Java：实现Dog类年龄递增逻辑并通过单元测试（已解决）

需求说明 #

仅允许将狗的年龄递增，不可减少。在小型狗登记程序中，选择“增加狗年龄”选项时，无需用户输入，直接将当前年龄加1即可。

问题背景 #

最初实现的setAge方法无法通过单元测试，报错年龄未递增，改用increaseAgeByOne方法后解决了测试问题。

原setAge方法代码 #

public void setAge(int newAge) {
    if (newAge > this.age) {
        this.age = newAge;
    } else {
        System.out.println("Age cannot decrease. Keeping the current age.");
    }
}

解决测试问题的increaseAgeByOne方法代码 #

public void increaseAgeByOne() {
       if (age < Integer.MAX_VALUE) {
            age++;
        } else {
            System.out.println("Age cannot be increased further due to overflow.");
        }
    }

Dog类核心代码 #

public class Dog {
    private String name;
    private String breed;
    private int age;
    private int weight;
    private double tailLength;
    private static final double TAIL_LENGTH_FOR_DACHSHUND = 3.7;
    

    public Dog(String name, String breed, int age, int weight) {
        this.name = name;
        this.breed = breed;
        this.age = age;
        this.weight = weight;
        this.tailLength = tailLength;
        normalLetters();
    }

    public String getName() {
        return name;
    }

    public String getBreed() {
        return breed;
    }
    
    public int getAge() {
        return age;
    }

    public void setAge(int newAge) {
    if (newAge > this.age) {
        this.age = newAge;
    } else {
        System.out.println("Age cannot decrease. Keeping the current age.");
    }
}
    
   ...

    
}

对应的单元测试用例 #

@Test
    @Order(130)
    @DisplayName("Age can be updated")
    public void ableToIncreaseAge() {
        Dog dog;

        dog = new Dog(DEFAULT_NAME, DEFAULT_BREED, DEFAULT_AGE, DEFAULT_WEIGHT);
        callAssumedMethodForIncreasingAgeOfDog(dog, 1);
        assertEquals(DEFAULT_AGE + 1, dog.getAge());

        dog = new Dog(DEFAULT_NAME, DEFAULT_BREED, DEFAULT_AGE, DEFAULT_WEIGHT);
        callAssumedMethodForIncreasingAgeOfDog(dog, 3);
        assertEquals(DEFAULT_AGE + 3, dog.getAge());
    }

    @Test
    @Order(140)
    @DisplayName("Age cannot decrease")
    public void unableToDecreaseAge() {
        Dog dog;

        dog = new Dog(DEFAULT_NAME, DEFAULT_BREED, DEFAULT_AGE, DEFAULT_WEIGHT);
        callAssumedMethodForIncreasingAgeOfDog(dog, -1);
        assertEquals(DEFAULT_AGE, dog.getAge());
    }

    @Test
    @Order(150)
    @DisplayName("Age cannot decrease through overflow")
    public void unableToDecreaseAgeThroughOverflow() {
        Dog dog;

        dog = new Dog(DEFAULT_NAME, DEFAULT_BREED, Integer.MAX_VALUE, DEFAULT_WEIGHT);
        callAssumedMethodForIncreasingAgeOfDog(dog, 1);
        assertEquals(Integer.MAX_VALUE, dog.getAge());
    }

内容的提问来源于stack exchange，提问作者Teodora Kovacevic