shan shan - 2 months ago 14
MySQL Question

Database restoring with java code - program not responding

I'm trying to restore a backed up .sql file using Java program. I'm posting the method below. But when I execute this the program halts for a long time. Then I executed same mysql command in command line(Windows) it's works charmingly.

Puzzled where I missed. What do you think ?

File file;
final JFileChooser fc = new JFileChooser();
int returnVal = fc.showOpenDialog(this);

if (returnVal == JFileChooser.APPROVE_OPTION) {
file = fc.getSelectedFile();

try {
System.out.println(file.getCanonicalPath());

String executeCmd = "mysql -u " + username + " -p" + password +" " + dbName+" < "+" \" "+file.getCanonicalPath()+"\" " ;
Process runtimeProcess;
runtimeProcess = Runtime.getRuntime().exec(executeCmd);
int processComplete = runtimeProcess.waitFor();
if (processComplete == 0) {

JOptionPane.showMessageDialog(Interface.mainFrame, "Database Backup restored successfully.", "Netmetering", 1);
} else {
System.out.println("Could not restore the backup");
}
} catch (IOException | InterruptedException ex) {}


...

Answer
String executeCmd = "mysql -u " + username + " -p" + password +" " + dbName+" < "+" \" "+file.getCanonicalPath()+"\" " ;
Process runtimeProcess = Runtime.getRuntime().exec(executeCmd);
InputStream is = runtimeProcess.getInputStream();

// Do one OR the other, but not both ;)

// If you don't care about the output, but I think it's a bit of waste personally...
while (is.read() != -1) {}

// I'd at least dump the output to the console...
int byteRead = -1;
while ((byteRead = is.read()) != -1) {
    System.out.print((char)byteRead );
}

int processComplete = runtimeProcess.waitFor();
if (processComplete == 0) {...}

I would also recommend using ProcessBuilder over creating the Process manually like this, it handles the parameters better - IMHO