Mocking in Android

Question

I'm attempting to test the isKeyguardSecure() method of the KeyguardManager class in an Android application.

I've tried and failed using EasyMock , Mockito , and PowerMock to create a mock KeyguardManager object. Below are my attempts and the error messages received.

---

EasyMock

KeyguardManager keyguardManagerMock = EasyMock.createMock(KeyguardManager.class);

Error message: java.lang.IllegalArgumentException: android.app.KeyguardManager is not an interface

---

Mockito and PowerMock

KeyguardManager mockedKeyguardManager = Mockito.mock(KeyguardManager.class); KeyguardManager mockedKeyguardManager = PowerMockito.mock(KeyguardManager.class);

Error messages: java.lang.VerifyError: mockit/internal/startup/Startup java.lang.VerifyError: org/mockito/cglib/core/ReflectUtils

---

One explanation for this states that the root problem is with the Dalvik virtual machine that Android devices run. Can anyone verify this? Is it possible to mock the KeyguardManager class using any available mocking library that will work in testing an Android app?

Thanks!

Answer 1

Your EasyMock version is too old. PowerMock isn't required for that. Using EasyMock 3.4, I did the following and it worked perfectly:

public static void main(String[] args) {
    KeyguardManager manager = createMock(KeyguardManager.class);
    expect(manager.isKeyguardSecure()).andReturn(true);
    replay(manager);
    assertTrue(manager.isKeyguardSecure());
    verify(manager);
}

Answer 2

Use PowerMock with EasyMock.

Dependencies:

testCompile 'junit:junit:4.12'
testCompile 'org.easymock:easymock:3.3.1'
testCompile 'org.powermock:powermock-core:1.6.2'
testCompile 'org.powermock:powermock-api-easymock:1.6.2'
testCompile 'org.powermock:powermock-module-junit4:1.6.2'

Sample code:

package com.example.user.exampleapp;

import android.app.KeyguardManager;

import org.easymock.EasyMock;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.powermock.api.easymock.PowerMock;
import org.powermock.core.classloader.annotations.PrepareForTest;
import org.powermock.modules.junit4.PowerMockRunner;

@RunWith(PowerMockRunner.class)
@PrepareForTest(KeyguardManager.class)
public class KeyguardTest {

    @Test
    public void testKeyguard() {
        KeyguardManager keyguardMock = PowerMock.createMock(KeyguardManager.class);
        EasyMock.expect(keyguardMock.isKeyguardSecure()).andReturn(false);
        PowerMock.replayAll();
        System.out.println("is locked " + keyguardMock.isKeyguardSecure());
        PowerMock.verifyAll();
    }
}

Output:

is locked false