Here is the complete stack -
Exception in thread "main" java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at
org.eclipse.jdt.internal.jarinjarloader.JarRsrcLoader.main(JarRsrcLoader.java:56)
Caused by: org.apache.mahout.cf.taste.common.TasteException:
java.lang.NullPointerException
at
org.apache.mahout.cf.taste.impl.eval.AbstractDifferenceRecommenderEvaluator.execute(AbstractDifferenceRecommenderEvaluator.java:209)
at
org.apache.mahout.cf.taste.impl.eval.AbstractDifferenceRecommenderEvaluator.getEvaluation(AbstractDifferenceRecommenderEvaluator.java:188)
at
org.apache.mahout.cf.taste.impl.eval.AbstractDifferenceRecommenderEvaluator.evaluate(AbstractDifferenceRecommenderEvaluator.java:132)
at
org.tsr.recommender.TSRRecommenderEvaluatorRunner.computeMAE(TSRRecommenderEvaluatorRunner.java:65)
at
org.tsr.recommender.TSRRecommenderEvaluatorRunner.main(TSRRecommenderEvaluatorRunner.java:40)
... 5 more
Caused by: java.lang.NullPointerException
at
org.apache.mahout.cf.taste.impl.similarity.file.FileItemSimilarity.itemSimilarities(FileItemSimilarity.java:109)
at
org.apache.mahout.cf.taste.impl.recommender.GenericItemBasedRecommender.doEstimatePreference(GenericItemBasedRecommender.java:195)
at
org.apache.mahout.cf.taste.impl.recommender.GenericItemBasedRecommender.estimatePreference(GenericItemBasedRecommender.java:126)
at
org.apache.mahout.cf.taste.impl.recommender.CachingRecommender$EstimatedPrefRetriever.get(CachingRecommender.java:214)
at
org.apache.mahout.cf.taste.impl.recommender.CachingRecommender$EstimatedPrefRetriever.get(CachingRecommender.java:1)
at
org.apache.mahout.cf.taste.impl.common.Cache.getAndCacheValue(Cache.java:127)
at org.apache.mahout.cf.taste.impl.common.Cache.get(Cache.java:96)
at
org.apache.mahout.cf.taste.impl.recommender.CachingRecommender.estimatePreference(CachingRecommender.java:128)
at
org.TSR.recommender.TSRRecommender.estimatePreference(TSRRecommender.java:391)
at
org.apache.mahout.cf.taste.impl.eval.AbstractDifferenceRecommenderEvaluator$PreferenceEstimateCallable.call(AbstractDifferenceRecommenderEvaluator.java:256)
at
org.apache.mahout.cf.taste.impl.eval.AbstractDifferenceRecommenderEvaluator$PreferenceEstimateCallable.call(AbstractDifferenceRecommenderEvaluator.java:1)
at
org.apache.mahout.cf.taste.impl.eval.AbstractDifferenceRecommenderEvaluator$StatsCallable.call(AbstractDifferenceRecommenderEvaluator.java:301)
at
org.apache.mahout.cf.taste.impl.eval.AbstractDifferenceRecommenderEvaluator$StatsCallable.call(AbstractDifferenceRecommenderEvaluator.java:1)
at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown
Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown
Source)
at java.lang.Thread.run(Unknown Source)
(Sorry for the late reply; I was travelling)
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