testjformattedtextfield2.java

疯狂Java讲义_源码(含Java设计模式CHM

import java.awt.*;
import java.awt.event.*;
import java.lang.reflect.*;
import java.net.*;
import java.text.*;
import java.util.*;
import javax.swing.*;
import javax.swing.text.*;
import javax.swing.border.*;


/**
 * Description:
 * <br/>Copyright (C), 2005-2008, Yeeku.H.Lee
 * <br/>This program is protected by copyright laws.
 * <br/>Program Name:
 * <br/>Date:
 * @author  Yeeku.H.Lee [e-mail]
 * @version  1.0
 */
public class TestJFormattedTextField2
{
	private JFrame mainWin = new JFrame("测试格式化文本框");
	private JButton okButton = new JButton("确定");
	//定义用于添加格式化文本框的容器
	private JPanel mainPanel = new JPanel();

	public void init()
	{
		//添加按钮
		JPanel buttonPanel = new JPanel();
		buttonPanel.add(okButton);

		mainPanel.setLayout(new GridLayout(0, 3));
		mainWin.add(mainPanel, BorderLayout.CENTER);


		JFormattedTextField intField0 = new JFormattedTextField(
			new InternationalFormatter(NumberFormat.getIntegerInstance())
			{
				protected DocumentFilter getDocumentFilter()
				{
					return new NumberFilter();
				}
			});
		intField0.setValue(100);                     
		addRow("只接受数字的文本框", intField0);

		JFormattedTextField intField1 = new JFormattedTextField(NumberFormat.getIntegerInstance());
		intField1.setValue(new Integer(100));
		//添加输入校验器
		intField1.setInputVerifier(new FormattedTextFieldVerifier());
		addRow("带输入校验器的文本框", intField1);

		//创建自定义格式器对象
		IPAddressFormatter ipFormatter = new IPAddressFormatter();
		ipFormatter.setOverwriteMode(false);
		//以自定义格式器对象创建格式化文本框
		JFormattedTextField ipField = new JFormattedTextField(ipFormatter);
		ipField.setValue(new byte[] { (byte)192, (byte)168, 4, 1 });
		addRow("IP地址格式", ipField);
 
		
		mainWin.add(buttonPanel , BorderLayout.SOUTH);
		mainWin.pack();
		mainWin.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		mainWin.setVisible(true);
	}
	//定义添加一行格式化文本框的方法
	private void addRow(String labelText, final JFormattedTextField field)
	{
		mainPanel.add(new JLabel(labelText));
		mainPanel.add(field);
		final JLabel valueLabel = new JLabel();
		mainPanel.add(valueLabel);
		//为"确定"按钮添加事件监听器
		//当用户单击“确定”按钮时，文本框后显示文本框内的值
		okButton.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent event)
			{
				Object value = field.getValue();
				//如果该值是数组，使用Arrays的toString方法输出数组
				if (value.getClass().isArray())
				{ 
                  StringBuilder builder = new StringBuilder();
                  builder.append('{');
                  for (int i = 0; i < Array.getLength(value); i++)
                  {
                     if (i > 0) builder.append(',');
                     builder.append(Array.get(value, i).toString());
                  }
                  builder.append('}');
                  valueLabel.setText(builder.toString());
				}
				else
				{
					//输出格式化文本框的值
					valueLabel.setText(value.toString());
				}
			}
		});
	}

	public static void main(String[] args) 
	{
		new TestJFormattedTextField2().init();
	}
}
//输入校验器
class FormattedTextFieldVerifier extends InputVerifier 
{
	//当输入组件失去焦点时，该方法被触发
	public boolean verify(JComponent component) 
	{
		JFormattedTextField field = (JFormattedTextField) component;
		//返回用户输入是否有效
		return field.isEditValid();
	}
}
//数字过滤器
class NumberFilter extends DocumentFilter
{
	public void insertString(FilterBypass fb, int offset, String string,
		AttributeSet attr)throws BadLocationException 
	{
		StringBuilder builder = new StringBuilder(string);
		//过滤用户输入的所有字符
		filterInt(builder);
		super.insertString(fb, offset, builder.toString(), attr);
	}

	public void replace(FilterBypass fb, int offset, int length, String string, 
		AttributeSet attr)throws BadLocationException 
	{
		if (string != null) 
		{
			StringBuilder builder = new StringBuilder(string);
			//过滤用户替换的所有字符
			filterInt(builder);
			string = builder.toString();
		}
		super.replace(fb, offset, length, string, attr);
	}
	//过滤整数字符，把所有非0～9的字符全部删除
	private void filterInt(StringBuilder builder)
	{
		for (int i = builder.length() - 1; i >= 0; i--)
		{
			int cp = builder.codePointAt(i);
			if (cp > '9' || cp < '0') 
			{
				builder.deleteCharAt(i);
			}
		}
	}
}


class IPAddressFormatter extends DefaultFormatter
{
	public String valueToString(Object value) 
		throws ParseException
	{
		if (!(value instanceof byte[])) 
		{
			throw new ParseException("该IP地址的值只能是字节数组", 0);
		}
		byte[] a = (byte[])value;
		if (a.length != 4) 
		{
			throw new ParseException("IP地址必须是四个整数", 0);
		}
		StringBuilder builder = new StringBuilder();
		for (int i = 0; i < 4; i++)
		{
			int b = a[i];
			if (b < 0) b += 256;
			builder.append(String.valueOf(b));
			if (i < 3) builder.append('.');
		}
		return builder.toString();
	}

	public Object stringToValue(String text) throws ParseException
	{
		//将格式化文本框内的字符串以点号（.）分成四节。
		String[] nums = text.split("\\.");
		if (nums.length != 4)
		{
			throw new ParseException("IP地址必须是四个整数", 0);
		}
		byte[] a = new byte[4];
		for (int i = 0; i < 4; i++)
		{

			int b = 0;
			try
			{
				b = Integer.parseInt(nums[i]);
			}
			catch (NumberFormatException e)
			{
				throw new ParseException("IP地址必须是整数", 0);
			}
			if (b < 0 || b >= 256) 
			{
				throw new ParseException("IP地址值只能在0~255之间", 0);
			}
			a[i] = (byte) b;
		}
		return a;
	}
}