java - 如何在构造函数中设置@Value的值以进行测试

Question

这个问题已经有答案了:

Populating Spring @Value during Unit Test (13 个回答)

已关闭 3 年前。

我想将“ignore”值设置为 true 和 false。目前已经能够在 @Before 将其设置为 true。但我怎样才能通过将其设置为 false 来进行测试。请注意，我需要将其作为构造函数初始化。

由于在构造函数中设置了值，因此通过 ReflectionTestUtils 设置值将不起作用。我可以再次调用构造函数并将值设置为 false，但这将涉及此测试类中的大量设置以及所有相关的模拟等等，这会变得困惑。有没有解决的办法？

我有以下构造函数

// many other variables not relevant for this question
private final boolean ignore;

public Client(@Value("${a.error}") boolean ignore) {
    // setting many other variables not relevant for this question
    this.ignore = ignore;
}

测试时:

@Before
public void setUp() {
    client = new Client(true);
    //many other setups
}

// tests correctly fine cos I set the ignore to true
@Test
public void testing(){
    // someMethod uses the ignore value to do some actions and return true / false
    assertTrue(client.someMethod());
}

@Test
public void howToTestIgnoreSetToFalse(){
    // ? 
}

Answer 1

我可以在这里建议 3 个解决方案:

1. 使用 Spring 的 ReflectionUtils

@Before
public void setUp() {
    client = new Client(true);
    // rest of initialization
}

@Test
public void testing(){
    assertTrue(client.someMethod());
}

@Test
public void howToTestIgnoreSetToFalse(){
    Field fieldIgnore = Client.class.getDeclaredField("ignore");
    ReflectionUtils.makeAccessible(fieldIgnore);
    ReflectionUtils.setField(fieldIgnore, client, false);

    assertFalse(client.someMethod());
}

使用默认的 Reflection API

@Test
public void howToTestIgnoreSetToFalse(){
    Field fieldIgnore = Client.class.getDeclaredField("ignore");
    // only the way of how you're initializing field is changed,
    // everything else is the same
    fieldIgnore.setAccessible(true);
    Field modifiersField = Field.class.getDeclaredField("modifiers");
    modifiersField.setAccessible(true);
    modifiersField.setInt(f, f.getModifiers() & ~Modifier.FINAL);
    fieldIgnore.set(client, false);

    assertFalse(client.someMethod());
}

将初始化提取到单独的方法

// setup method doesn't required anymore

@Test
public void testing(){
    Client client = createClient(true);
    assertTrue(client.someMethod());
}

@Test
public void howToTestIgnoreSetToFalse(){
    Client client = createClient(false);
    assertTrue(client.someMethod());
}

// factory method to prepare mocked/initialized instance
private static Client createClient(boolean ignore) {
    Client client = new Client(ignore);
    // do common initialization
    // setup your mocks
    return client;  
}

希望对你有帮助!