Question

如何用Java实现MySQL数据库的备份和恢复

Answer 1

将MySql中的数据库导出到文件中 备份
import java.io.*;
import java.lang.*;
public class BeiFen {
public static void main(String[] args) {
// 数据库导出
String user = "root"; // 数据库帐号
String password = "root"; // 登陆密码
String database = "test"; // 需要备份的数据库名
String filepath = "e:\\test.sql"; // 备份的路径地址
String stmt1 = "mysqldump " + database + " -u " + user + " -p"
+ password + " --result-file=" + filepath;/** String mysql="mysqldump test -u root -proot
* --result-file=d:\\test.sql";*/try {Runtime.getRuntime().exec(stmt1);
System.out.println("数据已导出到文件" + filepath + "中");}catch (IOException e) {
e.printStackTrace();}}}
将数据从磁盘上的文本文件还原到MySql中的数据库
importjava.io.*;
importjava.lang.*;/**还原MySql数据库**/publicclassRecover{
publicstaticvoidmain(String[]args){
Stringfilepath="d:\\test.sql";//备份的路径地址
//新建数据库test

Answer 2

用Java实现MySQL数据库的备份和恢复的实现方法是通过命令行调用mysqldump命令和恢复命令mysql来实现备份和恢复的。备份和恢复所使用的文件都是sql文件。
参考实现代码如下：
package xxx.utils;
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.io.PrintWriter;
import java.io.UnsupportedEncodingException;
/**
* MySQL数据库的备份与恢复 缺陷：可能会被杀毒软件拦截
*
* @author xxx
* @version xxx
*/
public class DatabaseBackup {
/** MySQL安装目录的Bin目录的绝对路径 */
private String mysqlBinPath;
/** 访问MySQL数据库的用户名 */
private String username;
/** 访问MySQL数据库的密码 */
private String password;
public String getMysqlBinPath() {
return mysqlBinPath;
}
public void setMysqlBinPath(String mysqlBinPath) {
this.mysqlBinPath = mysqlBinPath;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public DatabaseBackup(String mysqlBinPath, String username, String password) {
if (!mysqlBinPath.endsWith(File.separator)) {
mysqlBinPath = mysqlBinPath + File.separator;
}
this.mysqlBinPath = mysqlBinPath;
this.username = username;
this.password = password;
}
/**
* 备份数据库
*
* @param output
* 输出流
* @param dbname
* 要备份的数据库名
*/
public void backup(OutputStream output, String dbname) {
String command = "cmd /c " + mysqlBinPath + "mysqldump -u" + username
+ " -p" + password + " --set-charset=utf8 " + dbname;
PrintWriter p = null;
BufferedReader reader = null;
try {
p = new PrintWriter(new OutputStreamWriter(output, "utf8"));
Process process = Runtime.getRuntime().exec(command);
InputStreamReader inputStreamReader = new InputStreamReader(process
.getInputStream(), "utf8");
reader = new BufferedReader(inputStreamReader);
String line = null;
while ((line = reader.readLine()) != null) {
p.println(line);
}
p.flush();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (reader != null) {
reader.close();
}
if (p != null) {
p.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* 备份数据库，如果指定路径的文件不存在会自动生成
*
* @param dest
* 备份文件的路径
* @param dbname
* 要备份的数据库
*/
public void backup(String dest, String dbname) {
try {
OutputStream out = new FileOutputStream(dest);
backup(out, dbname);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
/**
* 恢复数据库
*
* @param input
* 输入流
* @param dbname
* 数据库名
*/
public void restore(InputStream input, String dbname) {
String command = "cmd /c " + mysqlBinPath + "mysql -u" + username
+ " -p" + password + " " + dbname;
try {
Process process = Runtime.getRuntime().exec(command);
OutputStream out = process.getOutputStream();
String line = null;
String outStr = null;
StringBuffer sb = new StringBuffer("");
BufferedReader br = new BufferedReader(new InputStreamReader(input,
"utf8"));
while ((line = br.readLine()) != null) {
sb.append(line + "/r/n");
}
outStr = sb.toString();
OutputStreamWriter writer = new OutputStreamWriter(out, "utf8");
writer.write(outStr);
writer.flush();
out.close();
br.close();
writer.close();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 恢复数据库
*
* @param dest
* 备份文件的路径
* @param dbname
* 数据库名
*/
public void restore(String dest, String dbname) {
try {
InputStream input = new FileInputStream(dest);
restore(input, dbname);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
Configuration config = HibernateSessionFactory.getConfiguration();
String binPath = config.getProperty("mysql.binpath");
String userName = config.getProperty("connection.username");
String pwd = config.getProperty("connection.password");
DatabaseBackup bak = new DatabaseBackup(binPath, userName, pwd);
bak.backup("c:/ttt.sql", "ttt");
bak.restore("c:/ttt.sql", "ttt");
}
}

Answer 3

MySQL的一些前台工具是有备份恢复功能的，可是如何在我们的应用程序中实现这一功能呢？本文提供了示例代码来说明如何使用Java代码实现MySQL数据库的备份恢复。

本次实现是使用了MySQL数据库本身提供的备份命令mysqldump和恢复命令mysql，在java代码中通过从命令行调用这两条命令来实现备份和恢复。备份和恢复所使用的文件都是sql文件。

本代码是参照网上某网友提供的源码完成的。

[java] view plaincopy
package xxx.utils;
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.io.PrintWriter;
import java.io.UnsupportedEncodingException;
/**
* MySQL数据库的备份与恢复 缺陷：可能会被杀毒软件拦截
*
* @author xxx
* @version xxx
*/
public class DatabaseBackup {
/** MySQL安装目录的Bin目录的绝对路径 */
private String mysqlBinPath;
/** 访问MySQL数据库的用户名 */
private String username;
/** 访问MySQL数据库的密码 */
private String password;
public String getMysqlBinPath() {
return mysqlBinPath;
}
public void setMysqlBinPath(String mysqlBinPath) {
this.mysqlBinPath = mysqlBinPath;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public DatabaseBackup(String mysqlBinPath, String username, String password) {
if (!mysqlBinPath.endsWith(File.separator)) {
mysqlBinPath = mysqlBinPath + File.separator;
}
this.mysqlBinPath = mysqlBinPath;
this.username = username;
this.password = password;
}
/**
* 备份数据库
*
* @param output
* 输出流
* @param dbname
* 要备份的数据库名
*/
public void backup(OutputStream output, String dbname) {
String command = "cmd /c " + mysqlBinPath + "mysqldump -u" + username
+ " -p" + password + " --set-charset=utf8 " + dbname;
PrintWriter p = null;
BufferedReader reader = null;
try {
p = new PrintWriter(new OutputStreamWriter(output, "utf8"));
Process process = Runtime.getRuntime().exec(command);
InputStreamReader inputStreamReader = new InputStreamReader(process
.getInputStream(), "utf8");
reader = new BufferedReader(inputStreamReader);
String line = null;
while ((line = reader.readLine()) != null) {
p.println(line);
}
p.flush();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (reader != null) {
reader.close();
}
if (p != null) {
p.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* 备份数据库，如果指定路径的文件不存在会自动生成
*
* @param dest
* 备份文件的路径
* @param dbname
* 要备份的数据库
*/
public void backup(String dest, String dbname) {
try {
OutputStream out = new FileOutputStream(dest);
backup(out, dbname);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
/**
* 恢复数据库
*
* @param input
* 输入流
* @param dbname
* 数据库名
*/
public void restore(InputStream input, String dbname) {
String command = "cmd /c " + mysqlBinPath + "mysql -u" + username
+ " -p" + password + " " + dbname;
try {
Process process = Runtime.getRuntime().exec(command);
OutputStream out = process.getOutputStream();
String line = null;
String outStr = null;
StringBuffer sb = new StringBuffer("");
BufferedReader br = new BufferedReader(new InputStreamReader(input,
"utf8"));
while ((line = br.readLine()) != null) {
sb.append(line + "/r/n");
}
outStr = sb.toString();
OutputStreamWriter writer = new OutputStreamWriter(out, "utf8");
writer.write(outStr);
writer.flush();
out.close();
br.close();
writer.close();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 恢复数据库
*
* @param dest
* 备份文件的路径
* @param dbname
* 数据库名
*/
public void restore(String dest, String dbname) {
try {
InputStream input = new FileInputStream(dest);
restore(input, dbname);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
Configuration config = HibernateSessionFactory.getConfiguration();
String binPath = config.getProperty("mysql.binpath");
String userName = config.getProperty("connection.username");
String pwd = config.getProperty("connection.password");
DatabaseBackup bak = new DatabaseBackup(binPath, userName, pwd);
bak.backup("c:/ttt.sql", "ttt");
bak.restore("c:/ttt.sql", "ttt");
}
}

最后的main方法只是一个简单的使用方法的示例代码。
本人所做的项目是使用了hibernate的，而这里需要提供MySQL的bin路径和用户名、密码，而hibernate.cfg.xml中本身就是需要配置数据库的用户名和密码，所以我把MySQL的bin路径也直接配置到了这个文件里面，也不需要创建专门的配置文件，不需要写读取配置文件的接口了。
如果不明白，可以去看hibernate.cfg.xml的说明，里面是可以配置其他的property的