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From "Waqar Hassan" <aceofspade1...@gmail.com>
Subject Re: Chat program using derby
Date Tue, 19 Feb 2008 16:34:17 GMT
here is my code,
   String emps="";
        try {
            Class.forName("org.apache.derdy.jdbc.EmbeddedDriver");
            Connection c = null;
            c = DriverManager.getConnection("jdbc:derby://localhost:1527/hris1
[wack on WACK]","wack","wack");
            Statement s = c.createStatement();
            ResultSet rs = s.executeQuery("select empid,empname from
WACK.empInfo");
            while(rs.next()){
            emps = "\n " ;
            emps = rs.getString("empname");
            }
            jTextArea1.setText(emps);
        } catch (ClassNotFoundException ex) {
            ex.printStackTrace();
        }
        catch (SQLException e) {
            e.printStackTrace();
        }

tell why m not having data in the  jTextArea1 ???
Please Help
i want to hav data in  jTextArea1


On 2/19/08, musky <muskvar@gmail.com> wrote:
>
>
> i am using derby server itself like a chat server.
>
> i have two programs:they both have a main thread which creates a user
> interface.
> as the user(say bob) enters his  messages to the other party(say
> alice),they
> are entered into a table say bobtable.
> there is a thread that is invoked periodically that reads unread messages
> from alicetable and displays them to bob and updates the messages as read
> by
> setting the ID field to 1.
>
> the same logic is for alice.
>
> here are the programs:
>
> bob:
> import java.util.Timer;
>
> import java.util.TimerTask;
> import java.sql.*;
>
> import org.eclipse.swt.*;
> import org.eclipse.swt.events.SelectionAdapter;
> import org.eclipse.swt.events.SelectionEvent;
> import org.eclipse.swt.widgets.*;
>
> import org.eclipse.swt.widgets.Button;
> import org.eclipse.swt.widgets.Display;
> import org.eclipse.swt.widgets.Shell;
> import org.eclipse.swt.widgets.Text;
> public class TestTime {
>          DBClass dbobject1=new DBClass();
>          static MainClass mc;
>          static Statement stmt;
>          static Connection conn=null;
>          PreparedStatement pstmt=null;
>          static PreparedStatement pstmt1=null;
>
>          ResultSet rs=null;
>          ResultSet rs1=null;
>
>          static Display d;
>            static Shell s;
>            static Button OK;
>
>          //int id=0;
>
> public static void main(String[] args) throws Exception {
> TestTime t = new TestTime();
>
>
> DBClass dbobject1=new DBClass();
> conn=dbobject1.createConnection("ChatDB1");
> conn.setAutoCommit(false);
> t.stmt = conn.createStatement();
> t.execute();
> //mc=new MainClass();
>
> d = new Display( );
> s = new Shell(d);
> s.setSize(250,250);
> s.setText("A Text Field Example");
>
> final Text text1 = new Text(s, SWT.MULTI | SWT.BORDER);
> text1.setBounds(0,0,250,150);
> OK = new Button(s, SWT.PUSH);
> OK.setBounds(80,170,75,40);
> OK.setText("OK");
> OK.addSelectionListener(new SelectionAdapter( ) {
>           public void widgetSelected(SelectionEvent e)
>           {
>                   String contents = text1.getText( );
>                   text1.setText("");
>
>
>
>                 System.out.println("Push Me Was Pushed");
>                 //System.out.println(contents);
>                 try
>                {
>                //stmt.executeUpdate("lock table bobtable in exclusive
> mode");
>                pstmt1 = conn.prepareStatement("insert into bobtable
> values(?,?)");
>                pstmt1.setInt(1,0);
>                pstmt1.setString(2,contents);
>
>            pstmt1.executeUpdate();
>               System.out.println("inserted "+contents+" into bobtable");
>                }
>                 catch(Exception e1)
>                {System.out.println("could not insert"+e1);}
>
>           }
>
>        });
>
>
> s.open();
>
> while(!s.isDisposed( )){
>    if(!d.readAndDispatch( ))
>        d.sleep( );
> }
>
> System.out.println("Main Method is finishing");
>
> }
>
> private void execute() throws Exception {
> System.out.println(" Tasks scheduled");
> int initialDelay = 1000; // start after 30 seconds
> int period = 2000; // repeat every 5 seconds
> Timer timer = new Timer();
> System.out.println(" Timer set");
>
> DBClass dbobject2=new DBClass();
> final Connection conn2=dbobject2.createConnection("ChatDB1");
> conn2.setAutoCommit(false);
> stmt = conn2.createStatement();
>
>
> //dbclass db=new dbclass();
>
> timer.scheduleAtFixedRate(new TimerTask ()
> {
> public void run()
> {
> //System.out.println("Task Run");
>
> //conn=dbobject1.createConnection("ChatDB1");
>
>
> try
> {
>        //int id=mc.returnflag();
>
>        //System.out.println(id);
>          // System.out.println("Before ExecuteQuery");
>
>    //stmt.executeUpdate("lock table alicetable in share mode");
>
> PreparedStatement pstmt=conn2.prepareStatement("select * from alicetable
> where TID=0");
> //pstmt.setInt(1,id);
>
> rs=pstmt.executeQuery();
> //stmt.executeUpdate("lock table alicetable in exclusive mode");
>
> stmt.executeUpdate("Update alicetable set TID=1 where TID=0");
> //rs1=pstmt.executeQuery();
>
>
> while(rs.next())
>   {
>           String str=rs.getString(2);
>           int str2=rs.getInt(1);
>           System.out.println(str2+"          "+str);
>   }
>
>
> }
>
> catch ( Exception e ) {System.out.println("mhjfdshmnjh  "+e);}
>
> }
> }, initialDelay, period);
> }
> }
>
> alice:
> import java.util.Timer;
>
> import java.util.TimerTask;
> import java.sql.*;
>
> import org.eclipse.swt.*;
> import org.eclipse.swt.events.SelectionAdapter;
> import org.eclipse.swt.events.SelectionEvent;
> import org.eclipse.swt.widgets.*;
>
> import org.eclipse.swt.widgets.Button;
> import org.eclipse.swt.widgets.Display;
> import org.eclipse.swt.widgets.Shell;
> import org.eclipse.swt.widgets.Text;
> public class TestTime2 {
>          DBClass dbobject1=new DBClass();
>          static MainClass mc;
>          Statement stmt;
>          static Connection conn=null;
>          PreparedStatement pstmt=null;
>          static PreparedStatement pstmt1=null;
>      static Text text1;
>          ResultSet rs=null;
>          ResultSet rs1=null;
>
>          static Display d;
>            static Shell s;
>            static Button OK;
>
>          //int id=0;
>
> public static void main(String[] args) throws Exception {
> TestTime2 t = new TestTime2();
>
>
> DBClass dbobject1=new DBClass();
> conn=dbobject1.createConnection("ChatDB1");
> conn.setAutoCommit(false);
> t.execute();
> //mc=new MainClass();
>
> d = new Display( );
> s = new Shell(d);
> s.setSize(250,250);
> s.setText("A Text Field Example");
>
> text1 = new Text(s, SWT.MULTI | SWT.BORDER);
> text1.setBounds(0,0,250,150);
> OK = new Button(s, SWT.PUSH);
> OK.setBounds(80,170,75,40);
> OK.setText("OK");
>
> OK.addSelectionListener(new SelectionAdapter( ) {
>           public void widgetSelected(SelectionEvent e)
>           {
>                   String contents = text1.getText( );
>                   text1.setText("");
>
>
>
>                 System.out.println("Push Me Was Pushed");
>                 //System.out.println(contents);
>                 try
>                {
>                pstmt1 = conn.prepareStatement("insert into alicetable
> values(?,?)");
>                pstmt1.setInt(1,0);
>                pstmt1.setString(2,contents);
>
>            pstmt1.executeUpdate();
>               System.out.println("inserted "+contents+" into alicetable");
>                }
>                 catch(Exception e1)
>                {System.out.println("could not insert"+e1);}
>
>           }
>
>        });
>
>
> s.open();
>
> while(!s.isDisposed( )){
>    if(!d.readAndDispatch( ))
>        d.sleep( );
> }
>
> System.out.println("Main Method is finishing");
>
> }
>
> private void execute() throws Exception {
> System.out.println(" Tasks scheduled");
> int initialDelay = 10000; // start after 30 seconds
> int period = 2000; // repeat every 5 seconds
> Timer timer = new Timer();
> System.out.println(" Timer set");
>
> DBClass dbobject2=new DBClass();
> final Connection conn2=dbobject2.createConnection("ChatDB1");
> conn2.setAutoCommit(false);
> stmt = conn2.createStatement();
> //dbclass db=new dbclass();
>
> timer.scheduleAtFixedRate(new TimerTask ()
> {
> public void run()
> {
> try
> {
> PreparedStatement pstmt=conn2.prepareStatement("select * from bobtable
> where
> TID=0");
> //pstmt.setInt(1,id);
>
> rs=pstmt.executeQuery();
> //stmt.executeUpdate("lock table bobtable in exclusive mode");
>
> stmt.executeUpdate("Update bobtable set TID=1 where TID=0");
> //rs1=pstmt.executeQuery();
>
>
> while(rs.next())
>   {
>           String str=rs.getString(2);
>           int str2=rs.getInt(1);
>           System.out.println(str2+"          "+str);
>           //text1.setText(str2+"                 "+str);
>   }
>
>
> }
>
> catch ( Exception e ) {System.out.println("mhjfdshmnjh  "+e);}
>
> }
> }, initialDelay, period);
> }
> }
>
> when i run both the programs:i get the following exception:mhjfdshmnjh
> java.sql.SQLTransactionRollbackException: A lock could not be obtained
> within the time requested
>
> please help me.
>
> regards.
> --
> View this message in context:
> http://www.nabble.com/Chat-program-using-derby-tp15561400p15561400.html
> Sent from the Apache Derby Users mailing list archive at Nabble.com.
>
>


-- 
! ! ! WACK ! ! !

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