我正在创建虚拟猫。用户应该能够对其进行命名，并具有与用户交互的三个类别，即健康，食物，幸福。范围是（最低）1-50（最高）。int值是30。理想情况下，用户应该可以通过交互作用来升高或降低类别。
如何创建此范围并将其声明为最大值50，将最小值声明为1？
我已经声明了这三个类别。
String catName;
int food = 30;
int health = 30;
int happiness = 30;
System.out.println(" type cat name");
catName = input.nextLine();
答案 0 :(得分：0)
是的，正如@MC Emperor在评论中所说的，Java是OO语言，因此您应该这样使用它。例如，您可以创建以下类（只是为您提供启动的起点）：
public class VirtualCat{
private int food;
//... other properties, constructors etc
// here validate the modification of the property
public void increaseFood(){
if(food + 1 > 50){
throw new Exception("Invalid value for food");
} else {
food ++;
}
}
public void decreaseFood(){
if(food - 1 < 1){
throw new Exception("Invalid value for food");
} else {
food --;
}
}
}
答案 1 :(得分：0)
对于有权访问Guava Java库的用户，请考虑：
https://guava.dev/releases/19.0/api/docs/com/google/common/collect/Range.html
答案 2 :(得分：0)
就像其他人已经写过的一样，Java是一种面向对象的编程语言，您应该利用它。
确保值保持在定义范围内的一种好方法是实现一种可以设置上限，下限和可变值的类型。一个基本的实现可能看起来像这样：
public class RangedValue {
private final int lowerLimit;
private final int upperLimit;
private int value;
public RangedValue(int lowerLimit, int upperLimit, int value) {
if (lowerLimit >= upperLimit) {
throw new IllegalArgumentException("The lowerLimit must be less " +
"than the upperLimit!");
}
this.lowerLimit = lowerLimit;
this.upperLimit = upperLimit;
this.value = RangedValue.ensureRange(value, upperLimit, lowerLimit);
}
/**
* Helper method to ensure that a value stays within the defined range.
*
* @param value The value to be kept in the defined range
* @param upperLimit The upper limit of the range
* @param lowerLimit The lower limit of the range
* @return The value or the lowerLimit or the upperLimit
*/
private static int ensureRange(int value, int upperLimit, int lowerLimit) {
if (value > upperLimit) {
return upperLimit;
} else if (value < lowerLimit) {
return lowerLimit;
}
return value;
}
public int increaseValueBy(int value) {
int increased = this.value + value;
this.value = RangedValue.ensureRange(increased, upperLimit, lowerLimit);
return this.value;
}
public int reduceValueBy(int value) {
return increaseValueBy(-value);
}
public int setValue(int value) {
return RangedValue.ensureRange(value, upperLimit, lowerLimit);
}
public int getLowerLimit() {
return lowerLimit;
}
public int getUpperLimit() {
return upperLimit;
}
public int getValue() {
return value;
}
}
然后您可以将此类用于现有代码：
RangedValue food = new RangedValue(0, 50, 30);
RangedValue health = new RangedValue(0, 50, 30);
RangedValue happiness = new RangedValue(0, 50, 30);
System.out.println(" type cat name");
catName = input.nextLine();
当然，您也可以在单独的类中定义猫，但这取决于您。
答案 3 :(得分：0)
我了解您是否刚开始使用Java。 编写程序的正确方法是使用OOP。那就是..创建Virtual Cat的对象：
public class VirtualCat {
private String catName;
private int food;
private int health;
private int happiness;
public VirtualCat(String catName){
this.catName = catName;
this.food = 30;
this.health = 30;
this.happiness = 30;
}
public String increaseFood(){
if(this.food+1 > 50)
return "Error. Food range is [1-50].";
else{
this.food++;
return "Food increased.";
}
}
public String increaseHealth(){
if(this.health+1 > 50)
return "Error. Health range is [1-50].";
else{
this.health++;
return "Health increased.";
}
}
public String increaseHappiness(){
if(this.happiness+1 > 50)
return "Error. Happiness range is [1-50].";
else{
this.happiness++;
return "Happiness increased.";
}
}
public String decreaseFood(){
if(this.food-1 < 0)
return "Error. Food range is [1-50].";
else{
this.food--;
return "Food decreased.";
}
}
public String decreaseHealth(){
if(this.health-1 < 0)
return "Error. Health range is [1-50].";
else{
this.health--;
return "Health decreased.";
}
}
public String decreaseHappiness(){
if(this.happiness-1 < 0)
return "Error. Happiness range is [1-50].";
else{
this.happiness--;
return "Happiness decreased.";
}
}
@Override
public String toString() {
return "VirtualCat{" + "catName=" + catName + ", food=" + food + ", health=" + health + ", happiness=" + happiness + '}';
}
}
因此，您的主程序必须像这样：
public static void main(String[] args) {
int answer = 1;
int increaseOrDecrease = 0;
VirtualCat virtualCat = new VirtualCat(JOptionPane.showInputDialog(null, "Please insert cat name"));
while(answer == 1){
System.out.println("Actual status for virtual cat: "+virtualCat.toString());
increaseOrDecrease = Integer.parseInt(JOptionPane.showInputDialog(null, "Do you want to increase food? Type 1 for increase, type 2 for decrease"));
if(increaseOrDecrease == 1)
System.out.println(virtualCat.increaseFood());
else if(increaseOrDecrease == 2)
System.out.println(virtualCat.decreaseFood());
else
System.out.println("Incorrect option. It need to be 1 or 2");
increaseOrDecrease = Integer.parseInt(JOptionPane.showInputDialog(null, "Do you want to increase health? Type 1 for increase, type 2 for decrease"));
if(increaseOrDecrease == 1)
System.out.println(virtualCat.increaseHealth());
else if(increaseOrDecrease == 2)
System.out.println(virtualCat.decreaseHealth());
else
System.out.println("Incorrect option. It need to be 1 or 2");
increaseOrDecrease = Integer.parseInt(JOptionPane.showInputDialog(null, "Do you want to increase happiness? Type 1 for increase, type 2 for decrease"));
if(increaseOrDecrease == 1)
System.out.println(virtualCat.increaseHappiness());
else if(increaseOrDecrease == 2)
System.out.println(virtualCat.decreaseHappiness());
else
System.out.println("Incorrect option. It need to be 1 or 2");
answer = Integer.parseInt(JOptionPane.showInputDialog(null, "Do you want continue? Type 1 for yes, type 2 for no"));
}
System.out.print("Final status for virtual cat: "+virtualCat.toString());
}