class Meal( Meal()( System.out.println("Meal()"); ) 上 class Bread ( Bread()( System.out.println("Bread()");) ) class Cheese ( Cheese()( System.out.println("Cheese()");) ) class Lettuce( Lettuce() ( System.out.println("Lettuce()"); ) ) class Lunch extends Meal ( Lunch() ( System.out.print1n("Lunch()"); ) ) class PortableLunch extends Lunch ( PortableLunch()( System.out.println("PortableLunch()");I) public class Sandwich extends PortableLunch( private Bread b = new Bread(); private Cheese c = new Cheese(); private Lettuce 1= new Lettuce(); public Sandwich()( System.out.println("Sandwich()"); ) public static void main(String[ ] args) ( new Sandwich( ); 得出运行结果并演示运行过程
时间: 2023-10-29 11:04:26 浏览: 82
代码中存在语法错误,请注意括号的匹配。修正后的代码如下:
```
class Meal {
Meal() {
System.out.println("Meal()");
}
}
class Bread {
Bread() {
System.out.println("Bread()");
}
}
class Cheese {
Cheese() {
System.out.println("Cheese()");
}
}
class Lettuce {
Lettuce() {
System.out.println("Lettuce()");
}
}
class Lunch extends Meal {
Lunch() {
System.out.println("Lunch()");
}
}
class PortableLunch extends Lunch {
PortableLunch() {
System.out.println("PortableLunch()");
}
}
public class Sandwich extends PortableLunch {
private Bread b = new Bread();
private Cheese c = new Cheese();
private Lettuce l = new Lettuce();
public Sandwich() {
System.out.println("Sandwich()");
}
public static void main(String[] args) {
new Sandwich();
}
}
```
运行结果为:
```
Meal()
Lunch()
PortableLunch()
Bread()
Cheese()
Lettuce()
Sandwich()
```
运行过程如下:
1. 程序开始执行,main方法被调用,创建一个Sandwich对象。
2. 创建Sandwich对象时,先调用PortableLunch的构造函数,输出"PortableLunch()"。
3. PortableLunch的构造函数中,调用父类Lunch的构造函数,输出"Lunch()"。
4. Lunch的构造函数中,调用父类Meal的构造函数,输出"Meal()"。
5. Meal的构造函数执行完毕,返回到Lunch的构造函数,继续执行输出"Lunch()"。
6. Lunch的构造函数执行完毕,返回到PortableLunch的构造函数,继续执行输出"PortableLunch()"。
7. PortableLunch的构造函数执行完毕,返回到Sandwich的构造函数,继续执行输出"Sandwich()"。
8. 创建Sandwich对象时,同时创建了一个Bread对象、一个Cheese对象、一个Lettuce对象。
9. Bread、Cheese、Lettuce的构造函数分别被调用,输出"Bread()"、"Cheese()"、"Lettuce()"。
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