6~7章复习总结

编程入门行业动态更新时间:2024-10-11 13:27:25

6~7章复习总结

第一章开宗明义

讲解面向对象编程的概念
讲解面向对象三大特征
开发"天气预报"项目

第二章面向对象的基础认知

2-1 介绍类与对象

JAVA创建类的语法:

public class Dog {

//类的内容

}

创建类的实例对象:

类名对象名 = new 类名();

2-2 IDEA创建类与对象

public class Dog {  public static void main(String[] args){Dog duoduo - new Dog();Dog lucky - new Dog();}}

2-3 成员变量

public class Dog { //创建类  
String name;int age;//定义整型变量float weight;//定义浮点型变量
public static void main(String[] args){ //主方法Dog duoduo = new Dog(); //转换对象Dog lucky = new Dog();duoduo.name = "多多";duoduo.age = 6;duoduo.weight = 13.5f;Dog lucky = "Lucky";lucky.age = 3;lucky.weight = 10.2f;System.out.println(duoduo.name + "今天" + duoduo.age + "岁了");//输出信息System.out.println(lucky.name + "体重" + duoduo.age + "千克");//输出信息}
}

2-4 方法的作用

public class MethodSample01 {public String isOddNumber(int num) {if(num % 2 --- 0)  {return "偶数";} else {return "奇数";}} public static void main (String[ ] args) {/*  int a = 10;if(a % 2 == 0) {System.out.println(a + "是偶数");} else {System.out.println(a + "是奇数");}int b = 5;if(b % 2 ==0);{System.out.println(b + "是偶数");}else {System.out.println(a + "是奇数");
*//}int a = 10;MethodSample01 macthodSample01 = new MethodSampleo1( );String r1 = methodSample01.isOddNumber(a);System.out.println(a + "是" + r1);int b =5;System.out.println( b +"是" + r2);}}

public class MethodSample01 {public String isOddNumber(int num) {
System.out.println("原始数字为:" + num);if(num % 2 --- 0)  {return "偶数";} else {return "奇数";}} public static void main (String[ ] args) {/*  int a = 10;if(a % 2 == 0) {System.out.println(a + "是偶数");} else {System.out.println(a + "是奇数");}int b = 5;if(b % 2 ==0);{System.out.println(b + "是偶数");}else {System.out.println(a + "是奇数");
*//}int a = 10;MethodSample01 macthodSample01 = new MethodSampleo1( );String r1 = methodSample01.isOddNumber(a);System.out.println(a + "是" + r1);int b =5;System.out.println( b +"是" + r2);}}

第三章面向对象特性及封装

3-1 packge- 包

创建package-包

package com.imooc.object.project.sample2;//import关键字用于导入其他包的类import   com.imooc.object.project.sample1.PackageSample01;public class PackageSample02 {public static void main(Strin [ ] args) {//要使用其他包下的类必须先import导入PackageleSample01 packageSample01 = new  PackageleSample01();}}

3-2访问修饰符

public class PackageSample01 {//public代表其他任何类都能访问的成员变量public String name;//private void sayHello() {System.out.println("Hello world");}//不写访问修饰符代表是默认修饰符,表示只能被包中其他类访问void sayGoodbye () {System.out.println("Good bye!");}public static void main (String [ ] args) {PackageSample01 packageSample01 = new PackageSample01() ;packeageSampleo1.satHello();}

3-3 面向对象特性之封装

public class Algorithm {/** *  传入五个数,控制台打印升序结果*@param a 第一个数*@param b 第二个数*@param c 第三个数*@param d 第四个数*@param e 第五个数*/public void sort(int a,int b,int c, int d, int e) {//冒泡排序算法int[ ] arr = {a,b,c,d,e};for (int i = 0;i< arr.length - 1-i;i++) {for(int j = 0;j<arr.length - 1-i ; j++) {if(arr[ j ] > arr[j+i]) {int temp = arr[j] ;arr[j] = arr[j+1]arr[j+1] = temp;}  }  }for(int i = 0 ; i<arr.length; i++) {System.out.print(arr[i] + " ");}  }public static void main (String [ ] args) {Algorithm algorithm = new Algorithm();algorithm.sort (a:82,b:88,c:998,d:223,e:184);}

public class Sorter {public static void main (String [ ] args) {Algorithm algorithm = new Algorithm();algorithm.sort (a:77,b:91,c:37,d:66,e:102);}}

3-4 对成员变量进行读写封装

public class MobileNumber  {1 related promblepublic String owner; //所有者1 related promblepublic String areaCode = "86";//国家区号public long mobileNumber;//手机号//getter方法,getter方法用于读取成员变量的内容//getter书写格式,public成员变量类型, get成员变量名( ),PS:首字母大写public String getOwner( ) {//this 关键字代表当前对象的...return this.owner;}//setter方法,setter方法用于设置成员变量的内容//setter书写格式,Public void set成员变量名(新的数据参数)public void setOwner(String owner) {this.owner = owner;}}

public class MobileNumberTestor {public static void main(String [ ] args) {MobileNumber mobileNumber = new MobileNumber();//mobileNumber.owner = "老齐";//mobileNumber.areaCode = "84";}}

第四章面向对象特性之继承和多态

4-1 面向对象特性之继承

public class Mark1 {protected String title;protected String color;protected String movie;public void description() {System.out.println("型号:" + title);System.out.println("颜色:" + color);System.out.println("首次出现的电影:" + movie);}private void fire() {System.out.println("利用手臂燃料泵射出火焰")public static void main(String[ ] args) {Mark1 mark1 = new Mark1();mark1.color = "银灰色";mark1.movie = "钢铁侠1";mark1.description();mark1.fire;}}

/jextends关键字用于类的继承
//extends关键字后面是"父类"extends关键字前是"子类"
e//子类会继承父类的(default)/protected/public修饰的成员变量与方法public class Hulk extends Markl {public static void main(string[] args){Hulk hulk=new Hulk(); hulk.title="反浩克装甲";hulk.color="红色";hulk.movie="复仇者联盟3";hulk.description();}}

 //extends关键字用于类的继承 //extends关键字后面是"父类"extends关键字前是"子类" 
//子类会继承父类的(default)/protected/public修饰的成员变量与方法public class Hulk extends Markl { private void repair(){ 
System.out.println("弹射备件替换战损组件");public static void main(string[] args){
Hulk hulk=new Hulk();
hulk.title="反浩克装甲"; I 
hulk.color="红色";
hulk.movie="复仇者联盟3";hulk.description((); // hulk.fire(); hulk.repair();}
}


public class Mark85 extends Markl{
private void createShield(){
System.out.println("利用纳米技术生成防御护盾");}
public static void main(String[] args){
Mark85 mark85=newMark85(); 
mark85.title="马克85型";mark85.color="红色";
mark85.movie-"复仇者联盟4"; 
mark85.description();mark85.createShield();

4-2 面向对象特性之多态

public class Chinese implements Language{
@Override
public void voice() {
System.out.println("你好,有什么可以帮到您的?");
}
}

public class English implements Languagel
@Override
public void voice() {
System.out.println("Hi,may I help you?");
}
}

 public class French implements Language{ verride{
public void voice() {
System.out.println("Comment puis-je me rendre à l'h pital ?");
}
}

public class CustomerService {
public static void main(String[] args){
Language language=new English();language.voice();
}}


public class CustomerService {
public Language contact (int areaCode){if(areaCode==86){return new Chinese();
}else if(areaCode33){return new French();
}else{return new English();public static void main(String[] args){
Language language=new English();language.voice();
Language languagel=new Chinese();
languagel.voice();  
CustomerServicecs=new CustomerService; 
Language language2=cs.contact(areaCode:86); 
language2.voice();
)

import com.imooc.objectproject.sample5.system.CustomerService; importcom.imooc.objectprojectsample5.system.Language;
public class Customer {
public static void main(string[] args){
CustomerService customerService=new CustomerService(()
Language lanauaae =customerService.contact(areaCode:33);
language.voice();
}
}

4-4 Arraylist列表类的使用

import java.util.ArrayList;import java.util.list;
public class ArrayListSample{
public static void main(String[] args){
List bookList=new ArrayList();
}
}

import java.util.ArrayList;import java.util.list;
public class ArrayListSample{
public static void main(String[] args){
List bookList=new ArrayList(); 
bookList.add("红楼梦"); 
bookList.add("西游记"); 
bookList.add("水浒传"); 
bookList.add("三国志");
System.outprintln(bookList);
}}

import java.util.ArrayList;import java.util.list;
public class ArrayListSample{
public static void main(String[] args){
List bookList=new ArrayList(); 
bookList.add("红楼梦"); 
bookList.add("西游记"); 
bookList.add("水浒传"); 
bookList.add("三国志");
System.outprintln(bookList);bookList.add(index:0,element:"镜花缘");System.out.println(bookList);
}
}

public static void main(String[] args){
//泛型
List<string> bookList=newArraList<string>();bookList.add("红楼梦");bookList.add("西游记"); 
bookList.add("水浒传");bookList.add("三国志");
bookList.add(index:0，element"镜花缘");
System.out.println(bookList); 
String bookName = bookList.get(2);
System.out.println(bookName);
}