputStream();// process的输出信息作为输入流

           // 字节流转换成字符流，并设置输出流编码为utf-8，避免从流中读入的是乱码
           InputStreamReader inr = new InputStreamReader(in, "utf-8");

           String inStr;
           StringBuffer sb = new StringBuffer("");
           String outStr;
           // 组合process输出信息字符串
           BufferedReader br = new BufferedReader(inr);
           while ((inStr = br.readLine()) != null) {
               sb.append(inStr + "\r\n");
           }
           outStr = sb.toString();

           // 要用来做备份用的sql目标文件：
           FileOutputStream fout = new FileOutputStream(downloadURL);
           OutputStreamWriter writer = new OutputStreamWriter(fout, "utf-8");
           writer.write(outStr);
           writer.flush();
           in.close();
           inr.close();
           br.close();
           writer.close();
           fout.close();

       } catch (IOException e1) {
           e1.printStackTrace();
       }

       try {
           // 读取备份文件，供客户端下载
           File file = new File(downloadURL);

//设置响应信息

            response.setContentType("application/x-msdownload");
           response.setContentLength((int) file.length());
           response.setHeader("Content-Disposition", "attachment;filename=" + fileName);
           // 流化文件
           FileInputStream fis;

           fis = new FileInputStream(file);

           BufferedInputStream buff = new BufferedInputStream(fis);
           // 用于保存每次读取的字节和读取的长度
           byte[] b = new byte[1024];
           // 该值用于计算当前实际读取了多少字节
           long k = 0;
           // 从response对象中得到输出流,准备下载
           OutputStream myout = response.getOutputStream();
           // 开始循环下载
           while (k < file.length()) {
               int j = buff.read(b, 0, 1024);
               k += j;
               // 将b中的数据写到客户端的内存
               myout.write(b, 0, j);
           }
           myout.flush();
           buff.close();
       } catch (FileNotFoundException e) {
           e.printStackTrace();
       } catch (IOException e) {
           e.printStackTrace();
       }
   }
}

二、数据库的恢复

其参数和备份参数基本相同，原理相当简单，看懂备份，就能看懂恢复。

public void recover() {
                try {

                    Runtime rt = Runtime.getRuntime();

                    // 调用 mysql 的 cmd:
                    Process child = rt.exec(mysqlCmd + "mysql.exe -h " + databaseIP + " -u" + username + " -p" + password + " "+ dataBaseName);
                    /**

*process的输入信息作为输出流

*其和备份原理相似，一个是输出，一个是输入

                   OutputStream out = child.getOutputStream();
                    String inStr;
                    StringBuffer sb = new StringBuffer("");
                    String outStr;
                    BufferedReader br = new BufferedReader(new InputStreamReader(
                            new FileInputStream(downloadURL), "utf-8"));
                    while ((inStr = br.readLine()) != null) {
                        sb.append(inStr + "\r\n");
                    }
                    outStr = sb.toString();

                    OutputStreamWriter writer = new OutputStreamWriter(out, "utf-8");
                    writer.write(outStr);
                    writer.flush();
                    out.close();
                    br.close();
                    writer.close();
                } catch (Exception e) {
                    e.printStackTrace();
                }

            }

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