Java 类和List集合 迭代器遍历练习题

1.  创建班级类(Classes)，具有两个属性：班级人数，班级名称；创建学生类(Student),具有三个属性：学生姓名，学号，所在班级(Classes类型对象)，所有属性都通过构造方法赋值，并具有相应存取器方法。在测试类中，创建存储Student类型的List，并向其添加十个学生的信息，通过迭代器，迭代该List，并将学生所在班级名称打印到控制台。

 import java.util.ArrayList; import java.util.Arrays; import java.util.List; import java.util.ListIterator; //定义一个班级类
class Classes{ private int count; private String name; //构造方法
public Classes(int count, String name) { super(); this.count = count; this.name = name; } //getter/setter方法
public int getCount() { return count; } public void setCount(int count) { this.count = count; } public String getName() { return name; } public void setName(String name) { this.name = name; } } //定义一个学生类
class Student { private String name; private String id; private Classes classes; public Student(String name, String id, Classes classes) { this.name = name; this.id = id; this.classes = classes; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getId() { return id; } public void setId(String id) { this.id = id; } public Classes getClasses() { return classes; } public void setClasses(Classes classes) { this.classes = classes; } } public class Test1_06 { public static void main(String[] args) {
 List list = new ArrayList (); Classes cla = new Classes(10, "java0421");  //生成班级

    for (int i = 0; i < 10; i++) {   //循环10遍
        Student s = new Student(""+i, i+"", cla);  //生成学生
        list.add(s);  //添加学生 
 } //通过迭代器，迭代该list集合
    for(ListIterator it = list.listIterator();it.hasNext();) { Object obj = it.next(); if (obj instanceof Student) { Student s = (Student) obj; System.out.println(s.getClasses().getName()); } } } }