I can not get data from Table cell

[sahm]

I can not get data from Table cell


Hi every one
I try to get String from cell in jTable
every time I try to get data from cell I only get null
and this is my code
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Class.forName("com.mysql.jdbc.Driver");
Connection con;
con = DriverManager.getConnection("jdbc:mysql://localhost/
uni","root","java");
Statement stat = con.createStatement();
ResultSet result;
result = stat.executeQuery("select max(no) from student_info_table");
result.next();
int mx, c;
mx = result.getInt(1);
mx = mx +1;


String inserting_Data = "insert into fee_part_table (feeNO, feeParts,
fee_1st_part) values(?, ?, ?)";
PreparedStatement ps = null;
ps = con.prepareStatement(inserting_Data);

ps.setInt(1, mx);
ps.setInt(2, c);

String st;
st = String.valueOf(jTable2.getValueAt(0, 0));

JOptionPane.showMessageDialog(this, st);

ps.setString(3, String.valueOf(jTable2.getValueAt(0, 0)));
ps.executeUpdate();
///////////////////////////////////////////////

 

[RedGrittyBrick]

I can not get data from Table cell

Multiposted.
http://www.cs.tut.fi/~jkorpela/usenet/xpost.html

 

[Roedy Green]

st = String.valueOf(jTable2.getValueAt(0, 0));

The code that holds the key to your problem is your declaration of
jTable2 and where you store values in jTable2. I don't see that in
your snippet.
See http://mindprod.com/jgloss/sscce.html

 

[Andrew Thompson]

I can not get data from Table cell ...
I try to get String from cell in jTable

Unless you mean JTable, I do not know the class
you are referring to, and if you *are* referring to
JTable, please take care to use the correct
capitalisation.

every time I try to get data from cell I only get null
and this is my code

(snip snippets)

These are code snippets. They do not even compile here,
let alone display the problem. Perhaps if you prepared an
SSCCE* and copy/pasted the first 10-20 lines of the Exception
Stacktrace that occurs, you would have a better chance of
being helped.

* <http://www.physci.org/codes/sscce.html>

--
Andrew Thompson
http://www.athompson.info/andrew/

Message posted via JavaKB.com
http://www.javakb.com/Uwe/Forums.aspx/java-general/200709/1

 

[Lew]

Unless you mean JTable, I do not know the class
you are referring to, and if you *are* referring to
JTable, please take care to use the correct
capitalisation.

* <http://www.physci.org/codes/sscce.html>

You only need to load the class once, not every time you make a connection.

Why not
Connection con =
DriverManager.getConnection( "jdbc:mysql://localhost/uni", "root", "java" );
?

Why not
ResultSet result =
stat.executeQuery( "select max(no) from student_info_table" );
?

Are you sure, result.next() returns true?

You set mx to a value, then increment it separately instead of in one
statement, and you don't ever set a value for c.

Why initialize ps then immediately discard the initial value?

c was never set.

Why not
String st = String.valueOf( jTable2.getValueAt(0, 0) );
?

Intermingling GUI and DB code like this is not good structure. You should
also be sure that GUI code runs on the Event Dispatch Thread (EDT) and that
the database code does not.

Roedy Green said:

... you posted this twice independently. This splits the discussion.
Don't do this. See

<http://mindprod.com/jgloss/multiposting.html>

 

[apm35]

Intermingling GUI and DB code like this is not good structure. You should
also be sure that GUI code runs on the Event Dispatch Thread (EDT) and that
the database code does not.

I'd put it a bit stronger than that. Intermingling GUI and DB code
like this means that the GUI may not work properly since GUI work must
be done in the EDT in order for swing to function properly. Also, when
in the EDT, non-GUI work must be shunted off to a different thread so
that the EDT is only doing GUI work.

-Andrew Marlow