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 */ 017package org.apache.camel.util; 018 019import org.apache.camel.CamelContext; 020import org.apache.camel.Component; 021import org.apache.camel.spi.DataFormat; 022import org.apache.camel.spi.DataFormatFactory; 023import org.apache.camel.spi.Language; 024import org.slf4j.Logger; 025import org.slf4j.LoggerFactory; 026 027/** 028 * Some helper methods for new resolvers (like {@link org.apache.camel.spi.ComponentResolver}, {@link org.apache.camel.spi.DataFormatResolver}, etc.). 029 * 030 * @version 031 */ 032public final class ResolverHelper { 033 034 public static final String COMPONENT_FALLBACK_SUFFIX = "-component"; 035 036 public static final String DATA_FORMAT_FALLBACK_SUFFIX = "-dataformat"; 037 038 public static final String DATA_FORMAT_FACTORY_FALLBACK_SUFFIX = "-dataformat-factory"; 039 040 public static final String LANGUAGE_FALLBACK_SUFFIX = "-language"; 041 042 private static final Logger LOG = LoggerFactory.getLogger(ResolverHelper.class); 043 044 private static final LookupExceptionHandler EXCEPTION_HANDLER = new LookupExceptionHandler(); 045 046 /** 047 * Utility classes should not have a public constructor. 048 */ 049 private ResolverHelper() { 050 } 051 052 public static Component lookupComponentInRegistryWithFallback(CamelContext context, String name) { 053 return lookupComponentInRegistryWithFallback(context, name, EXCEPTION_HANDLER); 054 } 055 056 public static Component lookupComponentInRegistryWithFallback(CamelContext context, String name, LookupExceptionHandler exceptionHandler) { 057 Object bean = lookupInRegistry(context, Component.class, false, exceptionHandler, name, name + COMPONENT_FALLBACK_SUFFIX); 058 if (bean != null) { 059 if (bean instanceof Component) { 060 return (Component) bean; 061 } else { 062 // let's use Camel's type conversion mechanism to convert things like CamelContext 063 // and other types into a valid Component 064 Component component = CamelContextHelper.convertTo(context, Component.class, bean); 065 if (component != null) { 066 return component; 067 } 068 } 069 } 070 071 if (bean != null) { 072 LOG.debug("Found Component with incompatible class: {}", bean.getClass().getName()); 073 } 074 return null; 075 } 076 077 public static DataFormat lookupDataFormatInRegistryWithFallback(CamelContext context, String name) { 078 return lookupDataFormatInRegistryWithFallback(context, name, EXCEPTION_HANDLER); 079 } 080 081 public static DataFormat lookupDataFormatInRegistryWithFallback(CamelContext context, String name, LookupExceptionHandler exceptionHandler) { 082 Object bean = lookupInRegistry(context, DataFormat.class, false, exceptionHandler, name, name + DATA_FORMAT_FALLBACK_SUFFIX); 083 if (bean instanceof DataFormat) { 084 return (DataFormat) bean; 085 } 086 087 if (bean != null) { 088 LOG.debug("Found DataFormat with incompatible class: {}", bean.getClass().getName()); 089 } 090 return null; 091 } 092 093 public static DataFormatFactory lookupDataFormatFactoryInRegistryWithFallback(CamelContext context, String name) { 094 return lookupDataFormatFactoryInRegistryWithFallback(context, name, EXCEPTION_HANDLER); 095 } 096 097 public static DataFormatFactory lookupDataFormatFactoryInRegistryWithFallback(CamelContext context, String name, LookupExceptionHandler exceptionHandler) { 098 Object bean = lookupInRegistry(context, DataFormatFactory.class, false, exceptionHandler, name, name + DATA_FORMAT_FACTORY_FALLBACK_SUFFIX); 099 if (bean instanceof DataFormatFactory) { 100 return (DataFormatFactory) bean; 101 } 102 103 if (bean != null) { 104 LOG.debug("Found DataFormatFactory with incompatible class: {}", bean.getClass().getName()); 105 } 106 return null; 107 } 108 109 public static Language lookupLanguageInRegistryWithFallback(CamelContext context, String name) { 110 return lookupLanguageInRegistryWithFallback(context, name, EXCEPTION_HANDLER); 111 } 112 113 public static Language lookupLanguageInRegistryWithFallback(CamelContext context, String name, LookupExceptionHandler exceptionHandler) { 114 Object bean = lookupInRegistry(context, Language.class, false, exceptionHandler, name, name + LANGUAGE_FALLBACK_SUFFIX); 115 if (bean instanceof Language) { 116 return (Language) bean; 117 } 118 119 if (bean != null) { 120 LOG.debug("Found Language with incompatible class: {}", bean.getClass().getName()); 121 } 122 return null; 123 } 124 125 126 public static class LookupExceptionHandler { 127 128 public void handleException(Exception e, Logger log, String name) { 129 log.debug("Ignored error looking up bean: " + name, e); 130 } 131 132 } 133 134 private static Object lookupInRegistry(CamelContext context, Class<?> type, boolean lookupByNameAndType, LookupExceptionHandler exceptionHandler, String... names) { 135 for (String name : names) { 136 try { 137 Object bean; 138 if (lookupByNameAndType) { 139 bean = context.getRegistry().lookupByNameAndType(name, type); 140 } else { 141 bean = context.getRegistry().lookupByName(name); 142 } 143 LOG.debug("Lookup {} with name {} in registry. Found: {}", type.getSimpleName(), name, bean); 144 if (bean != null) { 145 return bean; 146 } 147 } catch (Exception e) { 148 exceptionHandler.handleException(e, LOG, name); 149 } 150 } 151 152 return null; 153 } 154 155}