限制jtextfield上的特定字符

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

class CustomDocumentFilter extends DocumentFilter {
    @Override
    public void insertString(DocumentFilter.FilterBypass fb, int offset, String text, AttributeSet attr) throws BadLocationException {
        // 检查插入的文本是否是我们允许的类型
        if (text.matches("[0-9]+")) {
            super.insertString(fb, offset, text, attr);
        }
    }

    @Override
    public void replace(DocumentFilter.FilterBypass fb, int offset, int length, String text, AttributeSet attrs) throws BadLocationException {
        if (text.matches("[0-9]+")) {
            super.replace(fb, offset, length, text, attrs);
        }
    }
}

// 在 JTextField 中应用 DocumentFilter
JTextField textField = new JTextField();
AbstractDocument document = (AbstractDocument) textField.getDocument();
document.setDocumentFilter(new CustomDocumentFilter());

import javax.swing.*;
import java.awt.*;

class CustomInputVerifier extends InputVerifier {
    @Override
    public boolean verify(JComponent input) {
        JTextField textField = (JTextField) input;
        String text = textField.getText();
        
        // 检查文本是否是我们允许的类型
        return text.matches("[0-9]+");
    }
}

// 在 JTextField 中应用 InputVerifier
JTextField textField = new JTextField();
textField.setInputVerifier(new CustomInputVerifier());