哈希表

基本介绍

哈希表实现

package com.company.hash;

import javafx.css.Size;

import javax.sound.midi.Soundbank;

/**
 * @Function :
 * date 2021/5/18 - 16:04
 * How :
 */
public class HashTable {
    public static void main(String[] args) {
        HashTab hashTab = new HashTab(24);
        for (int i = 0; i < 200; i++) {
            hashTab.add(new Employ(i,"employ"+i,"男"));
        }
        hashTab.list();

        Employ employById = hashTab.findEmployById(125);
        System.out.println("===========================================");
        System.out.println(employById);
        System.out.println("===========================================");
    }
}
//hash表
class HashTab{
    private EmployLinkedList[] employLinkedArray;
    int size;
    public HashTab(int size) {
        this.size =size;
        this.employLinkedArray = new EmployLinkedList[this.size];
        for (int i = 0; i < employLinkedArray.length; i++) {
            employLinkedArray[i] = new EmployLinkedList();
        }
    }

    public void add(Employ emp){
        int num = hashFunc(emp.id);
        employLinkedArray[num].add(emp);
    }

    public int hashFunc(int id){
        return id % this.size;
    }

    public void list(){
        for (int i = 0; i < size; i++) {
            System.out.println();
            EmployLinkedList tempEmp = employLinkedArray[i];
            tempEmp.list(i);
            System.out.println();
        }
    }

    public Employ findEmployById(int id){
        int Arrayid = id % size;
        Employ employById = employLinkedArray[Arrayid].findEmployById(id);
        return employById;
    }
}

//雇员
class Employ{
    public int id;
    public String name;
    public String sex;
    public Employ nextNode;

    public Employ() {
    }

    public Employ(int id, String name, String sex) {
        this.id = id;
        this.name = name;
        this.sex = sex;
    }

    @Override
    public String toString() {
        return "Employ{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", sex='" + sex ;
    }
}

//链表
class EmployLinkedList{
    private Employ headNode;

    public EmployLinkedList() {
        this.headNode = null;
    }

    public void add(Employ emp){
        if (headNode == null){
            headNode = emp;
            return;
        }
        Employ tempEmp = headNode;
        while (true){
            if (tempEmp.nextNode == null){
                break;
            }
            tempEmp = tempEmp.nextNode;
        }
        tempEmp.nextNode = emp;
    }

    public void list(int no){
        no++;
        System.out.println("第"+no+"个链表");
        if (headNode == null){
            System.out.println("空！");
            return;
        }
        Employ tempEmp = headNode;
        while (true){
            System.out.printf(tempEmp.toString());
            System.out.println();
            if (tempEmp.nextNode == null){
                break;
            }
            tempEmp = tempEmp.nextNode;
        }
    }

    public Employ findEmployById(int id){
        Employ crrent = headNode;
        while (true){
            if (crrent.id == id){
                return crrent;
            }
            if (crrent.nextNode == null){
                System.out.println("未找到");
                return null;
            }
            crrent = crrent.nextNode;
        }
    }
}

后记

未实现 改 删功能