Unable to initialize MapOutputCollector錯誤解析

我們在運行MapReduce的時候，會報一個空指針的異常，後面的報錯原因是下面一堆東西，其實很簡單，是我們Driver端的Text的包導錯了

WARN org.apache.hadoop.mapred.MapTask.createSortingCollector() - Unable to initialize MapOutputCollector org.apache.hadoop.mapred.MapTask$MapOutputBuffer
java.lang.NullPointerException
	at org.apache.hadoop.mapred.MapTask$MapOutputBuffer.init(MapTask.java:1011)
	at org.apache.hadoop.mapred.MapTask.createSortingCollector(MapTask.java:402)
	at org.apache.hadoop.mapred.MapTask.access$100(MapTask.java:81)
	at org.apache.hadoop.mapred.MapTask$NewOutputCollector.<init>(MapTask.java:698)
	at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:770)
	at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
	at org.apache.hadoop.mapred.LocalJobRunner$Job$MapTaskRunnable.run(LocalJobRunner.java:243)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)

這個是錯誤的包

import com.sun.jersey.core.impl.provider.entity.XMLJAXBElementProvider.Text;

這個是正確的包

import org.apache.hadoop.io.Text;

一般情況下，改了之後就好了