io.cucumber.java.MethodScanner Maven / Gradle / Ivy
package io.cucumber.java;
import io.cucumber.core.logging.Logger;
import io.cucumber.core.logging.LoggerFactory;
import java.lang.annotation.Annotation;
import java.lang.reflect.Method;
import java.util.function.BiConsumer;
import static io.cucumber.core.resource.ClasspathSupport.classPathScanningExplanation;
import static io.cucumber.java.InvalidMethodException.createInvalidMethodException;
import static java.lang.reflect.Modifier.isAbstract;
import static java.lang.reflect.Modifier.isPublic;
import static java.lang.reflect.Modifier.isStatic;
final class MethodScanner {
private static final Logger log = LoggerFactory.getLogger(MethodScanner.class);
private MethodScanner() {
}
static void scan(Class aClass, BiConsumer consumer) {
// prevent unnecessary checking of Object methods
if (Object.class.equals(aClass)) {
return;
}
if (!isInstantiable(aClass)) {
return;
}
for (Method method : safelyGetMethods(aClass)) {
scan(consumer, aClass, method);
}
}
private static Method[] safelyGetMethods(Class aClass) {
try {
return aClass.getMethods();
} catch (NoClassDefFoundError e) {
log.warn(e,
() -> "Failed to load methods of class '" + aClass.getName() + "'.\n" + classPathScanningExplanation());
}
return new Method[0];
}
private static boolean isInstantiable(Class clazz) {
return isPublic(clazz.getModifiers())
&& !isAbstract(clazz.getModifiers())
&& (isStatic(clazz.getModifiers()) || clazz.getEnclosingClass() == null);
}
private static void scan(BiConsumer consumer, Class aClass, Method method) {
// prevent unnecessary checking of Object methods
if (Object.class.equals(method.getDeclaringClass())) {
return;
}
// exclude bridge methods: when a class implements a method
// from the interface but specializes the return type, two methods will
// be generated. One with the return type of the interface and one
// with the specialized return type. The former is a bridge method.
// Depending on the JVM, the method annotations are also applied to
// the bridge method.
if (method.isBridge()) {
return;
}
scan(consumer, aClass, method, method.getAnnotations());
}
private static void scan(
BiConsumer consumer, Class aClass, Method method, Annotation[] methodAnnotations
) {
for (Annotation annotation : methodAnnotations) {
if (isHookAnnotation(annotation) || isStepDefinitionAnnotation(annotation)) {
validateMethod(aClass, method);
consumer.accept(method, annotation);
} else if (isRepeatedStepDefinitionAnnotation(annotation)) {
scan(consumer, aClass, method, repeatedAnnotations(annotation));
}
}
}
private static void validateMethod(Class glueCodeClass, Method method) {
if (!glueCodeClass.equals(method.getDeclaringClass())) {
throw createInvalidMethodException(method, glueCodeClass);
}
}
private static boolean isHookAnnotation(Annotation annotation) {
Class annotationClass = annotation.annotationType();
return annotationClass.equals(Before.class)
|| annotationClass.equals(BeforeAll.class)
|| annotationClass.equals(After.class)
|| annotationClass.equals(AfterAll.class)
|| annotationClass.equals(BeforeStep.class)
|| annotationClass.equals(AfterStep.class)
|| annotationClass.equals(ParameterType.class)
|| annotationClass.equals(DataTableType.class)
|| annotationClass.equals(DefaultParameterTransformer.class)
|| annotationClass.equals(DefaultDataTableEntryTransformer.class)
|| annotationClass.equals(DefaultDataTableCellTransformer.class)
|| annotationClass.equals(DocStringType.class);
}
private static boolean isStepDefinitionAnnotation(Annotation annotation) {
Class annotationClass = annotation.annotationType();
return annotationClass.getAnnotation(StepDefinitionAnnotation.class) != null;
}
private static boolean isRepeatedStepDefinitionAnnotation(Annotation annotation) {
Class annotationClass = annotation.annotationType();
return annotationClass.getAnnotation(StepDefinitionAnnotations.class) != null;
}
private static Annotation[] repeatedAnnotations(Annotation annotation) {
try {
Method expressionMethod = annotation.getClass().getMethod("value");
return (Annotation[]) Invoker.invoke(annotation, expressionMethod);
} catch (NoSuchMethodException e) {
// Should never happen.
throw new IllegalStateException(e);
}
}
}