looping jtextfields so it clears if anything but an integer is entered

Question

I know i need this code looped but I'm not sure how to do it, like i don't know what to have as the loop? it clears all the textfields at the minute, but i only want the textfield that has anything but an integer cleared. any help would be appreciated.

try {
    int a = Integer.parseInt(theApp.tred.getText());
    int b = Integer.parseInt(theApp.tgreen.getText()); // uses
                                                        // information
                                                        // entered
    int c = Integer.parseInt(theApp.tblue.getText());

    if (a < 0) {
        a = 200; // if statements for values above and below the targets
                            // set
        tred.setText("200");
    }

    if (a > 255) {
        a = 255;
        tred.setText("255");
    }
    if (b < 0) {
        b = 200;
        tgreen.setText("200");
    }

    if (b > 255) {
        b = 255;
        tgreen.setText("255");
    }

    if (c < 0) {
        c = 200;
        tblue.setText("200");
    }
    if (c > 255) {
        c = 255;
        tblue.setText("255");
    }
    message.setText(" work submitted by:"); // text
    message.setForeground(new Color(a, b, c)); // changes colour to
                                                        // desired input

} catch (NumberFormatException ex) {

    message.setText("invalid input! please enter numbers only"); // text
    message.setForeground(new Color(0, 0, 0)); // original text set to
                                                // red
    tred.setText("");
    tgreen.setText("");
    tblue.setText(""); // clears box if not an integer
}

Answer 1

You can separate the try-catch block into 3 parts:

int a = -1;
try {
    a = Integer.parseInt(theApp.tred.getText());
    if (a < 0) {
        a = 200; 
        tred.setText("200");
    }
    if (a > 255) {
        a = 255;
        tred.setText("255");
    }
    //do the needed things here
} catch (Exception e) {
    message.setText("invalid input! please enter numbers only"); // text
    message.setForeground(new Color(0, 0, 0)); 
    tred.setText("");
}

(this is just for tred, the others are pretty much the same).