AndroidJUnit4Builder.java
/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.test.internal.runner.junit4;
import android.util.Log;
import androidx.test.internal.runner.EmptyTestRunner;
import androidx.test.internal.util.AndroidRunnerParams;
import java.lang.reflect.Method;
import org.junit.Test;
import org.junit.internal.builders.JUnit4Builder;
import org.junit.runner.Runner;
import org.junit.runners.model.RunnerBuilder;
/**
* A {@link RunnerBuilder} that will build customized runners needed to handle the ability to skip
* test execution if needed.
*/
public class AndroidJUnit4Builder extends JUnit4Builder {
private static final String TAG = "AndroidJUnit4Builder";
private final AndroidRunnerParams androidRunnerParams;
/** @param runnerParams {@link AndroidRunnerParams} that stores common runner parameters */
public AndroidJUnit4Builder(AndroidRunnerParams runnerParams) {
androidRunnerParams = runnerParams;
}
@Override
public Runner runnerForClass(Class<?> testClass) throws Throwable {
try {
if (!hasTestMethods(testClass)) {
// if we can't find any test methods, see if it's due to something with a custom classloader
if (testClass.getClassLoader() != Test.class.getClassLoader()) {
// ClassLoader#findClass(module, name) not available in Android
Class<?> clazz;
try {
clazz = Class.forName("org.junit.Test", false, testClass.getClassLoader());
} catch (Throwable e) {
clazz = Test.class;
}
if (!clazz.equals(Test.class)) {
return new EmptyTestRunner(
testClass,
new IllegalStateException(
"org.junit.Test in custom classloader "
+ testClass.getClassLoader()
+ " differs from org.junit.Test in the JUnit"
+ " runner's classloader. This causes JUnit to not be able to find the"
+ " tests to run."));
}
}
// return a special error runner if there are no @Test methods. This error runner will be
// ignored when classpath scanning
return new EmptyTestRunner(testClass);
}
return new AndroidJUnit4ClassRunner(testClass, androidRunnerParams);
} catch (Throwable e) {
// log error message including stack trace before throwing to help with debugging.
Log.e(TAG, "Error constructing runner", e);
throw e;
}
}
private static boolean hasTestMethods(Class<?> testClass) {
boolean hasTestMethods = false;
try {
for (Method testMethod : testClass.getMethods()) {
if (testMethod.isAnnotationPresent(org.junit.Test.class)) {
hasTestMethods = true;
break;
}
}
} catch (Throwable t) {
// Defensively catch everything - Will throw runtime exception if it cannot
// load methods.
//
// For earlier versions of Android (Pre-ICS), Dalvik might try to initialize a class
// during getMethods(), fail to do so, hide the error and throw a NoSuchMethodException.
// Since the java.lang.Class.getMethods does not declare such an exception, resort to a
// generic catch all.
// For ICS+, Dalvik will throw a NoClassDefFoundException.
Log.w(TAG, String.format("%s in hasTestMethods for %s", t.toString(), testClass.getName()));
return false;
}
return hasTestMethods;
}
}