Is there a way to convert a String to JTextField type?

Question

How do i convert a string data type to JTextField type. I have set of text boxes in a window and i want to fill it from database using a loop. I am constructing a string with the content same as text box name and now i want to change the data type to JTextField.

---EDIT----

  private void formWindowOpened(java.awt.event.WindowEvent evt) {  
    try {   
        int p_id = made_up.p_id;  
        String sql = "SELECT * FROM pos_metrics WHERE p_id='" + p_id + "'";  
        ResultSet rs = mysql_query.execute_mysql(variables.con.conn, sql);  
        int i = 1;  
        while (rs.next()) {  
            Object metricss = "metrics1" + i;  
            Object metricss2 = "metrics2_" + i;  
            Object values = "value" + i;  
            JTextField text1;  
            JTextField text2;  
            JTextField text3;  
            text1 = (JTextField) metricss;  
            text2 = (JTextField) metricss2;  
            text3 = (JTextField) values;  
            text1.setText(rs.getString("pos_metrics1"));  
            text2.setText(rs.getString("pos_metrics2"));  
            text3.setText(rs.getString("pos_value"));  
            i++;  
        }  
    } catch (SQLException ex) {  
        Logger.getLogger(unit_builder.class.getName()).log(Level.SEVERE, null, ex);  
    }  
}

This is my code and i am getting error on the line where i change the type..

Not totally clear here... are you trying to rename the JTextField variables? What is 'text1 = (JTextField) metricss;' intended to do? — Owen, Feb 25 '11 at 00:53
actually Object metricss = "metrics1" + i; in this line i am constructing the textbox name.. metrics11 wil be the name for first loop so then i want to put the value from database field into this 'metrics11' textbox.. i have a textbox with metrics11 already.. — Deepak, Feb 25 '11 at 01:01

MattLBeck · Accepted Answer · 2011-02-25T01:51:30.743

I think this is what you are trying to achieve:

private void formWindowOpened(java.awt.event.WindowEvent evt) {  
    try {   
        int p_id = made_up.p_id;  
        String sql = "SELECT * FROM pos_metrics WHERE p_id='" + p_id + "'";  
        ResultSet rs = mysql_query.execute_mysql(variables.con.conn, sql);  
        int i = 1;  
        while (rs.next()) {  
            String metricss = "metrics1" + i;  
            String metricss2 = "metrics2_" + i;  
            String values = "value" + i;  

            JTextField text1;  
            JTextField text2;  
            JTextField text3;  

            text1.setName(metricss);
            text2.setName(metricss2);  
            text3.setName(values);  

            text1.setText(rs.getString("pos_metrics1"));  
            text2.setText(rs.getString("pos_metrics2"));  
            text3.setText(rs.getString("pos_value"));  
            i++;  
         }  
    } catch (SQLException ex) {  
        Logger.getLogger(unit_builder.class.getName()).log(Level.SEVERE, null, ex);  
    }  
}

setName() sets the name of the JTextField, which will be the current local instance. I don't know if it has a visible effect on the text field though. You might have to use a border.

--edit--

In light of your comment, this is an example of option 2:

--edit 2--

This code does not compile. Class.forName() is being used for the wrong purpose...

private void formWindowOpened(java.awt.event.WindowEvent evt) {  
    try {   
        int p_id = made_up.p_id;  
        String sql = "SELECT * FROM pos_metrics WHERE p_id='" + p_id + "'";  
        ResultSet rs = mysql_query.execute_mysql(variables.con.conn, sql);  
        int i = 1;  
        while (rs.next()) {  
            String metricss = "metrics1" + i;  
            String metricss2 = "metrics2_" + i;  
            String values = "value" + i;  

            JTextField text1 = Class.forName(metricss);
            JTextField text2 = Class.forName(metricss2);  
            JTextField text3 = Class.forName(values);   

            text1.setText(rs.getString("pos_metrics1"));  
            text2.setText(rs.getString("pos_metrics2"));  
            text3.setText(rs.getString("pos_value"));  
            i++;  
         }  
    } catch (SQLException ex) {  
        Logger.getLogger(unit_builder.class.getName()).log(Level.SEVERE, null, ex);  
    }  
}

no this is not i want. i have 12 textboxes already in a frame. i want to put contents into them. for that i need their textbox name rite ? i dont want to change name. i just want to get the name thats it.. and put the value in it.. the loop i am doing is to put the value in different textboxes.. got it ? — Deepak, Feb 25 '11 at 01:14
I think I understand now. In which case you should either stick your JTextFields in three different arrays (`metricss[]`, `metricss2[]`, `values[]`) and loop over these arrays (e.g. `values[i]`) to get the correct instance. Or, to achieve this in exactly the way you are trying, I think `Class.forName()` would work. I would much prefer the 1st option though. — MattLBeck, Feb 25 '11 at 01:23
is it the workign code ? i think its not working...not compiling also.. i will try the other way though... — Deepak, Feb 25 '11 at 01:36
It might help if you show where you first declare those 12 text fields? — MattLBeck, Feb 25 '11 at 01:40
I checked my code with an IDE. It turns out I'm using `Class.forName()` incorrectly and it's a bit more complicated than what I first thought. The array method is the standard way of doing this sort of thing, however. — MattLBeck, Feb 25 '11 at 01:47

score 1 · Answer 2 · answered Feb 25 '11 at 00:41

1

You can create a new textfield or use an existing one, and simply set its value to the string.

answered Feb 25 '11 at 00:41

rayman86

1,385
10
9

Yup that be the one. Just didn't write the code down off the top of my head been a while since I coded in java. – rayman86 Feb 25 '11 at 01:47

Bala R · Answer 3 · 2011-02-25T01:02:06.113

1

jTextField.setText(stringValue);

Here is an example.

EDIT:

instead of doing stuff like

text1 = (JTextField) metricss;

try

text1 = new JTextField();
text1.setText(metricss);

And be sure to add text1 to a container (like JPanel or JFrame)

edited Feb 25 '11 at 01:02

answered Feb 25 '11 at 00:43

Bala R

107,317
23
199
210

but this wil create a new text box rite ? i dont want that.. i have created the textboxes already. all i want is just to get its name.. look at my edit.. – Deepak Feb 25 '11 at 00:50
No, it won't create a new one. jTextField is assumed to be a local field. I think this is what you want. – Mike Feb 25 '11 at 00:53
see i have 12 text boxes and i have to assign values to that 12 text boxes from the database. For doing that i need to uset setText() as you said. but from that 12 text boxes how will it put things in place when i use jTextField.setText(). Which textbox will be treated as local among tat 12 ?? – Deepak Feb 25 '11 at 00:58

score 1 · Answer 4 · answered Feb 25 '11 at 00:44

1

JTextField newTextField = new JTextField(stringVariable);

answered Feb 25 '11 at 00:44

Owen

1,541
1
14
12

again this creates a new textbox rite ? – Deepak Feb 25 '11 at 00:51

score 1 · Answer 5 · answered Feb 25 '11 at 02:46

I have solved the problem by adding list array of type JTextField and then adding the text boxes to the list. then using loop i retrieved the list and made it work!! viola!!! Here is the code block.

List<JTextField> list = new ArrayList<JTextField>(); list.add(value1); list.add(value2); list.add(value3); list.add(value4); list.add(value5); list.add(value6); list.add(metrics1); list.add(metrics2); list.add(metrics3); list.add(metrics4); list.add(metrics5); list.add(metrics6); list.add(metrics2_1); list.add(metrics2_2); list.add(metrics2_3); list.add(metrics2_4); list.add(metrics2_5); list.add(metrics2_6);

try { int p_id = made_up.p_id; String sql = "SELECT * FROM pos_metrics WHERE p_id='" + p_id + "'"; ResultSet rs = mysql_query.execute_mysql(variables.con.conn, sql); int i = 0; while (rs.next()) { JTextField text1 = list.get(i+6); JTextField text2 = list.get(i);

            JTextField text3= list.get(i+12);

            text1.setText(rs.getString("pos_metrics1"));

            text2.setText(rs.getString("pos_value"));
             text3.setText(rs.getString("pos_metrics2"));
            i++;
        }
    } catch (SQLException ex) {
        Logger.getLogger(unit_builder.class.getName()).log(Level.SEVERE, null, ex);
    }

Is there a way to convert a String to JTextField type?

5 Answers5