notepad.java

一个记事本程序

		flow.setAlignment(FlowLayout.RIGHT);
		statusBar = new JPanel();
		statusBar.setLayout(flow);
		tfStatus = new JTextField("这是状态栏，还未处理好，见谅!",20);
		tfStatus.setEditable(false);
		statusBar.add(tfStatus);
		add(statusBar,BorderLayout.SOUTH);
		statusBar.setVisible(false);
		//状态栏完毕
		/** ***********添加事件监听*********** */
		// ----文件菜单
		build.addActionListener(this); // OK
		open.addActionListener(this); // OK
		save.addActionListener(this); // OK
		reSave.addActionListener(this); // OK
		setPage.addActionListener(this);
		print.addActionListener(this);
		quit.addActionListener(this); // OK
		// ----编辑菜单
		retract.addActionListener(this);// mostly OK
		cut.addActionListener(this); // OK
		copy.addActionListener(this); // OK
		paste.addActionListener(this); // OK
		delete.addActionListener(this); // OK
		find.addActionListener(this); // OK
		findNext.addActionListener(this); // OK
		replace.addActionListener(this); // OK
		goTo.addActionListener(this); // not compeleted
		selectAll.addActionListener(this); // OK
		dateAndTime.addActionListener(this); // OK
		// ----格式菜单
		wrap.addActionListener(this); // OK
		font.addActionListener(this); // OK
		// ----查看菜单
		status.addActionListener(this); // not compeleted
		// ----帮助菜单
		title.addActionListener(this);
		about.addActionListener(this);
		// 右键菜单
		popRetract.addActionListener(this);
		popCut.addActionListener(this); // OK
		popCopy.addActionListener(this); // OK
		popPaste.addActionListener(this); // OK
		popDelete.addActionListener(this); // OK
		popSelectAll.addActionListener(this); // OK
	}

	/**
	 * 转到文档中相应的行
	 * 
	 * @param line
	 *            待转到行号
	 * @return 跳转成功返回true，否则返回false
	 */
	public boolean goTo(int line) {
		int documentLine = note.getLineCount();
		if (line > documentLine)
			return false;
		else {
			note.setCaretPosition(line);
			return true;
		}

	}

	/**
	 * 将文件加载到记事本中
	 * 
	 * @param file
	 *            要加载的文件对象
	 */
	public void readFile(File file) {
		try {
			FileReader readIn = new FileReader(file);
			int size = (int) file.length();
			int charsRead = 0;
			char content[] = new char[size];
			while (readIn.ready()) {
				charsRead += readIn.read(content, charsRead, size - charsRead);
			}
			readIn.close();
			String fileContent = new String(content, 0, charsRead);
			hashCode = fileContent.hashCode();
			note.setText(fileContent);
		} catch (IOException ee) {
		}
	}

	/**
	 * 将记事本中的文本写入文件中
	 * 
	 * @param file
	 *            要写入的文件对象
	 */
	public void writeFile(File file) {
		try {
			FileWriter writeFile = new FileWriter(file);
			writeFile.write(note.getText());
			writeFile.close();
		} catch (IOException eeee) {
		}
	}

	/**
	 * 用replaceTo替换文档中全部的key
	 * 
	 * @param key
	 *            被替换的关键字
	 * @param replaceTo
	 *            被替换成的文字
	 * @param ignoreCase
	 *            是否忽略大小写
	 * @return 替换成功返回true，否则返回false
	 */
	public void replaceAll(String key, String replaceTo, boolean ignoreCase) {
		boolean hasKey = false;
		String content = note.getText();
		int contentLength = content.length();
		int keyLength = key.length();
		String first = String.valueOf(key.charAt(0));
		// 先搜索看看是否存在key在文档中
		for (int i = mileStone; i < contentLength; i++) {
			String temp = String.valueOf(content.charAt(i));
			if (ignoreCase) {
				if (first.equalsIgnoreCase(temp)) {
					temp = content.substring(i, i + keyLength);
					if (temp.equalsIgnoreCase(key)) {
						hasKey = true;
						break;
					}
				}
			} else {
				if (first.equals(temp)) {
					temp = content.substring(i, i + keyLength);
					if (temp.equals(key)) {
						hasKey = true;
						break;
					}
				}
			}
		}
		if (!hasKey) {
			JOptionPane.showMessageDialog(null, "找不到关键字 \"" + key + "\"");
		} else {
			for (int i = 0; i < contentLength; i++) {
				if (!OnFindMenuItem(key, ignoreCase)) {
					return;
				} else {
					note.replaceSelection(replaceTo);
				}
			}
		}
	}

	/**
	 * 处理 ‘替换’ 菜单项中查找工作的函数
	 * 
	 * @param key
	 *            要查找的关键字
	 * @param ignoreCase
	 *            是否忽略大小写
	 * @return 如果没找到该关键字，返回false，否则返回true
	 */
	public boolean OnFindMenuItem(String key, boolean ignoreCase) {
		String content = note.getText();
		int contentLength = content.length();
		int keyLength = key.length();
		String first = String.valueOf(key.charAt(0));
		for (int i = mileStone; i < contentLength; i++) {
			String temp = String.valueOf(content.charAt(i));
			if (ignoreCase) {
				if (first.equalsIgnoreCase(temp)) {
					temp = content.substring(i, i + keyLength);
					if (temp.equalsIgnoreCase(key)) {
						note.select(i, i + keyLength);
						mileStone = i + 1;
						return true;
					}
				}
			} else {
				if (first.equals(temp)) {
					temp = content.substring(i, i + keyLength);
					if (temp.equals(key)) {
						note.select(i, i + keyLength);
						mileStone = i + 1;
						return true;
					}
				}
			}
		}
		return false;
	}

	/**
	 * 处理 ‘查找’ 菜单项中查找工作的函数
	 * 
	 * @param key
	 *            查找的关键字
	 * @param ignoreCase
	 *            是否忽略大小写
	 * @param isUp
	 *            是否从下到上查找
	 * @return 如果没找到该关键字，返回false，否则返回true
	 */
	public boolean OnFindMenuItem(String key, boolean ignoreCase, boolean isUp) {
		String content = note.getText();
		int contentLength = content.length();
		int keyLength = key.length();
		int caretPosition = note.getCaretPosition();
		if (!isUp) {// 向下搜索
			String first = String.valueOf(key.charAt(0));
			for (int i = caretPosition; i < contentLength; i++) {
				String temp = String.valueOf(content.charAt(i));
				if (ignoreCase) {
					if (first.equalsIgnoreCase(temp)) {
						temp = content.substring(i, i + keyLength);
						if (temp.equalsIgnoreCase(key)) {
							note.select(i, i + keyLength);
							return true;
						}
					}
				} else {
					if (first.equals(temp)) {
						temp = content.substring(i, i + keyLength);
						if (temp.equals(key)) {
							note.select(i, i + keyLength);
							return true;
						}
					}
				}
			}
		} else {// 向上搜索
			String last = String.valueOf(key.charAt(keyLength - 1));
			// 查找对话框出现之后 第一次 调用本函数
			if (isFirstCall) {
				for (int i = caretPosition - 1; i > 0; i--) {
					String temp = String.valueOf(content.charAt(i));
					if (ignoreCase) {
						if (last.equalsIgnoreCase(temp)) {
							temp = content.substring(i - keyLength + 1, i + 1);
							if (temp.equalsIgnoreCase(key)) {
								mileStone = i - 1;
								isFirstCall = false;
								note.select(i - keyLength + 1, i + 1);
								return true;
							}
						}
					} else {
						if (last.equals(temp)) {
							temp = content.substring(i - keyLength + 1, i + 1);
							if (temp.equals(key)) {
								mileStone = i - 1;
								isFirstCall = false;
								note.select(i - keyLength + 1, i + 1);
								return true;
							}
						}
					}
				}
			}
			// 查找对话框出现之后不是 第一次 调用本函数
			else {
				for (int i = mileStone; i > 0; i--) {
					String temp = String.valueOf(content.charAt(i));
					if (ignoreCase) {
						if (last.equalsIgnoreCase(temp)) {
							temp = content.substring(i - keyLength + 1, i + 1);
							if (temp.equalsIgnoreCase(key)) {
								mileStone = i - 1;
								isFirstCall = false;
								note.select(i - keyLength + 1, i + 1);
								return true;
							}
						}
					} else {
						if (last.equals(temp)) {
							temp = content.substring(i - keyLength + 1, i + 1);
							if (temp.equals(key)) {
								mileStone = i - 1;
								isFirstCall = false;
								note.select(i - keyLength + 1, i + 1);
								return true;
							}
						}
					}
				}
			}
		}
		return false;
	}

	/**
	 * 菜单栏事件处理函数
	 */
	public void actionPerformed(ActionEvent e) {
		/** ***新建文件*****OK */
		if (e.getSource() == build) {
			// 打开的文件
			if (isTitled) {
				int newHashCode = 0;
				String fileContent = note.getText();
				newHashCode = fileContent.hashCode();
				// 如果文件内容被修改了，新建文件之前询问是否保存文件
				if (hashCode != newHashCode) {
					int isExit = JOptionPane.showConfirmDialog(null, "文件 "
							+ filePath + " 的文字已经改变，想保存文件吗 ?", "记事本",
							JOptionPane.YES_NO_CANCEL_OPTION);
					if (isExit == JOptionPane.YES_OPTION) {

						File file = new File(filePath);
						writeFile(file);
						note.setText("");
						isTitled = false;
						fileName = "无标题";
						filePath = null;
						setTitle(fileName + "-记事本");

					} else if (isExit == JOptionPane.NO_OPTION) {
						note.setText("");
						isTitled = false;
						fileName = "无标题";
						setTitle(fileName + "-记事本");
					} else
						return;
				}
				// 打开的文件，而且文件内容没有被修改，直接新建
				else {
					note.setText("");