| /** |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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 org.apache.camel.impl; |
| |
| import java.io.IOException; |
| |
| import org.apache.camel.CamelContext; |
| import org.apache.camel.Component; |
| import org.apache.camel.NoFactoryAvailableException; |
| import org.apache.camel.spi.ComponentResolver; |
| import org.apache.camel.spi.FactoryFinder; |
| import org.apache.camel.util.CamelContextHelper; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * The default implementation of {@link ComponentResolver} which tries to find |
| * components by using the URI scheme prefix and searching for a file of the URI |
| * scheme name in the <b>META-INF/services/org/apache/camel/component/</b> |
| * directory on the classpath. |
| * |
| * @version |
| */ |
| public class DefaultComponentResolver implements ComponentResolver { |
| |
| public static final String RESOURCE_PATH = "META-INF/services/org/apache/camel/component/"; |
| private static final transient Logger LOG = LoggerFactory.getLogger(DefaultComponentResolver.class); |
| private FactoryFinder factoryFinder; |
| |
| @SuppressWarnings("unchecked") |
| public Component resolveComponent(String name, CamelContext context) { |
| // lookup in registry first |
| Object bean = null; |
| try { |
| bean = context.getRegistry().lookup(name); |
| getLog().debug("Found component: {} in registry: {}", name, bean); |
| } catch (Exception e) { |
| getLog().debug("Ignored error looking up bean: " + name, e); |
| } |
| if (bean != null) { |
| if (bean instanceof Component) { |
| return (Component) bean; |
| } else { |
| // lets use Camel's type conversion mechanism to convert things like CamelContext |
| // and other types into a valid Component |
| Component component = CamelContextHelper.convertTo(context, Component.class, bean); |
| if (component != null) { |
| return component; |
| } |
| } |
| // we do not throw the exception here and try to auto create a component |
| } |
| |
| // not in registry then use component factory |
| Class type; |
| try { |
| type = findComponent(name, context); |
| if (type == null) { |
| // not found |
| return null; |
| } |
| } catch (NoFactoryAvailableException e) { |
| return null; |
| } catch (Exception e) { |
| throw new IllegalArgumentException("Invalid URI, no Component registered for scheme: " + name, e); |
| } |
| |
| if (getLog().isDebugEnabled()) { |
| getLog().debug("Found component: {} via type: {} via: {}{}", new Object[]{name, type.getName(), factoryFinder.getResourcePath(), name}); |
| } |
| |
| // create the component |
| if (Component.class.isAssignableFrom(type)) { |
| return (Component) context.getInjector().newInstance(type); |
| } else { |
| throw new IllegalArgumentException("Type is not a Component implementation. Found: " + type.getName()); |
| } |
| } |
| |
| private Class<?> findComponent(String name, CamelContext context) throws ClassNotFoundException, IOException { |
| if (factoryFinder == null) { |
| factoryFinder = context.getFactoryFinder(RESOURCE_PATH); |
| } |
| return factoryFinder.findClass(name); |
| } |
| |
| protected Logger getLog() { |
| return LOG; |
| } |
| |
| } |