11.19

软件设计                  石家庄铁道大学信息学院

 

实验18：迭代器模式

本次实验属于模仿型实验，通过本次实验学生将掌握以下内容： 

1、理解迭代器模式的动机，掌握该模式的结构；

2、能够利用迭代器模式解决实际问题。

 

[实验任务一]：JAVA和C++常见数据结构迭代器的使用

信1305班共44名同学，每名同学都有姓名，学号和年龄等属性，分别使用JAVA内置迭代器和C++中标准模板库（STL）实现对同学信息的遍历，要求按照学号从小到大和从大到小两种次序输出学生信息。

实验要求：

1. 搜集并掌握JAVA和C++中常见的数据结构和迭代器的使用方法，例如，vector, list, map和set等；

①、ArrayList1.java

package org.example.shiyanshiba;

import java.util.ArrayList;
import java.util.Iterator;

public class ArrayList1 {
    public static void main(String[] args) {
        ArrayList<Integer> arrayList = new ArrayList<>();
        arrayList.add(1);
        arrayList.add(2);
        arrayList.add(3);
        System.out.println(arrayList);
        Iterator<Integer> iterator = arrayList.iterator();
        while (iterator.hasNext()) {
            System.out.println(iterator.next());
        }
    }
}

 

 

②、LinkedList.java

package org.example.shiyanshiba;

import java.util.Iterator;
import java.util.LinkedList;

public class LinkedList1 {
    public static void main(String[] args) {
        LinkedList<String> linkedList = new LinkedList<>();
        linkedList.add("a");
        linkedList.add("b");
        linkedList.add("c");
        System.out.println(linkedList);
        Iterator<String> iterator = linkedList.iterator();
        while (iterator.hasNext()) {
            String element = iterator.next();
            System.out.println(element);
        }
    }
}

 

 

 

③、HashMap.java

package org.example.shiyanshiba;

import java.util.HashMap;
import java.util.Map;

public class HashMap1 {
    public static void main(String[] args) {
        HashMap<String,Integer> hashMap=new HashMap<>();
        hashMap.put("a",1);
        hashMap.put("b",2);
        hashMap.put("c",3);
        System.out.println(hashMap);
        for(Map.Entry<String,Integer> entry:hashMap.entrySet()){
            System.out.println(entry.getKey()+": "+entry.getValue());
        }
    }
}

 

 

④、HashSet.java

package org.example.shiyanshiba;

import java.util.HashSet;
import java.util.Iterator;

public class HashSet1 {
    public static void main(String[] args) {
        HashSet<String> hashSet=new HashSet<>();
        hashSet.add("a");
        hashSet.add("b");
        hashSet.add("c");
        System.out.println(hashSet);
        Iterator<String> iterator=hashSet.iterator();
        while(iterator.hasNext()){
            String element=iterator.next();
            System.out.println(element);
        }
    }
}

 

 

2. 提交源代码；

①、Student.java

package org.example.shiyanshiba;

public class Student implements Comparable<Student> {
    private int studentid;
    private String name;
    private int age;

    public Student(int studentid, String name, int age) {
        this.studentid = studentid;
        this.name = name;
        this.age = age;
    }

    @Override
    public int compareTo(Student o) {
        if (this.studentid < o.studentid) {
            return -1;
        } else if (this.studentid > o.studentid) {
            return 1;
        } else {
            return 0;
        }
    }
    @Override
    public String toString() {
        return "姓名："+this.name+"，学号："+this.studentid+"，年龄："+this.age;
    }
}

 

②、Student2.java

package org.example.shiyanshiba;

public class Student2 implements Comparable<Student2> {
    private int studentid;
    private String name;
    private int age;

    public Student2(int studentid, String name, int age) {
        super();
        this.studentid = studentid;
        this.name = name;
        this.age = age;
    }

    @Override
    public int compareTo(Student2 o) {
        if (this.studentid < o.studentid) {
            return -1;
        } else if (this.studentid > o.studentid) {
            return 1;
        } else {
            return 0;
        }
    }
    @Override
    public String toString() {
        return "姓名："+this.name+"，学号："+this.studentid+"，年龄："+this.age;
    }
}

 

③、Client.java

package org.example.shiyanshiba;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

public class Client {
    public static void main(String[] args) {
        Student s1=new Student(20223730,"陈志峰",21);
        Student s2=new Student(20223731,"叶振钧",21);
        Student s3=new Student(20223732,"王晓菲",21);
        Student s4=new Student(20223733,"梁家显",21);
        Student s5=new Student(20223734,"李文举",21);
        Student s6=new Student(20223735,"陈庆振",20);
        Student2 s7=new Student2(20223730,"陈志峰",21);
        Student2 s8=new Student2(20223731,"叶振钧",21);
        Student2 s9=new Student2(20223732,"王晓菲",21);
        Student2 s10=new Student2(20223733,"梁家显",21);
        Student2 s11=new Student2(20223734,"李文举",21);
        Student2 s12=new Student2(20223735,"陈庆振",20);
        List<Student> list=new ArrayList<>();
        list.add(s1);
        list.add(s2);
        list.add(s3);
        list.add(s4);
        list.add(s5);
        list.add(s6);
        Collections.sort(list);
        System.out.println("学号按从大到小输出：");
        for(Student student:list){
            System.out.println(student.toString());
        }
        System.out.println("``````````````````````");
        List<Student2> list2=new ArrayList<>();
        list2.add(s7);
        list2.add(s8);
        list2.add(s9);
        list2.add(s10);
        list2.add(s11);
        list2.add(s12);
        Collections.sort(list2);
        System.out.println("年龄从大到小输出：");
        for(Student2 student:list2){
            System.out.println(student.toString());
        }
        System.out.println("``````````````````````");
    }
}

 

3. 注意编程规范。