com.google.inject.internal.Annotations Maven / Gradle / Ivy
/**
* Copyright (C) 2006 Google Inc.
*
* 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 com.google.inject.internal;
import com.google.inject.BindingAnnotation;
import com.google.inject.Key;
import com.google.inject.ScopeAnnotation;
import com.google.inject.TypeLiteral;
import java.lang.annotation.Annotation;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.reflect.Member;
/**
* Annotation utilities.
*
* @author [email protected] (Bob Lee)
*/
public class Annotations {
/**
* Returns true if the given annotation is retained at runtime.
*/
public static boolean isRetainedAtRuntime(Class annotationType) {
Retention retention = annotationType.getAnnotation(Retention.class);
return retention != null && retention.value() == RetentionPolicy.RUNTIME;
}
/** Returns the scope annotation on {@code type}, or null if none is specified. */
public static Class findScopeAnnotation(
Errors errors, Class implementation) {
return findScopeAnnotation(errors, implementation.getAnnotations());
}
/** Returns the scoping annotation, or null if there isn't one. */
public static Class findScopeAnnotation(Errors errors, Annotation[] annotations) {
Class found = null;
for (Annotation annotation : annotations) {
if (annotation.annotationType().isAnnotationPresent(ScopeAnnotation.class)) {
if (found != null) {
errors.duplicateScopeAnnotations(found, annotation.annotationType());
} else {
found = annotation.annotationType();
}
}
}
return found;
}
public static boolean isScopeAnnotation(Class annotationType) {
return annotationType.isAnnotationPresent(ScopeAnnotation.class);
}
/**
* Adds an error if there is a misplaced annotations on {@code type}. Scoping
* annotations are not allowed on abstract classes or interfaces.
*/
public static void checkForMisplacedScopeAnnotations(
Class type, Object source, Errors errors) {
if (Classes.isConcrete(type)) {
return;
}
Class scopeAnnotation = findScopeAnnotation(errors, type);
if (scopeAnnotation != null) {
errors.withSource(type).scopeAnnotationOnAbstractType(scopeAnnotation, type, source);
}
}
/** Gets a key for the given type, member and annotations. */
public static Key getKey(TypeLiteral type, Member member, Annotation[] annotations,
Errors errors) throws ErrorsException {
int numErrorsBefore = errors.size();
Annotation found = findBindingAnnotation(errors, member, annotations);
errors.throwIfNewErrors(numErrorsBefore);
return found == null ? Key.get(type) : Key.get(type, found);
}
/**
* Returns the binding annotation on {@code member}, or null if there isn't one.
*/
public static Annotation findBindingAnnotation(
Errors errors, Member member, Annotation[] annotations) {
Annotation found = null;
for (Annotation annotation : annotations) {
if (annotation.annotationType().isAnnotationPresent(BindingAnnotation.class)) {
if (found != null) {
errors.duplicateBindingAnnotations(member,
found.annotationType(), annotation.annotationType());
} else {
found = annotation;
}
}
}
return found;
}
}