如何在java中使用Mockito模拟实例变量？

public class MyClass {
    private MyDependency myDependency;

    public void setMyDependency(MyDependency myDependency) {
        this.myDependency = myDependency;
    }

    public int performOperation() {
        // 使用myDependency执行一些操作
        return myDependency.doSomething();
    }
}

public class MyDependency {
    public int doSomething() {
        // 执行某些操作
        return 0;
    }
}

import org.junit.Test;
import org.mockito.Mockito;

import static org.junit.Assert.assertEquals;

public class MyClassTest {
    @Test
    public void testPerformOperation() {
        // 创建被模拟的实例变量
        MyDependency mockedDependency = Mockito.mock(MyDependency.class);

        // 设置模拟的行为
        Mockito.when(mockedDependency.doSomething()).thenReturn(5);

        // 创建被测试的类实例
        MyClass myClass = new MyClass();

        // 将模拟的实例变量注入到被测试类中
        myClass.setMyDependency(mockedDependency);

        // 执行测试操作
        int result = myClass.performOperation();

        // 验证结果
        assertEquals(5, result);
    }
}