数组总结Java实验 java数组的实验报告

1 .实 验 名 称 类与对象（1）

2 .实 验 目 的 （1）学会类的实现、类的使用和用 UML 类图描述类之间的关系，能够对实际的案例进行分 析和建模，并画出类图。 （2）能够根据类图进行编码实现。 （3）理解构造方法的概念和重载的概念，能在程序设计中灵活应用。 （4）巩固数组在面向对象程序设计中的运用；

3 .训 练 知 识 点 集 群 （1）类的语法（类的成员变量和成员方法、构造方法、成员变量的 getter、setter 方法等） （2）类图（单个类的类图和类之间的关系） （3）使用数组构造线性表

4 .实 验 内 容 （1）计算某长方体或正方体盒子的体积 （2）课程融合之线性表 ➢ 定义一个类 MyArrayList，用数组模拟实现数据结构中线性表的基本功能，该类中最少包 含的属性有：data（String[]）、size（int）、CAPACITY（int）; ➢ 该类中方法最少包括线性表的初始化、插入 、查找、遍历线性表、删除、返回线性表 长度、线性表判空、清空线性表、替换、获取元素、判断线性表中是否包含某个元素、 反向查找、末尾插入元素； ➢ 定义一个主类，在主方法中创建线性表类对象并调用上述方法、完成功能演示。

一 计算机类Calculator:

package Calculator;
import java.util.Scanner;
class Calculator {
    private float num1;
    private float num2;
    private String op;
    public Calculator(float num1,float num2,String op){
        this.num1=num1;
        this.num2=num2;
        this.op=op;
    }
    public void cal(String op){

        if(op.equals("+")){
            float i=num1+num2;
            System.out.println(i);
        }
        else if(op.equals("-")){
            float i=num1-num2;
            System.out.println(i);
        }
        else if(op.equals("*")){
            float i=num1*num2;
            System.out.println(i);
        }
        else if(op.equals("/")){
            float i=num1/num2;
            System.out.println(i);
        }
    }
}
    public  class TestCalculator{
        public static void main(String[] args){
            Scanner sc=new Scanner(System.in);
            System.out.println("请输入操作符");
            String op=sc.next();
            System.out.println("请输入num1");
            float num1=sc.nextFloat();
            System.out.println("请输入num2");
            float num2=sc.nextFloat();
            Calculator c=new Calculator(num1,num2,op);
            c.cal(op);
        }
    }

二 电商购物平台:

import java.util.Scanner;
class category {
    private int id;//编号
    private String fristlevel;//一级目录
    private String secondlevel;//二级目录
    public category(int id,String fristlevel,String secondlevel){
        this.id=id;
        this.fristlevel = fristlevel;
        this.secondlevel = secondlevel;
    }
    public String toString(){
        //小说>名著
        return fristlevel+">"+secondlevel;
    }
}
class book {
    private int bid;//编号
    private String name;//书名
    private String author;//作者
    private float price;//价格
    private int num;//库存
    private category category;//书籍类目
    public book(int bid, String name, String auther, float price, int num, category category){
        this.bid=bid;
        this.name=name;
        this.author=auther;
        this.price=price;
        this.num=num;
        this.category=category;
    }

    public String getName() {
        return name;
    }

    public int getBid() {
        return bid;
    }

    public float getPrice() {
        return price;
    }

    public String toString() {
        return "book{" +
                "bid=" + bid +
                ", name='" + name + '\'' +
                ", author='" + author + '\'' +
                ", price=" + price +
                ", num=" + num +
                ", category=" + category +
                '}';
    }
}
class bookDataSet {
    //数组的声明
    public book[] books;//用数组模拟书籍数据库
    //构造方法
    public bookDataSet(){
        books=new book[4];//测试
        category category1=new category(1,"小说","名著");
        category category2=new category(2,"计算机","算法");
        books[0]=new book(1,"数据结构与算法","严蔚敏",54.6f,30,category2 );
        books[1]=new book(2,"算法设计与分析","李华玲",78.6f,20,category2 );
        books[2]=new book(3,"西游记","吴承恩",64.6f,20,category1 );
        books[3]=new book(4,"红楼梦","曹雪芹",84.6f,20,category1 );

    }
    public book[] getBooks(){
        return books;
    }

    public book SearchByName(String name){
        book b=null;
        for (int i=0;i<books.length;i++){
            if(books[i].getName().equals(name)){
                return books[i];
            }
        }
        return b;
    }

    public book ChangeByBid(int bid) {
        book c = null;
        for (int j = 0; j < books.length; j++) {
            if (books[j].getBid() == bid) {
                return books[j];
            }
        }
        return c;
    }
}
public class testshopping {
    public static void main(String[] args){
        bookDataSet bookDataSet = new bookDataSet();
        book[] books = bookDataSet.getBooks();
        for(book b:books){
            System.out.println(b);
        }
        System.out.println("请输入你想查找的书籍名:");
        Scanner sc = new Scanner(System.in);
        String name = sc.next();
        book b = bookDataSet.SearchByName(name);
        if(b!=null){
            System.out.println("这本书的价格是："+bookDataSet.SearchByName(name).getPrice());
        }else System.out.println("查无此书");

        //商品的录入
        System.out.println("请输入你想录入书籍的数量：");
        int num = sc.nextInt();
        for (int j=0;j<num;j++) {
            book[] books1 = new book[books.length + num+1];
            for (int i = 0; i < books.length; i++) {
                //将旧的数组赋值给新数组
                books1[i] = books[i];
            }
            System.out.println("录入的书籍为：" + "5" + "水浒传" + "施耐庵" + 55.5f + 20 + new category(1,"小说","名著"));
            books1[books.length + num-1] =
                    new book(5, "水浒传", "施耐庵", 55.5f, 20, new category(1,"小说","名著"));
            for (book f : books1) {
                System.out.println(f);
            }
        }

        //商品的修改
        System.out.println("请输入想要修改的书籍bid：");
        bookDataSet bookDataSet2 = new bookDataSet();
        book[] books2 = bookDataSet2.getBooks();
        int id1 = sc.nextInt();
        book c = bookDataSet2.ChangeByBid(id1);
        if(c!=null){
            System.out.println("要将其修改为：");
            int bid2 = sc.nextInt();
            books2 = new book[books.length+1];
            books2[bid2] = books[bid2];
            System.out.println("已修改为："+"5" + "水浒传" + "施耐庵" + 55.5f + 20 + new category(1,"小说","名著"));
            books2[b.getBid()] = new book(5 , "水浒传" , "施耐庵" ,55.5f , 20 , new category(1,"小说","名著"));
            for (book f : books2) {
                System.out.println(f);
            }
        }else System.out.println("查无此书");
    }
}