Coverage Report - org.mule.registry.TypeBasedTransformerResolver
 
Classes in this File Line Coverage Branch Coverage Complexity
TypeBasedTransformerResolver
0%
0/59
0%
0/30
0
 
 1  
 /*
 2  
  * Copyright (c) MuleSoft, Inc.  All rights reserved.  http://www.mulesoft.com
 3  
  * The software in this package is published under the terms of the CPAL v1.0
 4  
  * license, a copy of which has been included with this distribution in the
 5  
  * LICENSE.txt file.
 6  
  */
 7  
 package org.mule.registry;
 8  
 
 9  
 import org.mule.api.MuleContext;
 10  
 import org.mule.api.MuleException;
 11  
 import org.mule.api.context.MuleContextAware;
 12  
 import org.mule.api.lifecycle.Disposable;
 13  
 import org.mule.api.lifecycle.Initialisable;
 14  
 import org.mule.api.lifecycle.InitialisationException;
 15  
 import org.mule.api.registry.ResolverException;
 16  
 import org.mule.api.registry.TransformerResolver;
 17  
 import org.mule.api.transformer.DataType;
 18  
 import org.mule.api.transformer.DiscoverableTransformer;
 19  
 import org.mule.api.transformer.Transformer;
 20  
 import org.mule.config.i18n.CoreMessages;
 21  
 import org.mule.transformer.TransformerChain;
 22  
 import org.mule.transformer.TransformerWeighting;
 23  
 import org.mule.transformer.simple.ObjectToByteArray;
 24  
 import org.mule.transformer.simple.ObjectToString;
 25  
 import org.mule.transformer.types.SimpleDataType;
 26  
 
 27  
 import java.util.List;
 28  
 import java.util.Map;
 29  
 
 30  
 import edu.emory.mathcs.backport.java.util.concurrent.ConcurrentHashMap;
 31  
 
 32  
 import org.apache.commons.logging.Log;
 33  
 import org.apache.commons.logging.LogFactory;
 34  
 
 35  
 /**
 36  
  * Will discover transformers based on type information only. It looks for transformers that support
 37  
  * the source and result types passed into the method. This resolver only resolves on the first
 38  
  * source type, which is the way transformer resolution working in Mule 2.x.
 39  
  */
 40  0
 public class TypeBasedTransformerResolver implements TransformerResolver, MuleContextAware, Disposable, Initialisable
 41  
 {
 42  
     /**
 43  
      * logger used by this class
 44  
      */
 45  0
     protected transient final Log logger = LogFactory.getLog(TypeBasedTransformerResolver.class);
 46  
 
 47  
     private ObjectToString objectToString;
 48  
     private ObjectToByteArray objectToByteArray;
 49  
 
 50  
     private MuleContext muleContext;
 51  
 
 52  0
     protected Map<String, Transformer> exactTransformerCache = new ConcurrentHashMap/*<String, Transformer>*/(8);
 53  
 
 54  
 
 55  
     public void setMuleContext(MuleContext context)
 56  
     {
 57  0
         this.muleContext = context;
 58  0
     }
 59  
 
 60  
     public void initialise() throws InitialisationException
 61  
     {
 62  
         try
 63  
         {
 64  0
             objectToString = new ObjectToString();
 65  0
             objectToByteArray = new ObjectToByteArray();
 66  0
             muleContext.getRegistry().applyProcessorsAndLifecycle(objectToString);
 67  0
             muleContext.getRegistry().applyProcessorsAndLifecycle(objectToByteArray);
 68  
         }
 69  0
         catch (MuleException e)
 70  
         {
 71  0
             throw new InitialisationException(e, this);
 72  0
         }
 73  0
     }
 74  
 
 75  
     public Transformer resolve(DataType source, DataType result) throws ResolverException
 76  
     {
 77  0
         Transformer transformer = exactTransformerCache.get(source.toString() + result.toString());
 78  0
         if (transformer != null)
 79  
         {
 80  0
             return transformer;
 81  
         }
 82  
 
 83  0
         List<Transformer> trans = muleContext.getRegistry().lookupTransformers(source, result);
 84  
 
 85  0
         transformer = getNearestTransformerMatch(trans, source.getType(), result.getType());
 86  
         //If an exact mach is not found, we have a 'second pass' transformer that can be used to converting to String or
 87  
         //byte[]
 88  
         Transformer secondPass;
 89  
 
 90  0
         if (transformer == null)
 91  
         {
 92  
             //If no transformers were found but the outputType type is String or byte[] we can perform a more general search
 93  
             // using Object.class and then convert to String or byte[] using the second pass transformer
 94  0
             if (result.getType().equals(String.class))
 95  
             {
 96  0
                 secondPass = objectToString;
 97  
             }
 98  0
             else if (result.getType().equals(byte[].class))
 99  
             {
 100  0
                 secondPass = objectToByteArray;
 101  
             }
 102  
             else
 103  
             {
 104  0
                 return null;
 105  
             }
 106  
             //Perform a more general search
 107  0
             trans = muleContext.getRegistry().lookupTransformers(source, new SimpleDataType(Object.class));
 108  
 
 109  0
             transformer = getNearestTransformerMatch(trans, source.getType(), result.getType());
 110  0
             if (transformer != null)
 111  
             {
 112  0
                 transformer = new TransformerChain(transformer, secondPass);
 113  
                 try
 114  
                 {
 115  0
                     muleContext.getRegistry().registerTransformer(transformer);
 116  
                 }
 117  0
                 catch (MuleException e)
 118  
                 {
 119  0
                     throw new ResolverException(e.getI18nMessage(), e);
 120  0
                 }
 121  
             }
 122  
         }
 123  
 
 124  0
         if (transformer != null)
 125  
         {
 126  0
             exactTransformerCache.put(source.toString() + result.toString(), transformer);
 127  
         }
 128  0
         return transformer;
 129  
     }
 130  
 
 131  
     protected Transformer getNearestTransformerMatch(List<Transformer> trans, Class input, Class output) throws ResolverException
 132  
     {
 133  0
         if (trans.size() > 1)
 134  
         {
 135  0
             if (logger.isDebugEnabled())
 136  
             {
 137  0
                 logger.debug("Comparing transformers for best match: input = " + input + " output = " + output + " Possible transformers = " + trans);
 138  
             }
 139  0
             TransformerWeighting weighting = null;
 140  0
             for (Transformer transformer : trans)
 141  
             {
 142  0
                 TransformerWeighting current = new TransformerWeighting(input, output, transformer);
 143  0
                 if (weighting == null)
 144  
                 {
 145  0
                     weighting = current;
 146  
                 }
 147  
                 else
 148  
                 {
 149  0
                     int compare = current.compareTo(weighting);
 150  0
                     if (compare == 1)
 151  
                     {
 152  0
                         weighting = current;
 153  
                     }
 154  0
                     else if (compare == 0)
 155  
                     {
 156  
                         //We may have two transformers that are exactly the same, in which case we can use either i.e. use the current
 157  0
                         if (!weighting.getTransformer().getClass().equals(current.getTransformer().getClass()))
 158  
                         {
 159  0
                             throw new ResolverException(CoreMessages.transformHasMultipleMatches(input, output,
 160  
                                     current.getTransformer(), weighting.getTransformer()));
 161  
                         }
 162  
                     }
 163  
                 }
 164  0
             }
 165  0
             return weighting.getTransformer();
 166  
         }
 167  0
         else if (trans.size() == 0)
 168  
         {
 169  0
             return null;
 170  
         }
 171  
         else
 172  
         {
 173  0
             return trans.get(0);
 174  
         }
 175  
     }
 176  
 
 177  
     public void dispose()
 178  
     {
 179  0
         exactTransformerCache.clear();
 180  0
     }
 181  
 
 182  
     public void transformerChange(Transformer transformer, RegistryAction registryAction)
 183  
     {
 184  0
         if (transformer instanceof DiscoverableTransformer)
 185  
         {
 186  0
             exactTransformerCache.clear();
 187  
         }
 188  0
     }
 189  
 }