使用java命令在mysql中恢复数据库

Question

这是我使用java命令恢复mysql数据库的代码

当我调试代码时，它会卡在运行时进程中。waitFor（）

有谁能为这个问题提供解决方案吗

public static boolean restoreDB(String dbUserName, String dbPassword,String dbName, String path) {

    String command ="mysql -u"+dbUserName+" -p"+dbPassword+" "+dbName+" < \""+path+"\"";

    Process runtimeProcess;
    try {

        runtimeProcess = Runtime.getRuntime().exec(command);
        int processComplete = runtimeProcess.waitFor();

        if (processComplete == 0) {
            System.out.println("Backup restored successfully");
            return true;
        } else {
            System.out.println("Could not restore the backup");
        }
    } catch (Exception ex) {
        ex.printStackTrace();
    }

    return false;
}

Answer 1

我终于找到了答案。。 谢谢大家的支持， 我看到他们中的很多人都有同样的问题，所以这是我给你们的解决方案

我们无法使用运行时执行mysql恢复命令。getRuntime（）。exec（）函数

所以我创建了一个批处理文件，在其中添加了这个mysql恢复命令，并执行了它。工作很好。：）

public static void restoreDB(String dbUserName, String dbPassword,String dbName, String path) {
    try{
        //for linux .bat must replaced with .sh
        String destpath = "D:\\backup\\db.bat";

    //creating batch file 
    PrintWriter writer = new PrintWriter(destpath);
    String command = "mysql -u"+dbUserName+" -p"+dbPassword+" "+dbName+" < \""+path+"\"";
    writer.println(command);
    writer.close();

    //executing batch file
    Process run = Runtime.getRuntime().exec(destpath);
    System.out.println("file created");
    int processComplete = run.waitFor();

        if (processComplete == 0) {
            System.out.println("Backup created successfully");
            //return true;
        } else {
            System.out.println("Could not create the backup");
        }
    }catch(Exception ex)
    {
        ex.printStackTrace();
    }

}

Answer 2

进程可能会阻塞等待输入，或者写入了太多输出，以至于填满了进程输出缓冲区，等待您读取输出。无论哪种方式，只要确保打印出流程的stdout和stderr，就可以获得更多信息：

private static class StreamReader implements Runnable {

    private InputStream stream;
    private volatile boolean finished = false;

    public StreamReader(InputStream stream) {
        this.stream = stream;
    }

    public void run() {
        Scanner scanner = new Scanner(stream);

        while(!finished) {
            System.out.println(scanner.nextLine());          
        }

    }

}

//...
runtimeProcess = Runtime.getRuntime().exec(command);
StreamReader stdoutReader = new StreamReader(runtimeProcess.getInputStream());
StreamReader stderrReader = new StreamReader(runtimeProcess.getErrorStream());
new Thread(stdoutReader).start();
new Thread(stderrReader).start();
int processComplete = -1;
try {
    processComplete = runtimeProcess.waitFor();
} finally {
    stdoutReader.finished = true;
    stderrReader.finished = true;
}