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.blueprint;
018
019 import java.lang.reflect.Modifier;
020 import java.util.List;
021 import java.util.Set;
022
023 import org.apache.camel.RoutesBuilder;
024 import org.apache.camel.spi.PackageScanClassResolver;
025 import org.osgi.service.blueprint.container.BlueprintContainer;
026 import org.osgi.service.blueprint.reflect.BeanMetadata;
027 import org.slf4j.Logger;
028 import org.slf4j.LoggerFactory;
029
030 /**
031 * A helper class which will find all {@link org.apache.camel.builder.RouteBuilder} instances on the classpath
032 *
033 * @version
034 */
035 public class PackageScanRouteBuilderFinder {
036 private static final Logger LOG = LoggerFactory.getLogger(PackageScanRouteBuilderFinder.class);
037 private final BlueprintCamelContext camelContext;
038 private final String[] packages;
039 private final PackageScanClassResolver resolver;
040 private final BlueprintContainer blueprintContainer;
041
042 public PackageScanRouteBuilderFinder(BlueprintCamelContext camelContext, String[] packages, ClassLoader classLoader,
043 PackageScanClassResolver resolver) {
044 this.camelContext = camelContext;
045 this.blueprintContainer = camelContext.getBlueprintContainer();
046 this.packages = packages;
047 this.resolver = resolver;
048 // add our provided loader as well
049 resolver.addClassLoader(classLoader);
050 }
051
052 /**
053 * Appends all the {@link org.apache.camel.builder.RouteBuilder} instances that can be found on the classpath
054 */
055 public void appendBuilders(List<RoutesBuilder> list) throws IllegalAccessException, InstantiationException {
056 Set<Class<?>> classes = resolver.findImplementations(RoutesBuilder.class, packages);
057 for (Class<?> aClass : classes) {
058 LOG.trace("Found RouteBuilder class: {}", aClass);
059
060 // certain beans should be ignored
061 if (shouldIgnoreBean(aClass)) {
062 LOG.debug("Ignoring RouteBuilder class: {}", aClass);
063 continue;
064 }
065
066 if (!isValidClass(aClass)) {
067 LOG.debug("Ignoring invalid RouteBuilder class: {}", aClass);
068 continue;
069 }
070
071 // type is valid so create and instantiate the builder
072 RoutesBuilder builder = instantiateBuilder(aClass);
073 LOG.debug("Adding instantiated RouteBuilder: {}", builder);
074 list.add(builder);
075 }
076 }
077
078 /**
079 * Allows for ignoring beans that are explicitly configured in the Spring XML files
080 */
081 protected boolean shouldIgnoreBean(Class<?> type) {
082 for (Object metadataObject : blueprintContainer.getMetadata(BeanMetadata.class)) {
083 BeanMetadata metadata = (BeanMetadata) metadataObject;
084 if (BeanMetadata.SCOPE_SINGLETON.equals(metadata.getScope())) {
085 Object bean = blueprintContainer.getComponentInstance(metadata.getId());
086 if (type.isInstance(bean)) {
087 return true;
088 }
089 }
090 }
091 return false;
092 }
093
094 /**
095 * Returns <tt>true</tt>if the class is a public, non-abstract class
096 */
097 protected boolean isValidClass(Class<?> type) {
098 // should skip non public classes
099 if (!Modifier.isPublic(type.getModifiers())) {
100 return false;
101 }
102
103 if (!Modifier.isAbstract(type.getModifiers()) && !type.isInterface()) {
104 return true;
105 }
106 return false;
107 }
108
109 protected RoutesBuilder instantiateBuilder(Class<?> type) throws IllegalAccessException, InstantiationException {
110 return (RoutesBuilder) camelContext.getInjector().newInstance(type);
111 }
112 }