4.11小节中，我的ForEach不知道为什么没有运行，麻烦帮看一下，感激不尽啊
package com.imooc.collection;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Scanner;
public class SetTest{
public List coursesToSelect;
public SetTest(){
coursesToSelect =new ArrayList();
}
public class ListTest{
/*
用于存放备选课程的List
*/
public List coursesToSelect;
public ListTest(){
this.coursesToSelect=new ArrayList();
}
/*
用于往coursesToSelect中添加备选课程
*/
public void testAdd(){
//创建一个课程对象，并通过调用add方法，添加到备选课程List中
Course cr1=new Course("1","数据结构");
coursesToSelect.add(cr1);
Course temp=(Course)coursesToSelect.get(0);
//System.out.println("添加了课程:"+temp.id+":"+temp.name);
Course cr2=new Course("2","c语言");
coursesToSelect.add(0,cr2);
Course temp2=(Course)coursesToSelect.get(0);
//System.out.println("添加了课程:"+temp2.id+":"+temp2.name);
//coursesToSelect.add(cr1);
//Course temp0=(Course)coursesToSelect.get(2);
//System.out.println("添加了课程:"+temp0.id+":"+temp0.name);
Course[] course={new Course("3","离散数学"),new Course("4","汇编语文"
)};
coursesToSelect.addAll(Arrays.asList(course));
Course temp3=(Course)coursesToSelect.get(3);
Course temp4=(Course)coursesToSelect.get(4);
//System.out.println("添加了两门课程:"+temp3.id+":"+temp3.name+";"+temp4.id+":"+temp4.name);
Course[] course2={new Course("5","高等数学"),new Course("6","大学英语")};
coursesToSelect.addAll(2,Arrays.asList(course));
Course temp5=(Course)coursesToSelect.get(2);
Course temp6=(Course)coursesToSelect.get(3);
//System.out.println("添加了两门课程:"+temp5.id+":"+temp5.name+";"+temp6.id+":"+temp6.name);
}
}
/*
通过for each方法访问集合元素
*/
public void testForEach(){
System.out.println("有如下课程待选(通过for each访问)：");
for(Object obj:coursesToSelect){
Course cr=(Course)obj;
System.out.println("课程:"+cr.id+":"+cr.name);
}
}
public static void main(String[] args){
SetTest st=new SetTest();
st.testAdd();
st.testForEach();
//创建一个学生对象
Student student=new Student("1","小明");
System.out.println("欢迎学生："+student.name+"选课！");
//创建一个Scanner对象，用来接收从键盘输入的课程ID
Scanner console=new Scanner(System.in);
for(int i=0;i |
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