how to get mysql backup using java swing

[Shashika Thiran]

I use mysqldump to get mysql database backup.it's work fine when i try it on dos prompt.
like this..
>mysqldump -u uname -ppassword databaseName>C:/backup.sql

this will create backup.sql file.
then i try this in java

try{
Runtime rt=Runtime.getRuntime();
rt.exec("C:/Programme Files/MySQL/MySQL Server 5.0/bin/mysqldump -u uname -ppassword databaseName>C:/backup.sql");
catch(IoException e){}

It's runs without errors.But nothing happen.No file create.
Can anyone tell me why this is not work...
can anyone help me..

[Maneesh Godbole]

You wouldn't know even if there were any errors. Your catch block is empty! Try putting a print stack trace there and see how it goes.

[Dmitry Mamonov]

Sure, empty catch block is the bad point to find error.
Also, you are running "C:/Programme.exe"
with arguments
1. Files/MySQL/MySQL
2. Server
3. 5.0/bin/mysqldump
etc.
have you any executables with such name?

[Shashika Thiran]

I have printStacktrace() in catch block and file path is fine...it's soething else i think

[Dmitry Mamonov]

Sasika, would you like to trick us posting code which has no relation to you real problem?

with you posted code we have next:
rt.exec("C:/Programme Files/MySQL/MySQL Server 5.0/bin/mysqldump -u uname -ppassword databaseName>C:/backup.sql");

1. http://java.sun.com/javase/6/docs/api/java/lang/Runtime.html#exec(java.lang.String) refers to http://java.sun.com/javase/6/docs/api/java/lang/Runtime.html#exec(java.lang.String,%20java.lang.String[],%20java.io.File)
2. and consequentally to http://java.sun.com/javase/6/docs/api/java/lang/Runtime.html#exec(java.lang.String[],%20java.lang.String[],%20java.io.File)
3. the command line you have passed as factual argument of exec() method is stripped into String[] with
http://java.sun.com/javase/6/docs/api/java/util/StringTokenizer.html

here is example from javadoc

The following is one example of the use of the tokenizer. The code:

         StringTokenizer st = new StringTokenizer("this is a test");
         while (st.hasMoreTokens()) {
             System.out.println(st.nextToken());
         }
     

prints the following output:

         this
         is
         a
         test

So, as I described above, you are executing "C:/Programme" which will be turned by OS "C:/programme.exe" (or .com or .bat).

To evaluate executable "\"C:/Programme Files/MySQL/MySQL Server 5.0/bin/mysqldump\"" you should enclose it's path with quotes, it may help, but I'm not sure.
Or, better, use method: http://java.sun.com/javase/6/docs/api/java/lang/Runtime.html#exec(java.lang.String[],%20java.lang.String[],%20java.io.File)

[Ulf Dittmer]

Yes, Runtime.exec(String[]) is much better than Runtime.exec(String). It saves you from all the trouble about paths containing spaces and parameters needing to be quoted.

Also be sure to handle the input/error/output stream of the child process. This is described in detail in the article "When Runtime.exec() won't" by Daconta. Nobody should use Runtime.exec without reading that.

[Rob Spoor]

Sasika Thiranga wrote:C:/Programme Files/MySQL/MySQL Server 5.0/bin/mysqldump -u uname -ppassword databaseName>C:/backup.sql

1) shouldn't there be a space between -p and password?
2) file redirection like this (using > C:/backup.sql) is handled by the shell (cmd.exe), it is not part of the application. To do the same in Java you would need to get the process' output (through getInputStream()) and copy its contents to a FileOutputStream("C:/backup.sql") manually. This would also solve half of the problems that the article Ulf mentioned is about. (You'll still need to clear getErrorStream().)

[Maneesh Godbole]

Sasika Thiranga wrote:I have printStacktrace() in catch block and file path is fine...it's soething else i think

Thank you for wasting my time by posting code off the cuff.
Please read this: http://faq.javaranch.com/java/PostRealCode

[Shashika Thiran]

Thank you all of u.I got the point now.I'm working on it now.thanks.

[Shashika Thiran]

I found the answer of my problem...
It's simple add -r for >
like this..

    try{
          Runtime.getRuntime().exec("C:\\Program Files\\MySQL\\MySQL Server 5.0\\bin\\mysql -u root -ppword Dname -r C:/backup.sql");
    }catch(Exception e){
        e.printStackTrace();
     }

this is work fine and it create backup.sql file.
now i have problem with restore....

mysqldump -u root -ppword Dname < C:/backup.sql

anyone know the symbol to use instead of "<"

[Rob Spoor]

Have you read my previous post? I told you how you could handle ">" in Java. "<" is similar: call the Process object's getOutputStream(), create an InputStream, and copy the data.

[Shashika Thiran]

now i write code like this..

 FileInputStream in = null;
        try {
            in = new FileInputStream("C:\\backup.sql");
            Process p = Runtime.getRuntime().exec("C:\\Program Files\\MySQL\\MySQL Server 5.0\\bin\\mysql -u root -p123 example");
            OutputStream out = p.getOutputStream();
            byte[] data = new byte[1024];
            int size;
            while ((size = in.read(data)) != -1) {
                out.write(data, 0, size);
            }
        } catch (IOException ex) {
            Logger.getLogger(NewJFrame.class.getName()).log(Level.SEVERE, null, ex);
        }

but it not restore my backup.please help me with this code.
Thanks.

[Rob Spoor]

Are you sure your program name and parameters are correct? Before you used mysqldump, now it's mysql. Also, try flushing the output stream.

And please http://faq.javaranch.com/java/UseCodeTags

[Shashika Thiran]

finally i manage to find the way to restore using this code.
think this gone help others too

String[] executeCmd = new String[]{"C:\Program Files\MySQL\MySQL Server 5.0\bin\mysql", "databaseName", "--user=uname" , "--password=pword", "-e", " source c:/data/sample.sql" };
Process runtimeProcess =Runtime.getRuntime().exec(executeCmd);