书中有很多的程序清单,其中有的没有main函数。我是Java初学者,想看看程序的运行效果,但是对于没有main函数的程序不知道怎么运行。请问各位大牛当时是怎么解决的?
程序清单8-3 action/ActionFrame.java
"package action;
import java.awt.Color;
import java.awt.event.ActionEvent;
import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.ActionMap;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.InputMap;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.KeyStroke;
public class ActionFrame extends JFrame{
private JPanel buttonPanel;
private static final int DEFAULT_WIDTH = 300;
private static final int DEFAULT_HEIGHT = 200;
public ActionFrame()
{
setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
buttonPanel = new JPanel();
//define actions
Action yellowAction = new ColorAction("Yellow", new ImageIcon("yellow-ball.gif"),Color.YELLOW);
Action blueAction = new ColorAction("Blue", new ImageIcon("blue-ball.gif"),Color.BLUE);
Action redAction = new ColorAction("Red", new ImageIcon("red-ball.gif"),Color.RED);
//add buttons for these actions
buttonPanel.add(new JButton(yellowAction));
buttonPanel.add(new JButton(blueAction));
buttonPanel.add(new JButton(redAction));
//add panel to frame
add(buttonPanel);
//associate the Y, B, and R keys with names
InputMap imap = buttonPanel.getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT);
imap.put(KeyStroke.getKeyStroke("ctrl Y"), "panel.yellow");
imap.put(KeyStroke.getKeyStroke("ctrl B"), "panel.blue");
imap.put(KeyStroke.getKeyStroke("ctrl R"), "panel.red");
//associate the names with actions
ActionMap amap = buttonPanel.getActionMap();
amap.put("panel.yellow", yellowAction);
amap.put("panel.blue", blueAction);
amap.put("panel.red", redAction);
}
public class ColorAction extends AbstractAction
{
/**
* Constructs a color action.
* @param name the name to show on the button
* @param icon the icon to display on the button
* @param c the background color
*/
public ColorAction(String name, Icon icon, Color c)
{
putValue(Action.NAME, name);
putValue(Action.SMALL_ICON, icon);
putValue(Action.SHORT_DESCRIPTION, "Set panel color to " + name.toLowerCase());
putValue("color", c);
}
public void actionPerformed(ActionEvent event)
{
Color c = (Color) getValue("color");
buttonPanel.setBackground(c);
}
}
}
"
------解决思路----------------------
自己加main的方法:
public static void main(String[] args)
{
ActionFrame frame = new ActionFrame();
frame.setVisible(true);
}
------解决思路----------------------
main函数?实际应用中你几乎永远看不到它,它只出现在课本里
正解。
我也看过java核心技术,这本书还不错。主要是理解代码的逻辑和做了什么事情。至于想看结果的话,方法有很多啊,自己加一个main可以,使用junit的@Test来进行测试也可以啊。