Java操作考试:List,for,foreach,迭代器循环3种循环打印商品类内容【诗书画唱】
注意事项:
Ctrl+shift+F:整理代码格式。
类的首字母大小。
快速代码版(从写类时开始计时)
可以自己取其中的大写字母的类名的首字母为变量名,有时可以用上Alt+/的快速生成代码,用P1,P2的等命名。
Alt+/:





package A;
public class P {
private String name;
private Double price;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Double getPrice() {
return price;
}
public void setPrice(Double price) {
this.price = price;
}
public P(String name, Double price) {
super();
this.name = name;
this.price = price;
}
@Override
public String toString() {
return "P [name=" + name + ", price=" + price + "]";
}
}


package A;
import java.util.*;
public class D {
public static void main(String[] args) {
// TODO Auto-generated method stub
List<P> L=new ArrayList<P>();
P P1= new P("1", 1.1);
P P2= new P("2", 1.2);
L.add(P1);
L.add(P2);
for (P P : L) {
System.out.println(P);
}
Iterator<P> I= L.iterator() ;
while(I.hasNext()){
P P=I.next();
System.out.println(P);
}
for (int j = 0; j < L.size(); j++) {
P P=L.get(j);
System.out.println(P);
}
}
}


————————
有时要注意的,录音记忆的自己不熟的部分:
Iterator<Product> it = list.iterator();
ArrayList<Product>();
Product p
list.iterator();
it.hasNext()
it.next();
list.size();
list.get(i);



————————————
要求8分钟内自己敲代码写完:


package one;
public class Product {
private String name;
private Double price;
// 下面声明的传参的构造方法是为了在Text类中给商品类赋值:
public Product(String n,Double p) {
this.name = n;
this.price = p;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Double getPrice() {
return price;
}
public void setPrice(Double price) {
this.price = price;
}
//下面声明的toString方法是为了在Text类中能通过get
//等方法返回出:
@Override
public String toString() {
// TODO Auto-generated method stub
return "商品名称是:"
+ this.name
+ "商品价格是:¥"
+ this.price;
}
}


package one;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
public class Test {
public static void main(String[] args) {
// TODO Auto-generated method stub
List<Product>list = new ArrayList<Product>();
Product p1 = new Product("诗书画唱辣条",6.6);
Product p2 = new Product("诗书画唱瓜子",8.8);
Product p3 = new Product("诗书画唱巧克力",2.3);
list.add(p1);
list.add(p2);
list.add(p3);
//for循环:
System.out.println("\n下面是for循环:");
for(int i = 0;i < list.size();i ++) {
Product p = list.get(i);
System.out.println(p);
}
//foreach循环:
System.out.println("\n下面是foreach循环:");
for(Product p : list) {
System.out.println(p);
}
//迭代器循环:
System.out.println("\n下面是迭代器循环:");
Iterator<Product> it = list.iterator();
while(it.hasNext()) {
Product p = it.next();
System.out.println(p);
}
}
}

