001 /**
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.camel.spi;
018
019 import java.lang.annotation.Annotation;
020 import java.util.Set;
021
022 /**
023 * A resolver that can find resources based on package scanning.
024 */
025 public interface PackageScanClassResolver {
026
027 /**
028 * Sets the ClassLoader instances that should be used when scanning for
029 * classes. If none is set then the context classloader will be used.
030 *
031 * @param classLoaders loaders to use when scanning for classes
032 */
033 void setClassLoaders(Set<ClassLoader> classLoaders);
034
035 /**
036 * Gets the ClassLoader instances that should be used when scanning for classes.
037 *
038 * @return the class loaders to use
039 */
040 Set<ClassLoader> getClassLoaders();
041
042 /**
043 * Adds the class loader to the existing loaders
044 *
045 * @param classLoader the loader to add
046 */
047 void addClassLoader(ClassLoader classLoader);
048
049 /**
050 * Attempts to discover classes that are annotated with to the annotation.
051 *
052 * @param annotation the annotation that should be present on matching classes
053 * @param packageNames one or more package names to scan (including subpackages) for classes
054 * @return the classes found, returns an empty set if none found
055 */
056 Set<Class> findAnnotated(Class<? extends Annotation> annotation, String... packageNames);
057
058 /**
059 * Attempts to discover classes that are annotated with to the annotation.
060 *
061 * @param annotations the annotations that should be present (any of them) on matching classes
062 * @param packageNames one or more package names to scan (including subpackages) for classes
063 * @return the classes found, returns an empty set if none found
064 */
065 Set<Class> findAnnotated(Set<Class<? extends Annotation>> annotations, String... packageNames);
066
067 /**
068 * Attempts to discover classes that are assignable to the type provided. In
069 * the case that an interface is provided this method will collect
070 * implementations. In the case of a non-interface class, subclasses will be
071 * collected.
072 *
073 * @param parent the class of interface to find subclasses or implementations of
074 * @param packageNames one or more package names to scan (including subpackages) for classes
075 * @return the classes found, returns an empty set if none found
076 */
077 Set<Class> findImplementations(Class parent, String... packageNames);
078
079 /**
080 * Attemsp to discover classes filter by the provided filter
081 *
082 * @param fiter filter to filter desired classes.
083 * @param packageNames one or more package names to scan (including subpackages) for classes
084 * @return the classes found, returns an empty set if none found
085 */
086 Set<Class> findByFilter(PackageScanFilter fiter, String... packageNames);
087
088 }