实在不明白,请来看看~~~
以下是两段简单的代码,但有几个地方不是很懂,请帮忙解释下,谢谢~~~~对了,所有帮忙解答的朋友,请说的详细些,我比较菜!!!
第一段:
import java.util.Random;
public class MagicHat{
static int maxRabbits = 5;
static Random select = new Random();
public MagicHat(String hatName){
this.hatName = hatName;
rabbits = new Rabbit[1 + select.nextInt(maxRabbits)];
for(int i = 0; i <rabbits.length; i++){
rabbits[i] = new Rabbit();
}
}
public String toString(){ //问题标签
String hatString = "\n" + hatName + " contains:\n";
for(Rabbit rabbit : rabbits){ //问题标签
hatString += " " + rabbit;
}
return hatString;
}
private String hatName;
private Rabbit rabbits[];
static class Rabbit{
static private String[] rabbitNames = {"Floppsy", "Moppsy", "Gnasher", "Thumper"};
static private int[] rabbitNamesCount = new int[rabbitNames.length];
private String name;
public Rabbit(){
int index = select.nextInt(rabbitNames.length);
name = rabbitNames[index] + (++rabbitNamesCount[index]); //问题标签
}
public String toString(){
return name;
}
}
}
第二段:
public class TryNestedClass{
static public void main(String[] args){
System.out.println(new MagicHat("Gray Topper"));
System.out.println(new MagicHat("Black Topper"));
System.out.println(new MagicHat("Baseball Cap"));
}
}
问题1:
(++rabbitNamesCount[index])int类型会先将自己初试化为0,然后再将=号后面的值赋予变量,是这样子伐??
那么对于数组呢?变量拥有的仅仅只是引用而已,它又怎么把它变成数字的呢??
问题2:
for(Rabbit rabbit : rabbits){//Rabbit是嵌套的类。rabbit这里是Rabbit的类变量。rabbits是个只有元素数,没有实际数据的数组
hatString += " " + rabbit; //这个不是应该根据rabbits的数组元素来,决定循环的次数的吗?但是结果是每次调用,只循环了一次。但是,rabbits数组里的元素只止一个!!
}
问题3:
这段代码中,最后通过toString来显示类对象,它在哪里被调用了?toString()是作为运算符操作数时自动调用的吧,可是第二段代码中,哪来的运算符?
问题4:
整段代码要显示嵌套类的内容,但是我却不知道在哪里调用了嵌套类Rabbit,难道是上面的for循环??为什么呢?