Source: RulesListener.java 
package BetaMax.BetaMaxSample.extension;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import org.testng.IHookCallBack;
import org.testng.IHookable;
import org.testng.ITestContext;
import org.testng.ITestListener;
import org.testng.ITestNGMethod;
import org.testng.ITestResult;
public class RulesListener implements IHookable, ITestListener {
private static interface Function0<T> {
public void apply(T arg);
}
@Override
public void run(IHookCallBack callBack, ITestResult testResult) {
List<IHookable> hookables = getRules(testResult.getInstance(),
IHookable.class);
if (hookables.isEmpty()) {
callBack.runTestMethod(testResult);
} else {
IHookable hookable = hookables.get(0);
hookables.remove(0);
for (IHookable iHookable : hookables) {
hookable = compose(hookable, iHookable);
}
hookable.run(callBack, testResult);
}
}
private IHookable compose(final IHookable first, final IHookable second) {
return new IHookable() {
@Override
public void run(final IHookCallBack callBack,
final ITestResult testResult) {
first.run(new IHookCallBack() {
@Override
public void runTestMethod(ITestResult testResult) {
second.run(callBack, testResult);
}
@Override
public Object[] getParameters() {
return callBack.getParameters();
}
}, testResult);
}
};
}
private <T> List<T> getRules(Object object, Class<T> type) {
List<T> rules = new ArrayList<T>();
Field[] declaredFields = object.getClass().getFields();
for (Field field : declaredFields) {
NGRule annotation = field.getAnnotation(NGRule.class);
if (annotation != null) {
try {
Object fieldContent = field.get(object);
if (type.isAssignableFrom(field.getType())) {
@SuppressWarnings("unchecked")
T rule = (T) fieldContent;
rules.add(rule);
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
return rules;
}
@Override
public void onTestStart(final ITestResult result) {
executeRulesForInstance(new Function0<ITestListener>() {
@Override
public void apply(ITestListener listener) {
listener.onTestStart(result);
}
}, result.getInstance());
}
@Override
public void onTestSuccess(final ITestResult result) {
executeRulesForInstance(new Function0<ITestListener>() {
@Override
public void apply(ITestListener listener) {
listener.onTestSuccess(result);
}
}, result.getInstance());
}
@Override
public void onTestFailure(final ITestResult result) {
executeRulesForInstance(new Function0<ITestListener>() {
@Override
public void apply(ITestListener listener) {
listener.onTestFailure(result);
}
}, result.getInstance());
}
@Override
public void onTestSkipped(final ITestResult result) {
executeRulesForInstance(new Function0<ITestListener>() {
@Override
public void apply(ITestListener listener) {
listener.onTestSkipped(result);
}
}, result.getInstance());
}
@Override
public void onTestFailedButWithinSuccessPercentage(final ITestResult result) {
executeRulesForInstance(new Function0<ITestListener>() {
@Override
public void apply(ITestListener listener) {
listener.onTestFailedButWithinSuccessPercentage(result);
}
}, result.getInstance());
}
@Override
public void onStart(final ITestContext context) {
executeRulesForContext(context,
new Function0<ITestListener>() {
@Override
public void apply(ITestListener listener) {
listener.onStart(context);
}
});
}
@Override
public void onFinish(final ITestContext context) {
executeRulesForContext(context, new Function0<ITestListener>() {
@Override
public void apply(ITestListener listener) {
listener.onFinish(context);
}
});
}
private void executeRulesForContext(ITestContext context,
Function0<ITestListener> action) {
ITestNGMethod[] allTestMethods = context.getAllTestMethods();
Set<Object> testInstances = new HashSet<Object>();
for (ITestNGMethod iTestNGMethod : allTestMethods) {
testInstances.addAll(Arrays.asList(iTestNGMethod.getInstances()));
}
for (Object instance : testInstances) {
executeRulesForInstance(action, instance);
}
}
private void executeRulesForInstance(Function0<ITestListener> action,
Object allInst) {
List<ITestListener> hookables = getRules(allInst, ITestListener.class);
for (ITestListener listener : hookables) {
action.apply(listener);
}
}
}
