Mysql Java how?

Hello, I wonder what what would be the best solution to have a Java application access a mysql database over the internet? I am a beginner, so please bear with me. I tried using a MM.Mysql driver from http://mmmysql.sourceforge.net/ but couldn't get it to work. Can I use servlets? I have full control over the mysql server.
Thanks,
Bertil

I don't know why this keep happening. I am using JCreator (www.jcreator.com) and set the project's classpath to the location of the mm.mysql-2.0.6.1.jar driver. Location of driver is (C:\Program Files\Xinox Software\JCreator LE\MyProjects\mysql\).
Compiling works fine, but executing always brings this exeption. Any ideas?
Unable to load driver.
java.lang.ClassNotFoundException: org.gjt.mm.mysql.Driver
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:297)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:286)
at java.lang.ClassLoader.loadClass(ClassLoader.java:253)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:313)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:120)
at connect.main(connect.java:13)
SQLException: No suitable driver
SQLState: 08001
VendorError: 0
Press any key to continue...

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MySQL + Java doesn't work

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Has anybody been able to run Java applications that use JDBC + MySQL in Arch?
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Last edited by karmapolice (2007-05-22 20:48:25)

http://bugs.archlinux.org/task/7256
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Subtle bug in Deitel & Deitel "Java How to Program" book

Merry x mas and happy new year, guys.
I have this applet (which is at the same time runnable and listener) its printed in Deitel & Deitel "Java How to Program" book 3rd ed.
The program works but as you turn on and off the "suspend" checkboxes some of the threads are not notified, so they go to infinite wait state, deadlock. I couldn't figure out what is wrong or how to fix the problem.. please read the code below, or copy and paste this code to your eclipse, its just one file, then play with the check boxes, some of the threads don't wake up after wait... technically they don't shift from WAITING to TIMED_WAITING state.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
* @author
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Thread currentThread = Thread.currentThread();
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wait();
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System.err.println("sleep interrupted");
displayChar = alphabet.charAt(
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for (int i = 0; i < threads.length; i++) {
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for (int i = 0; i < checkboxes.length; i++) {
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Thanks in advance.

Abiel wrote:
No, notifyAll() is used to tell the threads that we're stopping.... see that it's written in the stop() method of the applet. Eg if the user browses away from our applet we set the array of threads to null and notify them all. So notifyAll() makes sense.Yes, it does make sense there too (!!!!!!!).
However, I gave it a try with what u suggested, and it didn't work (as expected) .... Apparently you did not really read my suggestion or my explanation. If you had, you'd have expected it to work and it would have worked.
the problems still remains, some threads are getting in wait state even if their check box is not suspended.Maybe you should add the following code to understand the root cause and solution.
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what could the problem be?Improper use of notify()
With kind regards
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Hi, :)
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I substituted your line and this is the error I'm receiving now:
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Message was edited by:
shuini

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I'm using mysql-connector-java-5.0.8 and mysql version 5.0...Any ideas?
Thanks a lot for your help =)

Its look can't solve the error..I try to change from:
// create a statement
        stmt = conn.createStatement();
        // extract data from the ResultSetto this one as you said:
// create a statement
        stmt = connection.createStatement();
        // extract data from the ResultSetBut the same problem was happen.
After the error it appear this on output windows of NetBean 5.5:
at dataprotect.Main.loginButtonActionPerformed(Main.java:198)
        at dataprotect.Main.access$000(Main.java:17)
        at dataprotect.Main$1.actionPerformed(Main.java:76)
        at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
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        at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
        at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
        at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
        at java.awt.Component.processMouseEvent(Component.java:6038)
        at javax.swing.JComponent.processMouseEvent(JComponent.java:3265)
        at java.awt.Component.processEvent(Component.java:5803)
        at java.awt.Container.processEvent(Container.java:2058)
        at java.awt.Component.dispatchEventImpl(Component.java:4410)
        at java.awt.Container.dispatchEventImpl(Container.java:2116)
        at java.awt.Component.dispatchEvent(Component.java:4240)
        at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4322)
        at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3986)
        at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3916)
        at java.awt.Container.dispatchEventImpl(Container.java:2102)
        at java.awt.Window.dispatchEventImpl(Window.java:2429)
        at java.awt.Component.dispatchEvent(Component.java:4240)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)Edited by: Aiman on Feb 25, 2008 5:43 AM

Mysql java quizz

Dear friends,
I want to make an online quiz system using mysql and java.I am new to Java,however not new to mysql.
Can anyone guide, please.

Examine the problem, break it up into manageable pieces and then find out how to do each piece in java. For example, the first problem might be...
How do I write a simple java program?class HelloWorld {
public static void main(String[] args) {
System.out.println("Hello World!");
}Here is a link to how to do this (and more besides)
http://java.sun.com/docs/books/tutorial/index.html

Using Java, How can I Update, Add, Delete nodes in XML Files.

Hi,
I want to store the student record (like Name, Age, school name, total mark etc.,) as nodes in the XMLfile. Also I should able to Update, Add, Delete any nodes (student record) in the XML file. How can I achieve this...using Java
I am able to read the content of the xml file using xml-parser. But my problem is
updating the xml file.
pls suggest some solutions or links with " example source code"
Thanks :-)

There are 2 kinds of XML parsers : SAX and DOM. DOM seems to suit your need. You can use JAXP APIs to add, delete or change nodes or attributes.
http://java.sun.com/webservices/jaxp/dist/1.1/docs/tutorial/TOC.html provides contents that would satisfy most of the needs.
To save a DOM modified XML file use java IO APIs to write to the same file from which it was read using a Document object ( doc.getNodeValue() ).

[E2010][EWS-XML][JAVA]How to get the properties of meeting rooms in Exchange 2010 using EWS Java API

When you look at meeting room properties in Outlook 2010, you can see 'City', 'Country/Region' and 'Department' information.
Is there any way to get this information using EWS Java API?

Hi Glen,
I am able to understand what u have said, but do not know how to implement it with meeting rooms....
If i am implementing
"Get all appointments between startDate and endDate in the specified folder, including recurring meeting occurrences" in ews-java-api, as you have mentioned above, i am able to get only my appointments from the start date to end date , as i
have given my email id and password, how to get my organization meeting room details, booked or not.
static ExchangeService service = new ExchangeService(ExchangeVersion.Exchange2010_SP2);
public static void main(String[] args) throws Exception {
// TODO Auto-generated method stub
ExchangeCredentials credentials = new WebCredentials("[email protected]", "zzzz");
service.setCredentials(credentials);
try {
System.out.println("Check");
service.autodiscoverUrl("[email protected]",new RedirectionUrlCallback());
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
NameResolutionCollection nameResolutions = service.resolveName("SDB1",ResolveNameSearchLocation.DirectoryOnly, true);
System.out.println("nameResolutions==="+nameResolutions.getCount());
for(NameResolution nameResolution : nameResolutions)
System.out.println("NAME==="+nameResolution.getContact().getDisplayName());
The above code gives me the output like, the meeting room in my organization with word SDB1 are
Output:
nameResolutions===2
NAME===SDB1- TELCON - 1
NAME===SDB1-TELCON - 2
for. eg. I need to know today at what are the appointments in the room SDB1-TELCON2 and who all have booked the room.
I do not know how to implement for the meeting room can you please help me how to give it.
Thanks in advance.

Files and Streams in java -- How to display successive records

Hi,
I developed an application in which I enter name and id in a gui. Each time I enter, the records are added in the sequential file.
Then I have a button to open that file. It also opens.
Then I have a button to read the records(which has name and id) in sequential order. Each time I click next button records should be displayed in their respective text boxes. But, only the 1st record is displyed. Then I get IOException. Why am I not able to move to records after 1st record. How could I disply records till EOF is reached.
Plz see my code for open function and read next function
private void openFile()
input=new ObjectInputStream(new FileInputStream("c:/file.dat"));
openf.setEnabled(false);
readf.setEnabled(true);
private void readNext()
rcrd=(Record)input.readObject();
String val[]= {String.valueOf(rcrd.getId()),rcrd.getName(),rcrd.getAddr()};
gui.setFieldValues(val);
Why am I not able to move to records after 1st record. How could I disply records till EOF is reached.

package files;
import java.io.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import files.FileGui;
import files.Record;
import java.util.*;
import java.lang.*;
public class CreateFile extends JFrame
     private ObjectOutputStream output;
     private FileGui gui;
     private JButton enter, readf, openf;
     private Record rcrd;
     private ObjectInputStream input;
     boolean eof;
     LinkedList link = new LinkedList();
     ListIterator li=link.listIterator();
     public CreateFile()
          super( "Creating sequential file" );
          getContentPane().setLayout( new BorderLayout() );
          gui = new FileGui();
          enter = gui.getTask1();
          enter.setText("Enter");
          enter.setEnabled(true);
          enter.addActionListener(
                    new ActionListener()
                         public void actionPerformed( ActionEvent e )
                              addRecord1();
          addWindowListener(
                    new WindowAdapter()
                         public void windowClosing( WindowEvent e )
                              if(output != null)
                                   closeFile();
                              else
                                   System.exit(0);
          openf = gui.getTask2();
          openf.setText("Open");
          openf.addActionListener(
                    new ActionListener()
                         public void actionPerformed(ActionEvent e)
                              openFile();
readf = gui.getTask3();
          readf.setText("Read Next");
          readf.addActionListener(
                    new ActionListener()
                         public void actionPerformed(ActionEvent e)
                              readFile();
          getContentPane().add(gui, BorderLayout.CENTER);
          setSize(300,200);
          show();
     private void readFile()
                    try
                         rcrd=(Record)input.readObject();
                         String val[]={String.valueOf(rcrd.getId()),rcrd.getName(),rcrd.getAddr()};
                         gui.setFieldValues(val);
                    catch(EOFException eof)
                         System.out.print("EOFException");
                    catch(ClassNotFoundException cnfe)
                         System.out.print("ClassNotFoundException");
                    catch(IOException ioe)
                         System.out.print("IOException");
     private void openFile()
               JFileChooser fileChooser = new JFileChooser();
               fileChooser.setFileSelectionMode(JFileChooser.FILES_ONLY);
               int result = fileChooser.showOpenDialog(this);
               if(result==JFileChooser.CANCEL_OPTION)
                    return;
               File fileName = fileChooser.getSelectedFile();
               if(fileName==null || fileName.getName().equals(""))
                    JOptionPane.showMessageDialog(this, "Invalid file name", "Invalid file name", JOptionPane.ERROR_MESSAGE);
               else
                    try
                         //File fileName=new File("c:/file.txt");
                         input=new ObjectInputStream(new FileInputStream("c:/file.dat"));
                         openf.setEnabled(false);
                         readf.setEnabled(true);
               catch (Exception e)
                    System.out.println("Error in opening file");
     private void closeFile()
          try
               output.close();
               System.exit(0);
          catch(IOException ex)
               JOptionPane.showMessageDialog(this, "Error Closing File", "Error", JOptionPane.ERROR_MESSAGE);
               System.exit(1);
     private void addRecord1()
          String[] fieldValues = gui.getFieldValues();
          if(! fieldValues[0].equals(""))
               try
                    int id=Integer.parseInt(fieldValues[0]);
                    if(id>0)
                         Record rcrd = new Record(id, fieldValues[1], fieldValues[2]);
                         System.out.println(" " +rcrd.getString());
                         link.add(" " +rcrd.getString());
                         //System.out.println("Hello3");
                         FileOutputStream fos = new FileOutputStream("c:/file.dat",true);
                         output = new ObjectOutputStream(fos);
                         output.writeObject(rcrd);
                         output.flush();
                         //gui.clearFields();
                         readf.setEnabled(true);
               catch (NumberFormatException nfe)
                    JOptionPane.showMessageDialog(this, "Incorrect id", "Invalid number formate", JOptionPane.ERROR_MESSAGE);
               catch (IOException io)
                    closeFile();
     public static void main(String args[])
          new CreateFile();
}

Mysql Java how?

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