Java基础学习Day09

ゝ一世哀愁。 2021-11-02 12:02 323阅读 0赞

#### 知识点 ####

1.  集合

##### 集合 #####

集合概述：  
存储引用类型数据的容器  
Collection集合：存取数据时是单个存取  
常用方法：add isEmpty size contains remove removeAll toArray iterator  
Iterator是Collection的父类  
常用方法：hasNext() next()  
List集合：有序可重复，主要增加了索引值的操作  
常用方法：get(int index)  
Map集合：是按<健, 值>对的形式存取数据

#### 课后练习 ####

package com.day09;
    
    public class User {
        
    	private int id;
    	private String name;
    	private String password;
    	private int age;
    	private String sex;
    	
    	public int getId() {
        
    		return id;
    	}
    	
    	public void setId(int id) {
        
    		this.id = id;
    	}
    	
    	public String getName() {
        
    		return name;
    	}
    	
    	public void setName(String name) {
        
    		this.name = name;
    	}
    	
    	public String getPassword() {
        
    		return password;
    	}
    	
    	public void setPassword(String password) {
        
    		this.password = password;
    	}
    	
    	public int getAge() {
        
    		return age;
    	}
    	
    	public void setAge(int age) {
        
    		this.age = age;
    	}
    	
    	public String getSex() {
        
    		return sex;
    	}
    	
    	public void setSex(String sex) {
        
    		this.sex = sex;
    	}
    	
    	public void print() {
        
    		System.out.printf("ID:%d\tName:%s\tPassword:%s\tAge:%d\tSex:%s\n",
    				id, name, password, age, sex);
    	}
    }

package com.day09;
    
    public interface IFuncation {
        
    	public abstract void add();
    	public abstract void delete();
    	public abstract void revise();
    	public abstract void query();
    }

package com.day09;
    
    import java.util.ArrayList;
    import java.util.List;
    import java.util.Scanner;
    
    import com.day04.Array;
    
    public class FuncationImpl implements IFuncation{
        
    	private Scanner sca = new Scanner(System.in);
    	public static List<User> array = new ArrayList<User>();
    
    	@Override
    	public void add() {
        	
    		User temp = new User();
    		System.out.print("请输入添加的用户名：");
    		temp.setName(sca.next());
    		System.out.print("请设置该用户的密码：");
    		temp.setPassword(sca.next());
    		System.out.print("请设置该用户的年龄：");
    		temp.setAge(sca.nextInt());
    		System.out.print("请设置该用户的性别：");
    		temp.setSex(sca.next());
    		temp.setId(array.size());
    		array.add(temp);
    		System.out.println("添加成功0-0");
    		return ;
    	}
    
    	@Override
    	public void delete() {
        
    		if(array.size() == 0) {
        
    			System.out.println("用户不可再删，删除失败0-0");
    			return ;
    		}
    		System.out.print("请输入要删除的编号：");
    		int id = sca.nextInt();
    		for(int i = 0; i < array.size(); i++) {
        
    			if(id == array.get(i).getId()) {
        
    					array.remove(i);
    				System.out.println("删除成功0-0");
    				return ;
    			}
    		}
    		System.out.println("查找不到所输入的编号0-0");
    		return ;
    	}
    
    	@Override
    	public void revise() {
        
    		System.out.print("请输入您索要修改的编号：");
    		int id = sca.nextInt();
    		for(int i = 0; i < array.size(); i++) {
        
    			if(id == array.get(i).getId()) {
        
    				System.out.println("请修改以下数据：");
    				System.out.print("Name:");
    				array.get(i).setName(sca.next());
    				System.out.print("Age:");
    				array.get(i).setAge(sca.nextInt());
    				System.out.print("Sex:");
    				array.get(i).setSex(sca.next());
    				System.out.println("修改成功0-0");
    				return ;
    			}
    		}
    		System.out.println("查找不到所输入的编号0-0");
    		return ;
    	}
    
    	@Override
    	public void query() {
        
    		for(int i = 0; i < array.size(); i++) {
        
    			array.get(i).print();			
    		}
    	}
    	
    	
    }

package com.day09;
    
    import java.util.Scanner;
    
    public class LemonSystem {
        
    	private static int n;
    	private static Scanner sca = new Scanner(System.in);
    	public static void main(String[] args) {
        
    		FuncationImpl funcationImpl = new FuncationImpl();
    		while(true) {
        
    			System.out.println("欢迎来到小柠檬系统0-0");
    			System.out.println("1. 登陆");
    			System.out.println("2. 注册");
    			System.out.println("0. 退出");
    			n = sca.nextInt();
    			if(n == 1) {
        
    				login(funcationImpl);
    			}
    			if(n == 2) {
        
    				register(funcationImpl);
    			}
    			if(n == 0) {
        
    				return ;
    			}			
    		}
    	}
    	
    	public static void register(FuncationImpl funcationImpl) {
        
    		User temp = new User();
    		System.out.print("请输入用户名：");
    		temp.setName(sca.next());
    		System.out.print("请设置该用户的密码：");
    		temp.setPassword(sca.next());
    		System.out.print("请设置该用户的年龄：");
    		temp.setAge(sca.nextInt());
    		System.out.print("请设置该用户的性别：");
    		temp.setSex(sca.next());
    		temp.setId(0);
    		FuncationImpl.array.add(temp);
    		System.out.println("注册成功0-0");
    		return ;
    	}
    	
    	public static void login(FuncationImpl funcationImpl) {
        
    		System.out.print("请输入用户名：");
    		String name = sca.next();
    		System.out.print("请输入密码：");
    		String password = sca.next();
    		if(funcationImpl.array.get(0).getName().equals(name) && 
    				funcationImpl.array.get(0).getPassword().equals(password)) {
        
    			System.out.println("登陆成功0-0");
    			while(true) {
        
    				System.out.println("欢迎进入小柠檬内部系统0-0");
    				System.out.println("1. 添加");
    				System.out.println("2. 删除");
    				System.out.println("3. 修改");
    				System.out.println("4. 查询");
    				System.out.println("0. 退出");
    				n = sca.nextInt();
    				if(n == 1) {
        
    					funcationImpl.add();
    				}
    				if(n == 2) {
        
    					funcationImpl.delete();
    				}
    				if(n == 3) {
        
    					funcationImpl.revise();
    				}
    				if(n == 4) {
        
    					funcationImpl.query();
    				}
    				if(n == 0) {
        
    					break ;
    				}
    			}
    			return ;
    		}
    		System.out.println("登陆失败0-0");
    		return ;
    	}
    }