我有一个类:超级构造函数不能正常工作如何,我认为它应该
public abstract class LogicGate extends JPanel implements PropertyChangeListener {
private Image image;
private URL url;
private OutputTerminal output;
private Terminal input0;
private Terminal input1;
public LogicGate(String fileName) {
this.url = getClass().getResource(fileName);
this.image = new javax.swing.ImageIcon(url).getImage();
this.setSize(image.getWidth(null), image.getHeight(null));
this.output = new OutputTerminal();
}
}
和子类:
public class ANDGate extends LogicGate {
private OutputTerminal output;
private Terminal input0;
private Terminal input1;
public ANDGate() {
super("images/AND.gif");
System.out.println(this.output);
}
}
然而,当我调用一个新的ANDGate
对象,output
为空,当它应该已经分配了(按照超级构造函数)。
现在很清楚,我在理解子类的构造函数时做了一个假设;我究竟做错了什么?
那么这一切固定。感谢:D –