fnumberfield.java

Java数字输入控件。只能够输入0－9的数字

package com.utstar.ems.omcs.function;

import javax.swing.*;
import javax.swing.text.*;

import java.awt.Toolkit;
import java.text.NumberFormat;
import java.text.ParseException;
import java.util.Locale;

/**
 * <p>Title: number</p>
 * <p>Description: this textField only accept numbers, you can set max number and max column too.</p>
 * <p>Copyright: Copyright (c) 2004</p>
 * <p>Company: </p>
 * @author not attributable
 * @version 1.0
 */

public class FNumberField extends JTextField
{
    private Toolkit toolkit;
    private NumberFormat integerFormatter;
    private int maxValue = Integer.MAX_VALUE;

    // default
    public FNumberField()
    {
        super();
        toolkit = Toolkit.getDefaultToolkit();
        integerFormatter = NumberFormat.getNumberInstance(Locale.US);
        integerFormatter.setParseIntegerOnly(true);
    }

    // number of bits
    public FNumberField(int columns)
    {
        super(columns);
        toolkit = Toolkit.getDefaultToolkit();
        integerFormatter = NumberFormat.getNumberInstance(Locale.US);
        integerFormatter.setParseIntegerOnly(true);
    }

    // initail value and number of bits
    public FNumberField(int value, int columns)
    {
        super(columns);
        toolkit = Toolkit.getDefaultToolkit();
        integerFormatter = NumberFormat.getNumberInstance(Locale.US);
        integerFormatter.setParseIntegerOnly(true);
        setValue(value);
    }

    public int getValue()
    {
        int retVal = 0;
        try
        {
            retVal = integerFormatter.parse(getText()).intValue();
        }
        catch (ParseException e)
        {
            toolkit.beep();
        }
        return retVal;
    }

    public void setValue(int value)
    {
        setText(integerFormatter.format(value));
    }

    protected Document createDefaultModel()
    {
        return new TNumberDocument();
    }

    public void setMaxValue(int max)
    {
        maxValue = max;
    }

    protected class TNumberDocument extends PlainDocument
    {
        public void remove(int offs, int len) throws BadLocationException
        {
            super.remove(offs, len);
            String newStr = FNumberField.this.getText();
            for (int i = 0; i < newStr.length() - 1; i++)
            {
                if (newStr.charAt(i) != '0')
                {
                    break;
                }
                super.remove(0, 1);
            }
        }

        public void insertString(int offs, String str, AttributeSet a) throws BadLocationException
        {
            char[] source = str.toCharArray();
            char[] result = new char[source.length];
            int j = 0;
            String temp = FNumberField.this.getText();
            if (str.equals(""))
            {
            }
            else
            {
                for (int i = 0; i < result.length; i++)
                {
                    if (Character.isDigit(source[i]))
                    {
                        result[j++] = source[i];
                    }
                    else
                    {
                        toolkit.beep();
                    }
                }
            }

            StringBuffer buffer = new StringBuffer(FNumberField.this.getText());
            buffer.insert(offs, result, 0, j);
            int newValue = 0;
            if (!buffer.toString().equals(""))
            {
                try
                {
                    newValue = Integer.parseInt(buffer.toString());
                }
                catch (Exception ex)
                {
                    newValue = maxValue;
                }
            }

            if (newValue < maxValue)
            {
                super.insertString(offs, new String(result, 0, j), a);
            }

            String newStr = FNumberField.this.getText();
            for (int i = 0; i < newStr.length() - 1; i++)
            {
                if (newStr.charAt(i) != '0')
                {
                    break;
                }
                super.remove(0, 1);
            }
        }
    }
}