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javaswingjtextfielddocumentfilter

set jtextfield textlimit and uppercase at same time


I Have a couple jtextfield in my app and I want to put one of them that allow upper and lowcase and also put the limit of number of character that can be introduce into the jtextfield. I have to separe class, one to put the limit and the other to put the upper or lowcase.

code to the limit of jtextfield:

package tester;

import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.PlainDocument;

public class TextLimiter extends PlainDocument {

    private Integer limit;

    public TextLimiter(Integer limit) {
        super();
        this.limit = limit;
    }

    public void insertString(int offs, String str, AttributeSet a) throws BadLocationException {
        if (str == null) {
            return;
        }
        if (limit == null || limit < 1 || ((getLength() + str.length()) <= limit)) {
            super.insertString(offs, str, a);
        } else if ((getLength() + str.length()) > limit) {
            String insertsub = str.substring(0, (limit - getLength()));
            super.insertString(offs, insertsub, a);
        }
    }
}

and here is the code to set uppercase or vice versa:

package classes;

import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.DocumentFilter;

public class upperCASEJTEXTFIELD extends DocumentFilter {

    @Override
    public void insertString(DocumentFilter.FilterBypass fb, int offset, String text,
            AttributeSet attr) throws BadLocationException {
        fb.insertString(offset, text.toUpperCase(), attr);
    }

    @Override
    public void replace(DocumentFilter.FilterBypass fb, int offset, int length, String text,
            AttributeSet attrs) throws BadLocationException {

        fb.replace(offset, length, text.toUpperCase(), attrs);
    }
}

to resume my question, I want to set a jtextfield limit = 11 and uppercase.


Solution

  • PlainDocument doc = new TextLimiter();
    doc.setDocumentFiletr(new upperCASEJTEXTFIELD());
    JTextField textField = new JTextField();
    textField.setDocument(doc);