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package org.mule.registry; |
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import org.mule.api.MuleContext; |
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import org.mule.api.MuleException; |
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import org.mule.api.context.MuleContextAware; |
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import org.mule.api.lifecycle.Disposable; |
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import org.mule.api.lifecycle.Initialisable; |
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import org.mule.api.lifecycle.InitialisationException; |
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import org.mule.api.registry.ResolverException; |
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import org.mule.api.registry.TransformerResolver; |
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import org.mule.api.transformer.DataType; |
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import org.mule.api.transformer.DiscoverableTransformer; |
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import org.mule.api.transformer.Transformer; |
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import org.mule.config.i18n.CoreMessages; |
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import org.mule.transformer.TransformerChain; |
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import org.mule.transformer.TransformerWeighting; |
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import org.mule.transformer.simple.ObjectToByteArray; |
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import org.mule.transformer.simple.ObjectToString; |
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import org.mule.transformer.types.SimpleDataType; |
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import java.util.List; |
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import java.util.Map; |
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import edu.emory.mathcs.backport.java.util.concurrent.ConcurrentHashMap; |
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import org.apache.commons.logging.Log; |
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import org.apache.commons.logging.LogFactory; |
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43 | 0 | public class TypeBasedTransformerResolver implements TransformerResolver, MuleContextAware, Disposable, Initialisable |
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{ |
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48 | 0 | protected transient final Log logger = LogFactory.getLog(TypeBasedTransformerResolver.class); |
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private ObjectToString objectToString; |
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private ObjectToByteArray objectToByteArray; |
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private MuleContext muleContext; |
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|
55 | 0 | protected Map<String, Transformer> exactTransformerCache = new ConcurrentHashMap(8); |
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public void setMuleContext(MuleContext context) |
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{ |
60 | 0 | this.muleContext = context; |
61 | 0 | } |
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|
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public void initialise() throws InitialisationException |
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{ |
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try |
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{ |
67 | 0 | objectToString = new ObjectToString(); |
68 | 0 | objectToByteArray = new ObjectToByteArray(); |
69 | 0 | muleContext.getRegistry().applyProcessorsAndLifecycle(objectToString); |
70 | 0 | muleContext.getRegistry().applyProcessorsAndLifecycle(objectToByteArray); |
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} |
72 | 0 | catch (MuleException e) |
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{ |
74 | 0 | throw new InitialisationException(e, this); |
75 | 0 | } |
76 | 0 | } |
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|
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public Transformer resolve(DataType source, DataType result) throws ResolverException |
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{ |
80 | 0 | Transformer transformer = exactTransformerCache.get(source.toString() + result.toString()); |
81 | 0 | if (transformer != null) |
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{ |
83 | 0 | return transformer; |
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} |
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|
86 | 0 | List<Transformer> trans = muleContext.getRegistry().lookupTransformers(source, result); |
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|
88 | 0 | transformer = getNearestTransformerMatch(trans, source.getType(), result.getType()); |
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Transformer secondPass; |
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|
93 | 0 | if (transformer == null) |
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{ |
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|
97 | 0 | if (result.getType().equals(String.class)) |
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{ |
99 | 0 | secondPass = objectToString; |
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} |
101 | 0 | else if (result.getType().equals(byte[].class)) |
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{ |
103 | 0 | secondPass = objectToByteArray; |
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} |
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else |
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{ |
107 | 0 | return null; |
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} |
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|
110 | 0 | trans = muleContext.getRegistry().lookupTransformers(source, new SimpleDataType(Object.class)); |
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|
112 | 0 | transformer = getNearestTransformerMatch(trans, source.getType(), result.getType()); |
113 | 0 | if (transformer != null) |
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{ |
115 | 0 | transformer = new TransformerChain(transformer, secondPass); |
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try |
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{ |
118 | 0 | muleContext.getRegistry().registerTransformer(transformer); |
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} |
120 | 0 | catch (MuleException e) |
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{ |
122 | 0 | throw new ResolverException(e.getI18nMessage(), e); |
123 | 0 | } |
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} |
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} |
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|
127 | 0 | if (transformer != null) |
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{ |
129 | 0 | exactTransformerCache.put(source.toString() + result.toString(), transformer); |
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} |
131 | 0 | return transformer; |
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} |
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|
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protected Transformer getNearestTransformerMatch(List<Transformer> trans, Class input, Class output) throws ResolverException |
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{ |
136 | 0 | if (trans.size() > 1) |
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{ |
138 | 0 | if (logger.isDebugEnabled()) |
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{ |
140 | 0 | logger.debug("Comparing transformers for best match: input = " + input + " output = " + output + " Possible transformers = " + trans); |
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} |
142 | 0 | TransformerWeighting weighting = null; |
143 | 0 | for (Transformer transformer : trans) |
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{ |
145 | 0 | TransformerWeighting current = new TransformerWeighting(input, output, transformer); |
146 | 0 | if (weighting == null) |
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{ |
148 | 0 | weighting = current; |
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} |
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else |
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{ |
152 | 0 | int compare = current.compareTo(weighting); |
153 | 0 | if (compare == 1) |
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{ |
155 | 0 | weighting = current; |
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} |
157 | 0 | else if (compare == 0) |
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{ |
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|
160 | 0 | if (!weighting.getTransformer().getClass().equals(current.getTransformer().getClass())) |
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{ |
162 | 0 | throw new ResolverException(CoreMessages.transformHasMultipleMatches(input, output, |
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current.getTransformer(), weighting.getTransformer())); |
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} |
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} |
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} |
167 | 0 | } |
168 | 0 | return weighting.getTransformer(); |
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} |
170 | 0 | else if (trans.size() == 0) |
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{ |
172 | 0 | return null; |
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} |
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else |
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{ |
176 | 0 | return trans.get(0); |
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} |
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} |
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|
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public void dispose() |
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{ |
182 | 0 | exactTransformerCache.clear(); |
183 | 0 | } |
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|
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public void transformerChange(Transformer transformer, RegistryAction registryAction) |
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{ |
187 | 0 | if (transformer instanceof DiscoverableTransformer) |
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{ |
189 | 0 | exactTransformerCache.clear(); |
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} |
191 | 0 | } |
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} |