mymenubar.java

用JAVA语言实现的计算器小程序.如果安装了JVM可以直接运行NotePad.jar文件,已经调试通过的源代码.

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.awt.datatransfer.*;

public class MyMenuBar extends MenuBar{//菜单栏，主要是对MenuBar的应用
public MyMenuBar(Frame parent){
	parent.setMenuBar(this);
    }
public void addMenu(String[]menus){//添加菜单
	for(int i=0;i<menus.length;i++)
		add(new Menu(menus[i]));
    }
public void addMenuItems(int menuNumber,String[]items){//添加菜单中的子项菜单或分隔符
	for(int i=0;i<items.length;i++){
		if(items[i]!=null)
			getMenu(menuNumber).add(new MenuItem(items[i]));
		else
			getMenu(menuNumber).addSeparator();
	       }	
      }
public void addActionListener(ActionListener al){
	for(int i=0;i<getMenuCount();i++)
		for(int j=0;j<getMenu(i).getItemCount();j++)		
			getMenu(i).getItem(j).addActionListener(al);

      }
}


class MyFile{//对文件进行操作，打开或者保存，主要是对Dialog的应用	
	private FileDialog fDlg;
	public MyFile(Frame parent){
	   fDlg=new FileDialog(parent,"",FileDialog.LOAD);
	}
	private String getPath(){//获得打开文件的路径
		return fDlg.getDirectory()+"\\"+fDlg.getFile();
	}
	public String getData()throws Exception{//读取打开文件的内容	
		fDlg.setTitle("打开");
		fDlg.setMode(FileDialog.LOAD);
		fDlg.setVisible(true);
		BufferedReader br=new BufferedReader(new FileReader(getPath()));
		StringBuffer sb=new StringBuffer();
		String aline;
		while((aline=br.readLine())!=null)
			sb.append(aline+'\n');
		br.close();
		return sb.toString();	
	   
	}
	public void setData(String data)throws Exception{//保存文件
		fDlg.setTitle("保存");
		fDlg.setMode(FileDialog.SAVE);
		fDlg.setVisible(true);
		BufferedWriter bw=new BufferedWriter(new FileWriter(getPath()));
		bw.write(data);
		bw.close();
	}

}


class MyClipboard{//剪贴板的应用
	private Clipboard cb;
	public MyClipboard(){
		cb=Toolkit.getDefaultToolkit().getSystemClipboard();		
	}
	public void setData(String data){//内容暂存于剪贴板
		cb.setContents(new StringSelection(data),null);
	}
	public String getData(){//获取剪贴板的内容
		Transferable content=cb.getContents(null);
		try{
			return (String)content.getTransferData(DataFlavor.stringFlavor);
		}catch(Exception exp){}
		return null;
	}
}

class MyFindDialog extends Dialog implements ActionListener{//为查找和替换设计框架，并且实现相应的功能
	private Label lFind=new Label("查找字符串");
	private Label lReplace=new Label("替换字符串");
	private TextField tFind=new TextField(10);
	private TextField tReplace=new TextField(10);
	private Button bFind=new Button("查找");
	private Button bReplace=new Button("替换");
	private TextArea ta;
	public MyFindDialog(Frame owner,TextArea ta){
		super(owner,"查找",false);
		this.ta=ta;
		//完成控件的布局，同时有关的其他设计
		setLayout(null);
		lFind.setBounds(10,30,80,20);
		lReplace.setBounds(10,70,80,20);
		tFind.setBounds(90,30,90,20);
		tReplace.setBounds(90,70,90,20);
		bFind.setBounds(190,30,80,20);
		bReplace.setBounds(190,70,80,20);
		add(lFind);add(tFind);add(bFind);add(lReplace);
		add(tReplace);add(bReplace);
		setResizable(false);
		bFind.addActionListener(this);
		bReplace.addActionListener(this);
		addWindowListener(new WindowAdapter(){
			public void windowClosing(WindowEvent e){
				MyFindDialog.this.dispose();
			}
		});		
	}
	public void showFind(){
		setTitle("查找");setSize(280,60);setVisible(true);
	}
	public void showReplace(){
		setTitle("查找替换");setSize(280,60);setVisible(true);
	}
	private void find(){//实现查找功能
		String text=ta.getText();
		String str=tFind.getText();
		int end=text.length();
		int len=str.length();
		int start=ta.getSelectionEnd();			
		if(start==end)start=0;		
		for(;start<=end-len;start++){
			if(text.substring(start,start+len).equals(str)){
		ta.setSelectionStart(start);
		ta.setSelectionEnd(start+len);
		return;
		  }
		}
		ta.setSelectionStart(end);
		ta.setSelectionEnd(end);
	}
	private void replace(){//实现替换功能
		String str=tReplace.getText();
		if(ta.getSelectedText().equals(tFind.getText()))
			ta.replaceRange(str, ta.getSelectionStart(), ta.getSelectionEnd());
		else find();
	}
	public void actionPerformed(ActionEvent e){
		if(e.getSource()==bFind)
			find();
		else
			if(e.getSource()==bReplace)
				replace();
	}
}



 class MyMemo extends Frame implements ActionListener {
	private TextArea editor=new TextArea();
	private MyFile mf=new MyFile(this);
	private MyClipboard cb=new MyClipboard();
	private MyFindDialog findDlg=new MyFindDialog(this,editor);
	public MyMemo(String tittle){
		super(tittle);
		MyMenuBar mb=new MyMenuBar(this);
		
		mb.addMenu(new String[]{"文件","编辑","查找","帮助"});
		mb.addMenuItems(0,new String[]{"新建","打开","保存",null,"退出"});
		mb.addMenuItems(1, new String[]{"剪贴","复制","粘贴","清除",null,"全选"});
		mb.addMenuItems(2, new String[]{"查找",null,"查找替换"});
		mb.addMenuItems(3, new String[]{"我的记事本"});
		add(editor);
		mb.addActionListener(this);
		addWindowListener(new WindowAdapter(){
			public void windowClosing(WindowEvent e){
				MyMemo.this.dispose();
			}
		});
		
	}
	public void actionPerformed(ActionEvent e){
		String selected=e.getActionCommand();
		if(selected.equals("新建"))
			editor.setText("");
		else
			if (selected.equals("打开")){
			try{
				editor.setText(mf.getData());				
			}catch(Exception exp){}
		}
			else 
				if(selected.equals("保存")){
					try{
						mf.setData(editor.getText());
					}catch(Exception exp){}
				}
				else
					if(selected.equals("退出")){
						dispose();
					}
					else
						if(selected.equals("剪贴")){
							cb.setData(editor.getSelectedText());
							editor.replaceRange("", editor.getSelectionStart(), editor.getSelectionEnd());						
							
						}
						else
							if(selected.equals("复制")){
								cb.setData(editor.getSelectedText());
							}
							else
								if(selected.equals("粘贴")){
									String str=cb.getData();
									editor.replaceRange(str, editor.getSelectionStart() , editor.getSelectionEnd());
								}
								else
									if(selected.equals("清除")){
										editor.replaceRange("", editor.getSelectionStart(),editor.getSelectionEnd());									
												
									}
									else
										if(selected.equals("全选")){
											editor.setSelectionStart(0);
											editor.setSelectionEnd(editor.getText().length());
										}
										else
											if(selected.equals("查找")){
												findDlg.showFind();
											}
											else
												if(selected.equals("查找替换")){
													findDlg.showReplace();
												}
	}
	public static void main(String[]args){
		MyMemo memo=new MyMemo("NotePad");
		memo.setSize(600,400);
		memo.setLocation(300,100);
		memo.setVisible(true);
	}
}