Java Executor服务并发问题

我正在学习Java中的multithreading。 我正在使用执行程序服务（可调用）因为我需要最终收集我的结果并在进一步之前将它们组合起来。 我实现了multithreading并抛出错误，这是一个type.cast错误。 只是为了让你知道，一旦multithreading工作，并且它不能工作。 对于每个线程返回类型是TreeMap。 而且他们之间没有依赖关系。 这是我的实现：

class AbnerCallable implements Callable<TreeMap>{ TreeMap maps; AbnerCallable(TreeMap abs){ maps = abs; } @Override public TreeMap call() throws Exception { TreeMap nerRes = new TreeMap(); AbstractTagger nerTagger = new AbstractTagger(maps); nerRes = nerTagger.tagAbstracts(); System.out.println("######################One NER is finished."); return nerRes; } } public TreeMap NERmultithreading(TreeMap abstracts, int thread) throws InterruptedException, ExecutionException { ListOperations breakList = new ListOperations(); //variable to store sum TreeMap abnerResultA = new TreeMap(); ArrayList<TreeMap> abnerResultM = new ArrayList(); TreeMap abnerResult = new TreeMap(); ExecutorService executor = Executors.newFixedThreadPool(thread); List<Callable<TreeMap>> callableList = new ArrayList(); //Send abstract TreeMap for division in TreeMaps List divTreemap = breakList.divideTreemap(abstracts); //AbstractTagger nerTagger = new AbstractTagger(); System.out.println("Size of divTreeMap:"+divTreemap.size()); for (final TreeMap maps : divTreemap) { System.out.println("TreeMap: "+maps.size()); Object[] mapKey = maps.keySet().toArray(); Callable<TreeMap> nerCallable = new AbnerCallable(maps); callableList.add(nerCallable); } System.out.println("Size of callable: "+callableList.size()); //Returns after all tasks complete List<Future<TreeMap>> resFuture = executor.invokeAll(callableList); System.out.println("Size of future object: "+ resFuture.size()); //Print results as future objects for (Future<TreeMap> future : resFuture) { System.out.println("Status of future : " + future.isDone()); abnerResultA = future.get(); abnerResultM.add(abnerResultA); } executor.shutdown(); abnerResult = breakList.joinMaps(abnerResultM); System.out.println("Size of abner result: "+abnerResultM.size()); System.out.println("This is the abner map: "+abnerResultM); return abnerResult; } public List divideTreemap(TreeMap abstracts) { Object[] keyList = abstracts.keySet().toArray(); List dividedAbsList = new ArrayList(); // To hold multiple TreeMaps int size = abstracts.size(); System.out.println("Size:"+size); //System.out.println(abstracts); int divList = size / 4; int lastElement = divList-1; int firstElement = 0; System.out.println("Check Point:1"); for (int i = 1; i <= 4; i++) { System.out.println("i:"+i); if (i < 4) { TreeMap las = new TreeMap(abstracts.subMap(keyList[firstElement], true, keyList[lastElement], true)); dividedAbsList.add((las)); firstElement = lastElement+1; lastElement = lastElement + divList; } else { TreeMap las = new TreeMap(abstracts.subMap(keyList[firstElement], true, keyList[size-1], true)); dividedAbsList.add(las); } } return dividedAbsList; } 

这是parital输出的错误示例….

 Exception on pipe 27. java.lang.ArrayIndexOutOfBoundsException: 33860864 java.lang.ArrayIndexOutOfBoundsException: 33860864 at gnu.trove.TObjectIntHashMap.rehash(TObjectIntHashMap.java:171) at gnu.trove.THash.postInsertHook(THash.java:243) at gnu.trove.TObjectIntHashMap.put(TObjectIntHashMap.java:148) at edu.umass.cs.mallet.base.types.Alphabet.lookupIndex(Alphabet.java:107) at edu.umass.cs.mallet.base.types.AugmentableFeatureVector.(AugmentableFeatureVector.java:88) at edu.umass.cs.mallet.base.types.FeatureVectorSequence.(FeatureVectorSequence.java:39) at edu.umass.cs.mallet.base.pipe.TokenSequence2FeatureVectorSequence.pipe(TokenSequence2FeatureVectorSequence.java:60) at edu.umass.cs.mallet.base.pipe.SerialPipes.pipe(SerialPipes.java:141) at edu.umass.cs.mallet.base.pipe.SerialPipes.pipe(SerialPipes.java:217) at edu.umass.cs.mallet.base.types.Instance.(Instance.java:105) at edu.umass.cs.mallet.base.types.InstanceList.add(InstanceList.java:741) at de.bonn.limes.gcam.abner.MyTagger.doTagging(MyTagger.java:445) at de.bonn.limes.gcam.abner.MyTagger.getEntities(MyTagger.java:297) at de.bonn.limes.core.AbnerAnalysis.NERanalysis(AbnerAnalysis.java:91) at de.bonn.limes.core.AbstractTagger.tagAbstracts(AbstractTagger.java:61) at de.bonn.limes.core.ListOperations$AbnerCallable.call(ListOperations.java:48) at de.bonn.limes.core.ListOperations$AbnerCallable.call(ListOperations.java:37) at java.util.concurrent.FutureTask.run(FutureTask.java:266) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745) Loading external tagging module from '/home/peeyush/Documents/netbeans_projects/GCAM-1.0/dependencies/nlpba.crf'... Loading external tagging module from '/home/peeyush/Documents/netbeans_projects/GCAM-1.0/dependencies/nlpba.crf'... ######################One NER is finished. ######################One NER is finished. Exception in thread "main" java.util.concurrent.ExecutionException: java.lang.ClassCastException: edu.umass.cs.mallet.base.types.TokenSequence cannot be cast to edu.umass.cs.mallet.base.types.FeatureVectorSequence Size of future object: 4 Status of future : true at java.util.concurrent.FutureTask.report(FutureTask.java:122) at java.util.concurrent.FutureTask.get(FutureTask.java:192) at de.bonn.limes.core.ListOperations.NERmultithreading(ListOperations.java:88) at de.bonn.limes.core.Main.main(Main.java:208) Caused by: java.lang.ClassCastException: edu.umass.cs.mallet.base.types.TokenSequence cannot be cast to edu.umass.cs.mallet.base.types.FeatureVectorSequence at edu.umass.cs.mallet.base.fst.CRF4$State.transitionIterator(CRF4.java:1981) at edu.umass.cs.mallet.base.fst.Transducer$ViterbiPath.(Transducer.java:1080) at edu.umass.cs.mallet.base.fst.Transducer.viterbiPath(Transducer.java:994) at edu.umass.cs.mallet.base.fst.Transducer.viterbiPath(Transducer.java:986) at de.bonn.limes.gcam.abner.MyTagger.doTagging(MyTagger.java:458) at de.bonn.limes.gcam.abner.MyTagger.getEntities(MyTagger.java:297) at de.bonn.limes.core.AbnerAnalysis.NERanalysis(AbnerAnalysis.java:91) at de.bonn.limes.core.AbstractTagger.tagAbstracts(AbstractTagger.java:61) at de.bonn.limes.core.ListOperations$AbnerCallable.call(ListOperations.java:48) at de.bonn.limes.core.ListOperations$AbnerCallable.call(ListOperations.java:37) at java.util.concurrent.FutureTask.run(FutureTask.java:266) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at java.lang.Thread.run(Thread.java:745) 

当我在单线程上运行时，我想再添加一些这些错误不在那里的东西。 如果您需要更多信息，请与我们联系。 谢谢你的帮助提前。