从 Java 为 mysql 数据库进行简单备份和还原

2022-09-02 00:53:43

如何从 java 代码备份 mysql 数据库,以便:

  1. 它的保存路径是动态分配的。
  2. 路径中的空格不会产生问题。
  3. 路径是使用正在执行的 jar 文件生成的。
  4. DBname,DBusername或DBpass是动态分配的。
  5. 创建专用文件夹以保存备份文件。

答案 1

注意:下面给出的代码是解决问题的一种方法,可能不是最好的方法。代码中的所有内容都是可更改的。如果环境变量中没有 mysql,请在 mysqldump 和 mysql 之前添加路径(例如,对于 XAMPP,C:\xampp\mysql\bin\mysqldump)

(希望,这将解决您的问题。花了我一天的时间完全弄清楚一切并正确实施它们)

备份方法:

public static void Backupdbtosql() {
    try {

        /*NOTE: Getting path to the Jar file being executed*/
        /*NOTE: YourImplementingClass-> replace with the class executing the code*/
        CodeSource codeSource = YourImplementingClass.class.getProtectionDomain().getCodeSource();
        File jarFile = new File(codeSource.getLocation().toURI().getPath());
        String jarDir = jarFile.getParentFile().getPath();


        /*NOTE: Creating Database Constraints*/
        String dbName = "YourDBName";
        String dbUser = "YourUserName";
        String dbPass = "YourUserPassword";

        /*NOTE: Creating Path Constraints for folder saving*/
        /*NOTE: Here the backup folder is created for saving inside it*/
        String folderPath = jarDir + "\\backup";

        /*NOTE: Creating Folder if it does not exist*/
        File f1 = new File(folderPath);
        f1.mkdir();

        /*NOTE: Creating Path Constraints for backup saving*/
        /*NOTE: Here the backup is saved in a folder called backup with the name backup.sql*/
         String savePath = "\"" + jarDir + "\\backup\\" + "backup.sql\"";

        /*NOTE: Used to create a cmd command*/
        String executeCmd = "mysqldump -u" + dbUser + " -p" + dbPass + " --database " + dbName + " -r " + savePath;

        /*NOTE: Executing the command here*/
        Process runtimeProcess = Runtime.getRuntime().exec(executeCmd);
        int processComplete = runtimeProcess.waitFor();

        /*NOTE: processComplete=0 if correctly executed, will contain other values if not*/
        if (processComplete == 0) {
            System.out.println("Backup Complete");
        } else {
            System.out.println("Backup Failure");
        }

    } catch (URISyntaxException | IOException | InterruptedException ex) {
        JOptionPane.showMessageDialog(null, "Error at Backuprestore" + ex.getMessage());
    }
}

恢复方法:

public static void Restoredbfromsql(String s) {
        try {
            /*NOTE: String s is the mysql file name including the .sql in its name*/
            /*NOTE: Getting path to the Jar file being executed*/
            /*NOTE: YourImplementingClass-> replace with the class executing the code*/
            CodeSource codeSource = YourImplementingClass.class.getProtectionDomain().getCodeSource();
            File jarFile = new File(codeSource.getLocation().toURI().getPath());
            String jarDir = jarFile.getParentFile().getPath();

            /*NOTE: Creating Database Constraints*/
             String dbName = "YourDBName";
             String dbUser = "YourUserName";
             String dbPass = "YourUserPassword";

            /*NOTE: Creating Path Constraints for restoring*/
            String restorePath = jarDir + "\\backup" + "\\" + s;

            /*NOTE: Used to create a cmd command*/
            /*NOTE: Do not create a single large string, this will cause buffer locking, use string array*/
            String[] executeCmd = new String[]{"mysql", dbName, "-u" + dbUser, "-p" + dbPass, "-e", " source " + restorePath};

            /*NOTE: processComplete=0 if correctly executed, will contain other values if not*/
            Process runtimeProcess = Runtime.getRuntime().exec(executeCmd);
            int processComplete = runtimeProcess.waitFor();

            /*NOTE: processComplete=0 if correctly executed, will contain other values if not*/
            if (processComplete == 0) {
                JOptionPane.showMessageDialog(null, "Successfully restored from SQL : " + s);
            } else {
                JOptionPane.showMessageDialog(null, "Error at restoring");
            }


        } catch (URISyntaxException | IOException | InterruptedException | HeadlessException ex) {
            JOptionPane.showMessageDialog(null, "Error at Restoredbfromsql" + ex.getMessage());
        }

    }

答案 2

如果 Hibernate 配置正确,则为蛋糕:

Session session = HibernateUtil.getSessionFactory().openSession();
// for every table, have the bean implement Serializable and use the next 4 lines
List <TblBean> tblCollection = session.createCriteria(TblBean.class).list();
FileOutputStream backup = new FileOutputStream("backupOf"+TblBean.getClass().getName()+".dat");
ObjectOutputStream backupWriter = new ObjectOutputStream(backup);
backupWriter.write(tblCollection);

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