Java中的静态变量错误

Question

我写了一个简单的类和3个测试如下：

package MyPackage;

public class Person {
    
    private static int PERSON_COUNTER = 0;
    
    public Person() {
        PERSON_COUNTER++;
    }
    
    public String hello(){
        return "Hello World";
    }
    
    public String helloName(String name) {
        return "Hello "+name;
    }
    
    public static int numberOfPersons() {
        return PERSON_COUNTER;
    }
    
}

个人测试。爪哇：

package Test;

import static org.junit.Assert.assertEquals;

import org.junit.Test;

import MyPackage.Person;

public class PersonTest {
    
    @Test
    public void testHello() {
        Person p = new Person();
        assertEquals("Hello World",p.hello());
    }
    
    @Test
    public void testHelloName() {
        Person p1 = new Person();
        assertEquals("Hello Mile",p1.helloName("Mile"));
    }
    
    @Test
    public void numberOfPersons() {
        Person p2 = new Person();
        Person p3 = new Person();
        Person p4 = new Person();
        assertEquals(3, Person.numberOfPersons());
    }
}

测试numberOfPersons失败，消息为：java。lang.AssertionError:预期：

Answer 1

您应该使用带有注释@beforeach的方法，通过重置变量来清理您的环境，我认为这就是您缺少的。