Question

我需要使用mysqldump

来避免错误并将数据库备份存储在单独的文件路径中

public class NewClass {

    public static void main(String args[]) throws IOException, SQLException {
        String dbName = "test";
        String dbUser = "root";
        String dbPass = "root";
        try {
            String executeCmd = "";
            executeCmd = "mysqldump -u " + dbUser + " -p" + dbPass + " " + dbName + " -r backup.sql";

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

            if (processComplete == 0) {
                System.out.println("Backup taken successfully");
            } else {
                System.out.println("Could not take mysql backup");
            }
        } catch (InterruptedException ex) {
            Logger.getLogger(NewClass.class.getName()).log(Level.SEVERE, null, ex);
        }    

    }
}

错误：运行：线程“main”中的异常java.io.IOException：无法运行程序“mysqldump”：CreateProcess error = 2，系统找不到文件规定在java.lang.ProcessBuilder.start（ProcessBuilder.java:1042）在java.lang.Runtime.exec（Runtime.java:615）在java.lang.Runtime.exec（Runtime.java:448）在java.lang.Runtime.exec（Runtime.java:345） at mypkg.NewClass.main（NewClass.java:27）引起：java.io.IOException：CreateProcess error = 2，系统找不到指定的文件 at java.lang.ProcessImpl.create（Native Method）在java.lang.ProcessImpl。（ProcessImpl.java:288）在java.lang.ProcessImpl.start（ProcessImpl.java:133）在java.lang.ProcessBuilder.start（ProcessBuilder.java:1023） ......还有4个 Java结果：1 建立成功（总时间：0秒）

Answer 1

尝试将完整路径放入mysqldump程序

executeCmd = "/full/path/to/mysqldump -u " + dbUser + " -p" + dbPass + " " + dbName + " -r backup.sql";

我也很想将完整路径放在要写入转储的文件中。

Answer 2

你试过给exec函数一个字符串数组吗？这对我来说很有帮助。

String[] comm = new String[4];
comm[0] = "C:\\Program Files\\MySQL\\MySQL Server 5.1\\bin\\mysqldump"
comm[1] = "-u " + dbUser;
comm[2] = "-p " + dbPass + " " + dbName;
comm[3] = "-r backup.sql";
Process runtimeProcess = Runtime.getRuntime().exec(comm)

因为当使用单个String作为参数时我有一些奇怪的行为......

Answer 3

只需修改

即可

executeCmd = "mysqldump -u " + dbUser + " -p" + dbPass + " " + dbName + " -r backup.sql";

到

executeCmd = "mysqldump -u " + dbUser + " -p" + dbPass + " " + dbName;

并在if-else语句后添加

String str="";

PrintWriter pw = new PrintWriter("path for this file/backup.sql");

Scanner outScanner = new Scanner(runtimeProcess.getInputStream());

while(outScanner.hasNextLine()){

pw.println(outScanner.nextLine());

}

outScanner.close();

pw.close();

Answer 4

我有同样的问题。对我来说，我只是在路径变量中添加了mysql。在路径变量中设置了旧安装。删除它并添加新路径。

拿MySQL备份

4 个答案: