我有一个 Android Activity ,其中有类似的调用
final ConnectToServerAsyncTask task = new ConnectToServerAsyncTask(...);
和
final Intent intent = new Intent(this, SomeActivity.class);
为了对此类进行单元测试,我需要能够模拟 ConnectToServerAsyncTask
和 Intent
的创建(例如使用 Mockito)。
还有比下面描述的更优雅的方法吗?
public class MainActivityOfTheApp extends Activity {
private IAsyncTaskFactory asyncTaskFactory = new AsyncTaskFactory();
private IIntentFactory intentFactory = new IntentFactory();
public void setAsyncTaskFactory(final IAsyncTaskFactory aFactory)
{
asyncTaskFactory = aFactory;
}
public void setIntentFactory(final IIntentFactory aFactory)
{
intentFactory = aFactory;
}
@Override
protected void onResume() {
...
final ConnectToServerAsyncTask task = asyncTaskFactory.create(...);
...
final Intent intent = intentFactory.create(this, OtherActivity.class);
...
}
}
在单元测试中,我将创建 MainActivityOfTheApp 的实例,然后使用 setAsyncTaskFactory
和 setIntentFactory
注入(inject)模拟。
最佳答案
PowerMock
您可以使用 PowerMock 模拟构造函数.
因此,在您的情况下,测试将如下所示:
@RunWith(PowerMockRunner.class)
@PrepareForTest(MainActivityOfTheApp.class)
public class MainActivityOfTheAppTest{
private AsyncTaskFactory asyncTaskFactory;
private IntentFactory intentFactory;
private MainActivityOfTheApp mainActivityOfTheApp;
@Before
public void prepare() {
asyncTaskFactory = PowerMockito.mock(AsyncTaskFactory.class);
intentFactory = PowerMockito.mock(IntentFactory.class);
PowerMockito.whenNew(AsyncTaskFactory.class).withNoArguments().thenReturn(asyncTaskFactory);
PowerMockito.whenNew(IntentFactory.class).withNoArguments().thenReturn(intentFactory);
mainActivityOfTheApp = new MainActivityOfTheApp();
}
@Test
public void doTest() {
//mainActivityOfTheApp has the mocks in final field inside, no need for the setters.
}
}
我必须指出,PowerMock 功能强大,但经常在复杂的类加载(例如 OSGI 环境)或代码覆盖工具(例如 jacoco)方面出现问题。它通常可以工作,但我已经浪费了一些时间。
没有 PowerMock
第二种可能性是创建 package private (没有修饰符。为什么不是 protected 或 public?请参阅 What's wrong with overridable method calls in constructors? )方法,它调用构造函数如下:
public class MainActivityOfTheApp extends Activity {
private final IAsyncTaskFactory asyncTaskFactory = constructAsyncTaskFactory();
private final IIntentFactory intentFactory = constructIntentFactory();
IAsyncTaskFactory constructAsyncTaskFactory()
{
return new AsyncTaskFactory();
}
IIntentFactory constructIntentFactory()
{
return new IntentFactory();
}
...
}
然后在你的单元测试中(测试必须与被测试的类位于同一个包中!)你重写construct*()方法:
public class MainActivityOfTheAppTest{
private AsyncTaskFactory asyncTaskFactory;
private IntentFactory intentFactory;
private MainActivityOfTheApp mainActivityOfTheApp;
@Before
public void prepare() {
asyncTaskFactory = mock(AsyncTaskFactory.class);
intentFactory = mock(IntentFactory.class);
mainActivityOfTheApp = new HackedMainActivityOfTheApp();
}
@Test
public void doTest() {
//mainActivityOfTheApp has the mocks in final field inside, no need for the setters.
}
private class HackedMainActivityOfTheApp extends MainActivityOfTheApp {
IAsyncTaskFactory constructAsyncTaskFactory()
{
return asyncTaskFactory;
}
IIntentFactory constructIntentFactory()
{
return intentFactory;
}
}
}
如果您对包含 MainActivityOfTheApp 的 jar 进行签名,则可以保护构造*方法。请参阅https://stackoverflow.com/a/968612/337621 :
Also, patches are harder (you have to re-sign the jar), class-patches are impossible (all classes in a single package must have the same signature source) and splitting jars becomes a chore.
关于java - 在 Android 代码中模拟创建 AsyncTasks 和 Intents 的优雅方法,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/17389466/