Thread: Document Listener in Java

I am working on live project I am using JAVA as front end and my-SQL as . I am getting confused while writing the Document Listener..!! I have tried various methods but none of them worked out. Please help by telling me how to write a Document Listener in Java? Thanks in advanced.

I suggest you to refer following example to write a document listener in java:

Code:

public class DocumentEventDemo ... {

    textField = new JTextField(25);
    textField.addActionListener(new MyTextActionListener());
    textField.getDocument().addDocumentListener(new MyDocumentListener());
    textField.getDocument().putProperty("name", "Text Field");

    textArea = new JTextArea();
    textArea.getDocument().addDocumentListener(new MyDocumentListener());
    textArea.getDocument().putProperty("name", "Text Area");
    ...

class MyDocumentListener implements DocumentListener {
    String newline = "\n";
 
    public void insertUpdate(DocumentEvent e) {
        updateLog(e, "inserted into");
    }
    public void removeUpdate(DocumentEvent e) {
        updateLog(e, "removed from");
    }
    public void changedUpdate(DocumentEvent e) {
    }

    public void updateLog(DocumentEvent e, String action) {
        Document doc = (Document)e.getDocument();
        int changeLength = e.getLength();
        displayArea.append(
            changeLength + " character" +
            ((changeLength == 1) ? " " : "s ") +
            action + doc.getProperty("name") + "." + newline +
            "  Text length = " + doc.getLength() + newline);
    }
}

Methods of the DocumentListener Interface are:
• changedUpdate(DocumentEvent) - when the style of some of the text in the listened-to document changes this method is called.
• insertUpdate(DocumentEvent) - when text is inserted into the listened-to document this method is called.
• removeUpdate(DocumentEvent) - when text is removed from the listened-to document this method is called.[/QUOTE]

Have you tried below code? If not then try this :

Code:

private static void createAndShowGUI() {

        JFrame frm = new JFrame("DocumentEventDemo");
        frm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JComponent newContent = new DocumentEventDemo();
        newContent.setOpaque(true); 
        frm.setContentPane(newContent);

        frm.pack();
        frm.setVisible(true);
    }