JavaBean实例.doc

JavaBean的编程实例：设计一个包含有一个Label和三个Button的Panel Beans（1）第一步：创建出BeanBean的程序代码import java.awt.*;import java.awt.event.*;import java.util.*;/* * 设计一个包含有一个Label和三个Button的Panel Beans*/public class YesNoPanel extends Panel / bean的属性 protected String messageText; / The message to display protected String yesLabel; / Text for the yes, no, & cancel buttons protected String noLabel; protected String cancelLabel; / Beans的内部组件 protected Button yes, no, cancel; protected Label message; /* The no-argument bean constructor, with default property values */ public YesNoPanel() this(Your Message Here); public YesNoPanel(String messageText) this(messageText, Yes, No, Cancel); public YesNoPanel(String messageText, String yesLabel, String noLabel, String cancelLabel) super();/通过调用基类的构造函数，以获得Panel的一般特性 this.messageText=messageText; / The message to display this.yesLabel=yesLabel; / Text for the yes, no, & cancel buttons this.noLabel=noLabel; this.cancelLabel=cancelLabel;this.setLayout(new BorderLayout(15, 15);/ Put the message label in the middle of the window.message = new Label(messageText);add(message, BorderLayout.CENTER);/ Create a panel for the Panel buttons and put it at the bottom/ of the Beans Panel. Specify a FlowLayout layout manager for it.Panel buttonPanel = new Panel();buttonPanel.setLayout(new FlowLayout(FlowLayout.CENTER, 25, 15);this.add(buttonPanel, BorderLayout.SOUTH);/ Create each specified button, specifying the action listener/ and action command for each, and adding them to the buttonboxyes = new Button(); / Create buttonsno = new Button();cancel = new Button();this.setYesLabel(yesLabel);this.setNoLabel(noLabel);this.setCancelLabel(cancelLabel);/ Add the buttons to the button boxbuttonPanel.add(yes);buttonPanel.add(no);buttonPanel.add(cancel); / Methods to query all of the bean properties. public String getMessageText() return messageText; public String getYesLabel() return yesLabel; public String getNoLabel() return noLabel; public String getCancelLabel() return cancelLabel; / Methods to set all of the bean properties. public void setMessageText(String messageText) this.messageText = messageText;message.setText(messageText);validate(); public void setYesLabel(String newYesLabel) yesLabel = newYesLabel;yes.setLabel(newYesLabel);yes.setVisible(newYesLabel != null) & (newYesLabel.length() 0);validate(); public void setNoLabel(String newNoLabel) noLabel = newNoLabel;no.setLabel(newNoLabel);no.setVisible(newNoLabel != null) & (newNoLabel.length() 0);validate(); public void setCancelLabel(String newCancelLabel) cancelLabel = newCancelLabel;cancel.setLabel(newCancelLabel);cancel.setVisible(newCancelLabel != null) & (newCancelLabel.length() 0);validate(); public void setFont(Font f) super.setFont(f); / Invoke the superclass methodmessage.setFont(f); yes.setFont(f);no.setFont(f);cancel.setFont(f);validate(); Bean的测试容器程序代码import java.awt.*;import java.awt.event.*;import java.beans.*;import java.awt.event.WindowListener;import java.awt.event.WindowEvent;public class BeanTestFrame extends Frame implements WindowListenerYesNoPanel panelBean; public BeanTestFrame() super(Java Bean 的测试容器程序); panelBean= new YesNoPanel(Do you really want to quit?); panelBean.setFont(new Font(Dialog,Font.BOLD,20); panelBean.setBackground(Color.red); this.add(panelBean,BorderLayout.CENTER); this.setSize(400,400); this.addWindowListener(this); this.setVisible(true); public static void main(String args) BeanTestFrame frame=new BeanTestFrame(); public void windowOpened(WindowEvent parm1) / TODO: Add your code herepublic void windowClosing(WindowEvent parm1) this.dispose();System.exit(0);public void windowClosed(WindowEvent parm1) / TODO: Add your code herepublic void windowIconified(WindowEvent parm1) / TODO: Add your code herepublic void windowDeiconified(WindowEvent parm1) / TODO: Add your code herepublic void windowActivated(WindowEvent parm1) / TODO: Add your code herepublic void windowDeactivated(WindowEvent parm1) / TODO: Add your code here在应用程序中进行测试在BeanBox中进行测试（2）第二步：为Bean增加BeanInfo类（为Bean提供显式的信息如Bean在应用程序构造器中的属性、图标、事件的名称等）import java.beans.*;import java.awt.*;/* * This BeanInfo class provides additional information about the YesNoPanel * bean in addition to what can be obtained through introspection alone. */public class YesNoPanelBeanInfo extends SimpleBeanInfo public Image getIcon(int iconKind)if(iconKind=BeanInfo.ICON_COLOR_16x16)Image img=this.loadImage(BeanIconColor16.gif);return img;if(iconKind=BeanInfo.ICON_COLOR_32x32)Image img=this.loadImage(BeanIconColor32.gif);return img;return null;/*以下代码位JavaeBean提供在应用程序的构造工具中的显示名称字串*/public BeanDescriptor getBeanDescriptor()BeanDescriptor bd=new BeanDescriptor(YesNoPanel.class); /采用缺省的定制文件创建Bean的描述信息bd.setDisplayName(YesNoPanelBean);/在应用程序的构造工具中的显示名称字串return bd;/*以下代码显式地声明属性*/public PropertyDescriptor getPropertyDescriptors()tryPropertyDescriptor foreground=new PropertyDescriptor(foreground,YesNoPanel.class), background=new PropertyDescriptor(background,YesNoPanel.class), font=new PropertyDescriptor(font,YesNoPanel.class), name=new PropertyDescriptor(name,YesNoPanel.class);/*以上为继承来的属性*/ /*以下为程序中所新增加的属性*/ PropertyDescriptor messageText=new PropertyDescriptor(messageText,YesNoPanel.class), yesLabel=new PropertyDescriptor(yesLabel,YesNoPanel.class), noLabel=new PropertyDescriptor(noLabel,YesNoPanel.class), cancelLabel=new PropertyDescriptor(cancelLabel,YesNoPanel.class); /*可以根据应用的需要，将某些属性在应用程序的构造工具中隐藏起来*/ PropertyDescriptor pd=foreground, background,font,name,messageText,yesLabel,noLabel,cancelLabel;return pd;catch(IntrospectionException e)throw new Error(e.toString();public int getDefaultPropertyIndex()return 4;/将messageText作为缺省的属性（3）第三步：为Bean增加事件处理的功能，使其可响应用户的鼠标点击事件、焦点事件、鼠标进入退出和按下释放等事件Bean的程序代码import java.awt.*;import java.awt.event.*;import java.util.*;import java.awt.event.*;/由于在YesNoPanel Bean中覆盖有yes, no, cancel三个Button，message Label以及buttonPanel 面板。因此，应该将这些组件的MouseListener, FocusListener, ActionListener事件转发给YesNoPanel Bean。public class YesNoPanel extends Panel implements MouseListener, FocusListener, ActionListener / bean的属性 protected String messageText; / The message to display protected String yesLabel; / Text for the yes, no, & cancel buttons protected String noLabel; protected String cancelLabel; / Beans的内部组件 protected Button yes, no, cancel; protected Label message; private transient ActionListener actionListener=null;private transient MouseListener mouseListener=null;private transient FocusListener focusListener=null; /* The no-argument bean constructor, with default property values */ public YesNoPanel() this(Your Message Here); public YesNoPanel(String messageText) this(messageText, Yes, No, Cancel); public YesNoPanel(String messageText, String yesLabel, String noLabel, String cancelLabel) super();/通过调用基类的构造函数，以获得Panel的一般特性 this.messageText=messageText; / The message to display this.yesLabel=yesLabel; / Text for the yes, no, & cancel buttons this.noLabel=noLabel; this.cancelLabel=cancelLabel;this.enableEvents(AWTEvent.FOCUS_EVENT_MASK|/必须设置此方法，否则Bean不能接受事件 AWTEvent.MOUSE_EVENT_MASK|AWTEvent.MOUSE_MOTION_EVENT_MASK|AWTEvent.ACTION_EVENT_MASK);this.setLayout(new BorderLayout(15, 15);/ Put the message label in the middle of the window.message = new Label(messageText);message.addMouseListener(this);message.addFocusListener(this);add(message, BorderLayout.CENTER);/ Create a panel for the Panel buttons and put it at the bottom/ of the Beans Panel. Specify a FlowLayout layout manager for it.Panel buttonPanel = new Panel();buttonPanel.addMouseListener(this);buttonPanel.addFocusListener(this);buttonPanel.setLayout(new FlowLayout(FlowLayout.CENTER, 25, 15);this.add(buttonPanel, BorderLayout.SOUTH);/ Create each specified button, specifying the action listener/ and action command for each, and adding them to the buttonboxyes = new Button(); / Create buttonsyes.addMouseListener(this);yes.addActionListener(this);yes.addFocusListener(this);no = new Button();no.addMouseListener(this);no.addActionListener(this);no.addFocusListener(this);cancel = new Button();cancel.addMouseListener(this);cancel.addFocusListener(this);cancel.addActionListener(this);this.setYesLabel(yesLabel);this.setNoLabel(noLabel);this.setCancelLabel(cancelLabel);/ Add the buttons to the button boxbuttonPanel.add(yes);buttonPanel.add(no);buttonPanel.add(cancel); / Methods to query all of the bean properties. public String getMessageText() return messageText; public String getYesLabel() return yesLabel; public String getNoLabel() return noLabel; public String getCancelLabel() return cancelLabel; / Methods to set all of the bean properties. public void setMessageText(String messageText) this.messageText = messageText;message.setText(messageText);validate(); public void setYesLabel(String newYesLabel) yesLabel = newYesLabel;yes.setLabel(newYesLabel);yes.setVisible(newYesLabel != null) & (newYesLabel.length() 0);validate(); public void setNoLabel(String newNoLabel) noLabel = newNoLabel;no.setLabel(newNoLabel);no.setVisible(newNoLabel != null) & (newNoLabel.length() 0);validate(); public void setCancelLabel(String newCancelLabel) cancelLabel = newCancelLabel;cancel.setLabel(newCancelLabel);cancel.setVisible(newCancelLabel != null) & (newCancelLabel.length() 0);validate(); public void setFont(Font f) super.setFont(f); / Invoke the superclass methodmessage.setFont(f); yes.setFont(f);no.setFont(f);cancel.setFont(f);validate(); /实现维护鼠标点击事件的监听器列表的方法（添加和删除）public synchronized void addActionListener(ActionListener listener)actionListener=AWTEventMulticaster.add(actionListener,listener); public synchronized void removeActionListener(ActionListener listener)actionListener=AWTEventMulticaster.remove(actionListener,listener); public synchronized void addMouseListener(MouseListener listener)mouseListener=AWTEventMulticaster.add(mouseListener,listener); public synchronized void removeMouseListener(MouseListener listener)mouseListener=AWTEventMulticaster.remove(mouseListener,listener); public synchronized void addFocusListener(FocusListener listener)focusListener=AWTEventMulticaster.add(focusListener,listener); public synchronized void removeFocusListener(FocusListener listener)focusListener=AWTEventMulticaster.remove(focusListener,listener); /向所有注册ActionListener的组件分发ActionEvent事件protected void processActionEvent(ActionEvent e)if(actionListener !=null)actionListener.actionPerformed(e);protected void processFocusEvent(FocusEvent e)switch(e.getID()case FocusEvent.FOCUS_GAINED:repaint();if(focusListener !=null)focusListener.focusGained(e);break;case FocusEvent.FOCUS_LOST:repaint();if(focusListener !=null)focusListener.focusLost(e);break;cessFocusEvent(e);protected void processMouseEvent(MouseEvent e)switch(e.getID()case MouseEvent.MOUSE_PRESSED:repaint();if(mouseListener !=null)mouseListener.mousePressed(e);break;case MouseEvent.MOUSE_RELEASED:if(mouseListener !=null)mouseListener.mouseReleased(e);break;case MouseEvent.MOUSE_CLICKED:if(mouseListener !=null)mouseListener.mouseClicked(e);break;case MouseEvent.MOUSE_ENTERED:if(mouseListener !=null)mouseListener.mouseEntered(e);break;case MouseEvent.MOUSE_EXITED:if(mouseListener !=null)mouseListener.mouseExited(e);break;cessMouseEvent(e);/由于在YesNoPanel Bean中覆盖有yes, no, cancel三个Button，message Label以及buttonPanel 面板。因此，应该将这些组件的MouseListener事件转发给YesNoPanel Bean。public void mouseClicked(MouseEvent parm1) processMouseEvent(parm1);public void mousePressed(MouseEvent parm1) processMouseEvent(parm1);public void mouseReleased(MouseEvent parm1) processMouseEvent(parm1);public void mouseEntered(MouseEvent parm1) processMouseEvent(parm1);public void mouseExited(MouseEvent parm1) processMouseEvent(parm1);/由于在YesNoPanel Bean中覆盖有yes, no, cancel三个Button，message Label以及buttonPanel 面板。因此，应该将这些组件的FocusListener事件转发给YesNoPanel Bean。public void focusGained(FocusEvent parm1) processFocusEvent(parm1);public void focusLost(FocusEvent parm1) processFocusEvent(parm1);/由于在YesNoPanel Bean中覆盖有yes, no, cancel三个Button，message Label以及buttonPanel 面板。因此，应该将这些组件的ActionListener事件转发给YesNoPanel Bean。public void actionPerformed(ActionEvent parm1) processActionEvent(parm1);Bean的测试容器程序代码import java.awt.*;import java.awt.event.*;import java.beans.*;import java.awt.event.*public class BeanTestFrame extends Frame implements WindowListener, ActionListener, FocusListener, MouseListenerYesNoPanel panelBean; public BeanTestFrame() super(Java Bean 的测试容器程序); panelBean= new YesNoPanel(Do you really want to quit?); panelBean.setFont(new Font(Dialog,Font.BOLD,20); panelBean.setBackground(Color.red); panelBean.addActionListener(this); panelBean.addMouseListener(this); panelBean.addFocusListener(this); this.add(panelBean,BorderLayout.CENTER); this.setSize(400,400); this.addWindowListener(this); this.setVisible(true); public static void main(String args) BeanTestFrame frame=new BeanTestFrame(); public void windowOpened(WindowEvent parm1) / TODO: Add your code herepublic void windowClosing(WindowEvent parm1) this.dispose();System.exit(0);public void windowClosed(WindowEvent parm1) / TODO: Add your code herepublic void windowIconified(WindowEvent parm1) / TODO: Add your code herepublic void windowDeiconified(WindowEvent parm1) / TODO: Add your code herepublic void windowActivated(WindowEvent parm1) / TODO: Add your code herepublic void windowDeactivated(WindowEvent parm1) / TODO: Add your code herepublic void actionPerformed(ActionEvent parm1) if(parm1.getSource()=panelBean.yes)this.setTitle(您的鼠标点击了PaneBean并且是Yes按钮！);else if(parm1.getSource()=panelBean.no)this.setTitle(您的鼠标点击了PaneBean并且是No按钮！);else if(parm1.getSource()=panelBean.cancel)this.setTitle(您的鼠标点击了PaneBean并且是Cancel按钮！);public void focusGained(FocusEvent parm1) System.out.print(PaneBean获得输入焦点！);public void focusLost(FocusEvent parm1) System.out.print(PaneBean失去输入焦点！);public void mouseClicked(MouseEvent parm1) / TODO: Add your code herepublic void mousePressed(MouseEvent parm1) / TODO: Add your code herepublic void mouseReleased(MouseEvent parm1) / TODO: Add your code herepublic void mouseEntered(MouseEvent parm1) this.setTitle(您的鼠标进入PaneBean所在的区域！);public void mouseExited(MouseEvent parm1) this.setTitle(您的鼠标离开PaneBean所在的区域！);在应用程序中进行测试YesNoPanelBeanInfo程序代码import java.beans.*;import java.awt.*;/* * This BeanInfo class provides additional information about the YesNoPanel * bean in addition to what can be obtained through introspection alone. */public class YesNoPanelBeanInfo extends SimpleBeanInfo public Image getIcon(int iconKind)if(iconKind=BeanInfo.ICON_COLOR_16x16)Image img=this.loadImage(BeanIconColor16.gif);return img;if(iconKind=BeanInfo.ICON_COLOR_32x32)Image img=this.loadImage(BeanIconColor32.gif);return img;retu