notepad.java

本程序讲述的是一个记事本程序,大大多多下载1

import java.awt.*;
import java.awt.event.WindowListener;
import java.awt.event.*;
import java.util.EventListener;
import java.io.*;
import javax.imageio.*;
import javax.swing.JOptionPane;
import java.lang.Object.*;
import javax.swing.*;
import java.awt.datatransfer.*;
public class Notepad
{
	public static void main(String[] args)
	{
		final JFrame f = new JFrame("记事本");
		
		f.setDefaultCloseOperation(WindowConstants.DO_NOTHING_ON_CLOSE);
		
		f.setSize(600,400);
		f.setLocation(200,200);
		//final TextArea ta = new TextArea();
		final JTextArea ta = new JTextArea();	
		//System.out.println(ta.getLineWrap());
		//ta.setWrapStyleWord(true);
		//ta.setLineWrap(true);
		//ta.setWrapStyleWord(true);
		JScrollPane jp = new JScrollPane(ta);
		//设置滚动条可见
		jp.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_ALWAYS );
		jp.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS );
		//System.out.println(ta.getWrapStyleWord());
		ta.setBackground(Color.white);
		f.add(jp);
		JMenuBar mb = new JMenuBar();
		JMenu m1 = new JMenu("文件");
		JMenu m2 = new JMenu("编辑");
		JMenu m3= new JMenu("帮助");
		JMenuItem mi1 = new JMenuItem("新建");
		JMenuItem mi2 = new JMenuItem("打开");
		mi2.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{
				FileDialog fd = new FileDialog(f,"打开",FileDialog.LOAD);
				fd.show();
				String strFile = fd.getDirectory()+fd.getFile();
				if(strFile!=null)
				{
					try
					{
						FileInputStream fis = new FileInputStream(strFile);
						int r = 0;
						StringBuffer sb = new StringBuffer();
						while (r != -1) 
						{
							byte[] buf = new byte[1024];
							r = fis.read(buf);
							if (r != -1) 
							{
								sb.append(new String(buf, 0, r));
							}
						}
						ta.append(new String(sb));
						//System.out.println(ta.getLineCount());
						fis.close();
					}
					catch(Exception ex)
					{
		//				ex.printStackTrace();
					}
				}
				//fd.show();
			}
		});
		JMenuItem mi3 = new JMenuItem("保存");
		mi3.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{				
				FileDialog fd = new FileDialog(f,"保存",FileDialog.SAVE);
				fd.show();
				String strFile = fd.getDirectory()+fd.getFile();
				try
				{
					BufferedWriter bw = new BufferedWriter(new FileWriter(strFile));
					bw.write(ta.getText());
					bw.flush();
					bw.close();
				}
				catch(Exception ex)
				{
					ex.printStackTrace();
				}
			}
		});
		JMenuItem mi4 = new JMenuItem("另存为");
		mi4.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{				
				FileDialog fd = new FileDialog(f,"保存",FileDialog.SAVE);
				fd.show();
				String strFile = fd.getDirectory()+fd.getFile();
				try
				{
					BufferedWriter bw = new BufferedWriter(new FileWriter(strFile));
					bw.write(ta.getText());
					bw.flush();
					bw.close();
				}
				catch(Exception ex)
				{
					ex.printStackTrace();
				}
			}
		});
		JMenuItem mi5 = new JMenuItem("退出");
		mi5.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{
				if(!ta.getText().equals(""))
				{
					int d = JOptionPane.showConfirmDialog(f,
			 		"记事本的文字已经改变想保存文件吗？",
			 		"记事本",JOptionPane.YES_NO_CANCEL_OPTION, 
			 		JOptionPane.INFORMATION_MESSAGE);
      		 		if(d == JOptionPane.YES_OPTION)
      		 		{
      		 			FileDialog fd = new FileDialog(f,"保存",FileDialog.SAVE);
						fd.show();
						String strFile = fd.getDirectory()+fd.getFile();
						try
						{
							BufferedWriter bw = new BufferedWriter(new FileWriter(strFile));
							bw.write(ta.getText());
							bw.flush();
							bw.close();
						}
						catch(Exception ex)
						{
							ex.printStackTrace();
						}
      		 		}
      		 		if(d == JOptionPane.NO_OPTION)
			 		{
			 			System.exit(0);
			 		}
			 		else if(d == JOptionPane.CANCEL_OPTION )
			 		{
			 		}	
				}
				else
				{
					System.exit(0);
				}
			}
		});
		JMenuItem mi61 = new JMenuItem("自动换行");
		class ItActionListener1 implements ActionListener
		{
			public void actionPerformed(ActionEvent e)
			{
				ta.setLineWrap(true);
				ta.setWrapStyleWord(true);
			}
		} 
		mi61.addActionListener(new ItActionListener1());
		JMenuItem mi71 = new JMenuItem("剪切");
		mi71.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{
				try
				{
					Clipboard cb = Toolkit.getDefaultToolkit().getSystemClipboard();
					cb.setContents(new StringSelection(ta.getSelectedText()),null);
					ta.replaceRange("",ta.getSelectionStart(),ta.getSelectionEnd());
				}
				catch(Exception ex)
				{
					ex.printStackTrace();
				}				
			}
		});
		JMenuItem mi81 = new JMenuItem("复制");
		mi81.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{
				try
				{
					Clipboard cb = Toolkit.getDefaultToolkit().getSystemClipboard();
					cb.setContents(new StringSelection(ta.getSelectedText()),null);
				}
				catch(Exception ex)
				{
					ex.printStackTrace();
				}				
			}
		});
		JMenuItem mi91 = new JMenuItem("粘贴");
		mi91.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{
				try
				{
					Clipboard cb = Toolkit.getDefaultToolkit().getSystemClipboard();
					Transferable content = cb.getContents(null);
					ta.replaceRange((String)content.getTransferData(DataFlavor.stringFlavor),
					ta.getSelectionStart(),ta.getSelectionEnd());
				}
				catch(Exception ex)
				{
					ex.printStackTrace();
				}
			}
		});
		JMenuItem mi101 = new JMenuItem("删除");
		mi101.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{
				try
				{
					ta.replaceRange("",ta.getSelectionStart(),ta.getSelectionEnd());	
				}
				catch(Exception ex)
				{
					ex.printStackTrace();
				}
			}
		});
		JMenuItem mi111 = new JMenuItem("查找");
		mi111.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{
				final JDialog jd = new JDialog(f,"查找");
				jd.setSize(350,120);
				jd.setLocation(350,300);
				JLabel jl = new JLabel("查找内容");
				final JTextField tf = new JTextField(20);
				JButton jb1 = new JButton("查找");
				JButton jb2 = new JButton("取消"); 
				GridBagLayout gb = new GridBagLayout();
         		GridBagConstraints c = new GridBagConstraints();
         		jd.setLayout(gb);
         		c.weightx = 60;
         		c.weighty = 30;
         		c.gridwidth = GridBagConstraints.RELATIVE;
         		gb.setConstraints(jl,c);
         		c.gridwidth = GridBagConstraints.REMAINDER;
         		gb.setConstraints(tf,c);
         		c.weightx = 5;
         		c.gridx = 1;
         		c.gridwidth = GridBagConstraints.RELATIVE;
         		gb.setConstraints(jb1,c);
         		c.gridx = 3;
         		c.gridx = GridBagConstraints.RELATIVE;     			    	
         		gb.setConstraints(jb2,c);  
         	//	c.gridwidth = GridBagConstraints.REMAINDER;       		 
				jd.add(jl);
				jd.add(tf);
				jd.add(jb1);
				jd.add(jb2);
				jd.setResizable(false);
				jd.show();
				jb1.addActionListener(new ActionListener()
				{
					public void actionPerformed(ActionEvent ae)
					{
						try
						{
							String str1 = tf.getText();
							int len = str1.length();
							String text = ta.getText();
							int sum = text.length();
							int start = ta.getSelectionEnd();
							if(start ==sum)
							start = 0;
							for(;len<=sum&&start<=sum-len;start++)
							{
								if(start ==sum)
								start = 0;
								if(text.substring(start,start+len).equals(str1))
								{
									ta.setSelectionStart(start);
									ta.setSelectionEnd(start+len);
									return;
								}
							}
							JOptionPane.showMessageDialog(null,"所指定的文本没有找到",
							"记事本",JOptionPane.INFORMATION_MESSAGE);			
						}
						catch(Exception ex)
						{	
							ex.printStackTrace();
						}	
					}
				});
				jb2.addActionListener(new ActionListener()
				{
					public void actionPerformed(ActionEvent e)
					{
						try
						{
							jd.dispose();
						}
						catch(Exception ex)
						{
							ex.printStackTrace();
						}
					}
				});			
			}
		});
		JMenuItem mi121 = new JMenuItem("替换");
		mi121.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{
				final JDialog jd = new JDialog(f,"替换");
				jd.setSize(350,120);
				jd.setLocation(350,300);
				JLabel jl1 = new JLabel("查找内容");
				final JTextField tf1 = new JTextField(20);
				JLabel jl2 = new JLabel("替换为");
				final JTextField tf2 = new JTextField(20);
				JButton jb1 = new JButton("替换");
				JButton jb2 = new JButton("取消"); 
				GridBagLayout gb = new GridBagLayout();
         		GridBagConstraints c = new GridBagConstraints();
         		jd.setLayout(gb);
         		c.weightx = 60;
         		c.weighty = 30;
         		c.gridwidth = GridBagConstraints.RELATIVE;
         		gb.setConstraints(jl1,c);
         		c.gridwidth = GridBagConstraints.REMAINDER;
         		gb.setConstraints(tf1,c);
         		c.gridwidth = GridBagConstraints.RELATIVE;
         		gb.setConstraints(jl2,c);
         		c.gridwidth = GridBagConstraints.REMAINDER;
         		gb.setConstraints(tf2,c);
         		c.weightx = 5;
         		c.gridx = 1;
         		c.gridwidth = GridBagConstraints.RELATIVE;
         		gb.setConstraints(jb1,c);
         		c.gridx = 3;
         		c.gridx = GridBagConstraints.RELATIVE;     			    	
         		gb.setConstraints(jb2,c);     		 
				jd.add(jl1);
				jd.add(tf1);
				jd.add(jl2);
				jd.add(tf2);
				jd.add(jb1);
				jd.add(jb2);
				jd.setResizable(false);
				jd.show();
				jb1.addActionListener(new ActionListener()
				{
					public void actionPerformed(ActionEvent ae)
					{
						try
						{
							String str1 = tf1.getText();
							int len = str1.length();
							String str2 = tf2.getText();
							String text = ta.getText();
							int sum = text.length();
							int start = ta.getSelectionEnd();
							if(start ==sum)
							start = 0;
							for(;len<=sum&&start<=sum-len;start++)
							{
								if(text.substring(start,start+len).equals(str1))
								{
									ta.replaceRange(str2,start,(start+len));
									return;
								}
							}
							JOptionPane.showMessageDialog(null,"所指定的文本没有找到,无法替换",
							"记事本",JOptionPane.INFORMATION_MESSAGE);			
						}
						catch(Exception ex)
						{	
							ex.printStackTrace();
						}	
					}
				});
				jb2.addActionListener(new ActionListener()
				{
					public void actionPerformed(ActionEvent e)
					{
						try
						{
							jd.dispose();
						}
						catch(Exception ex)
						{
							ex.printStackTrace();
						}
					}
				});			
			}
		});
		JMenuItem mi131 = new JMenuItem("全选");
		mi131.addActionListener(new ActionListener()
		{
			public void actionPerformed(ActionEvent e)
			{
				try
				{
					String text = ta.getText();
					int len = text.length();
					ta.selectAll();
				}
				catch(Exception ex)
				{