我应该让程序给出宠物的数量,以及低于5磅、5-10磅和超过10磅的宠物数量的百分比。程序不断重复这些语句,我不知道为什么。在过去的几天里,我一直在研究这个问题,但我还是搞不懂。有时我好像把它修好了,但后来又发生了。有人能解释为什么会这样吗?我需要帮助。
import java.util.*;
import java.util.Collections;
import java.util.Comparator;
import java.lang.Object;
public class SetPetWeight
{
public static void main(String[] args) {
ArrayList<Pet> list = new ArrayList<Pet>();
String name;
String answer;
int age;
Double weight;
Scanner keyboard = new Scanner(System.in);
do
{
System.out.println("Enter a String for Pet name: ");
name = keyboard.next();
System.out.println("Enter an int for Pet age: ");
age = keyboard.nextInt();
if(age <= 0)
System.out.println("Error! Enter a real age");
System.out.println("Enter a double for Pet weight: ");
weight = keyboard.nextDouble();
if(weight <= 0)
System.out.println("Error! Enter a real weight");
do
{
System.out.println("Do you want to enter another pet? Y/N");
answer = keyboard.nextLine();
keyboard.nextLine();
} while (answer.equalsIgnoreCase("Y"));
} while (name.length() < 0 && age < 0 && weight < 0);
System.out.println("The weight is now sorted by weight!");
Collections.sort(list, Pet.SortByWeight);
for (Pet p2 : list)
p2.writeOutput();
int average1 = 0;
int average2 = 0;
int average3 = 0;
for (Pet p : list)
{
if(p.getWeight() >= 0 && p.getWeight() <= 5)
{
++average1;
}
else if(p.getWeight() >= 5 && p.getWeight() <= 10)
{
++average2;
}
else if(p.getWeight() > 10)
{
++average3;
}
System.out.println("The average of pets under 5 pounds:" + average1);
System.out.println("The average of pets between 5 and 10 pounds:" + average2);
System.out.println("The average of pets over 10 pounds:" + average3);
}
}
}
用于setpetweight类并正确编译并用于数组的pet类。
import java.util.*;
public class Pet {
private String name;
private Integer age; // in years
private double weight; // in pounds
public void writeOutput() {
System.out.println("Name: " + name);
System.out.println("Age: " + age + " years");
System.out.println("Weight: " + weight + " pounds");
}
public void set(String newName) {
name = newName;
// age and weight are unchanged.
}
public void set(int newAge) {
if (newAge <= 0) {
System.out.println("Error: illegal age.");
System.exit(0);
} else
age = newAge;
// name and weight are unchanged.
}
public void set(double newWeight) {
if (newWeight <= 0) {
System.out.println("Error: illegal weight.");
System.exit(0);
} else
weight = newWeight;
// name and age are unchanged.
}
public Pet(String name, int age, double weight) {
this.name = name;
this.age = age;
this.weight = weight;
}
public String getName() {
return name;
}
public int getAge() {
return age;
}
public double getWeight() {
return weight;
}
public static Comparator<Pet> SortByWeight = new Comparator<Pet>()
{
public int compare(Pet pet1, Pet pet2)
{
return (int)(pet1.getWeight() - pet2.getWeight());
}
};
}
2条答案
按热度按时间h7wcgrx31#
移动
keyboard.nextLine();
之后weight = keyboard.nextDouble();
使用悬挂的换行符。68bkxrlz2#
您可能需要做一些更改。1.每次你检索用户输入的宠物的名字,年龄和体重。您可能需要创建一个pet类型的对象来存储这些值,然后将其添加到arraylist中。在你问他们是否想再添一只宠物之前。2.移除外部do while循环,并将inter循环更改为包含“enterastringforpetname:”。3.还要检查输入的有效性。