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.impl.converter;
018
019 import java.util.Map;
020 import java.util.Set;
021 import java.util.concurrent.atomic.AtomicBoolean;
022
023 import org.apache.camel.Exchange;
024 import org.apache.camel.TypeConverter;
025 import org.apache.camel.spi.FactoryFinder;
026 import org.apache.camel.spi.Injector;
027 import org.apache.camel.spi.PackageScanClassResolver;
028 import org.apache.camel.util.ObjectHelper;
029
030 /**
031 * Lazy implementation of a type converter registry used for
032 * <a href="http://camel.apache.org/type-converter.html">type converters</a> in Camel.
033 * <p/>
034 * This implementation will lazy load type converters on-demand.
035 *
036 * @version
037 * @deprecated will be removed in a future Camel release.
038 */
039 @Deprecated
040 public class LazyLoadingTypeConverter extends BaseTypeConverterRegistry {
041 private final AtomicBoolean loaded = new AtomicBoolean();
042
043 public LazyLoadingTypeConverter(PackageScanClassResolver resolver, Injector injector, FactoryFinder factoryFinder) {
044 super(resolver, injector, factoryFinder);
045 }
046
047 @Override
048 public boolean allowNull() {
049 return false;
050 }
051
052 @Override
053 protected Object doConvertTo(final Class<?> type, final Exchange exchange, final Object value, boolean tryConvert) {
054 Object answer = super.doConvertTo(type, exchange, value, tryConvert);
055 if (answer == null && !loaded.get()) {
056 // okay we could not convert, so try again, but load the converters up front
057 ensureLoaded();
058 answer = super.doConvertTo(type, exchange, value, tryConvert);
059 }
060 return answer;
061 }
062
063 @Override
064 public TypeConverter getTypeConverter(Class<?> toType, Class<?> fromType) {
065 TypeConverter answer = super.getTypeConverter(toType, fromType);
066 if (answer == null && !loaded.get()) {
067 // okay we could not convert, so try again, but load the converters up front
068 ensureLoaded();
069 answer = super.getTypeConverter(toType, fromType);
070 }
071 return answer;
072 }
073
074 @Override
075 public Set<Class<?>> getFromClassMappings() {
076 if (!loaded.get()) {
077 ensureLoaded();
078 }
079 return super.getFromClassMappings();
080 }
081
082 @Override
083 public Map<Class<?>, TypeConverter> getToClassMappings(Class<?> fromClass) {
084 if (!loaded.get()) {
085 ensureLoaded();
086 }
087 return super.getToClassMappings(fromClass);
088 }
089
090 @Override
091 public Map<TypeMapping, TypeConverter> getTypeMappings() {
092 if (!loaded.get()) {
093 ensureLoaded();
094 }
095 return super.getTypeMappings();
096 }
097
098 @Override
099 protected TypeConverter doLookup(Class<?> toType, Class<?> fromType, boolean isSuper) {
100 TypeConverter answer = super.doLookup(toType, fromType, isSuper);
101 if (answer == null && !loaded.get()) {
102 // okay we could not convert, so try again, but load the converters up front
103 ensureLoaded();
104 answer = super.doLookup(toType, fromType, isSuper);
105 }
106 return answer;
107 }
108
109 private synchronized void ensureLoaded() {
110 if (loaded.compareAndSet(false, true)) {
111 try {
112 super.loadTypeConverters();
113 } catch (Exception e) {
114 throw ObjectHelper.wrapRuntimeCamelException(e);
115 }
116 }
117 }
118
119 @Override
120 protected void doStart() throws Exception {
121 super.doStart();
122 // must load core type converters
123 loadCoreTypeConverters();
124 }
125
126 @Override
127 protected void doStop() throws Exception {
128 super.doStop();
129 // reset loaded flag
130 loaded.set(false);
131 }
132 }
133