Testing Android code with JUnit and the JDK

Question

I'm writing some POJO tests for my Android code.

I want to run them locally with the JDK (not with Dalvik on the emulator) - for speed, JUnit 4, Mockito, and being able to run headless without a device - so I have a separate "Java" project in Eclipse.

If the method I'm testing happens to reference anything from the Android SDK, e.g. android.util.Log, the test fails - this makes sense because android.jar isn't in the classpath. To reproduce I have this test case:

public class FooTests {
  @Test
  public void testFoo() {
    android.util.Log.d("x", "y");
  }
}

If I add android.jar explicitly to the test project's classpath, I get exceptions like

java.lang.RuntimeException: Stub!
  at android.util.Log.d(Log.java:7)
  at com.example.FooTests.testFoo(FooTests.java:39)
  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  ...
  at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

Is there a way to make the code work without mocking out every last bit of Android SDK dependency? Perhaps a mocked-out android.jar already exists?

EDIT: For now I ended up wrapping classes like android.util.Log and injecting them into the instances, for classic IOC-based testing. Scott's PowerMock suggestion is my next step when I'll need it.

LATER EDIT: Robolectric!

Answer 1

I had the same problem. I wanted to test simple POJOs locally.
Specifically, my code wanted to use android.util.Base64.
What I ended up doing was to use the SDK to install the Android 4 sources, and copied the android.util.Base64 class to my project.
Surprisingly enough, this worked.