java.lang.Exception: java.lang.ClassCastException: org.apache.hadoop.mapreduce.lib.input.TaggedInput

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java.lang.Exception: java.lang.ClassCastException: org.apache.hadoop.mapreduce.lib.input.TaggedInputSplit cannot be cast to org.apache.hadoop.mapreduce.lib.input.FileSplit
at org.apache.hadoop.mapred.LocalJobRunner$Job.runTasks(LocalJobRunner.java:462)
at org.apache.hadoop.mapred.LocalJobRunner$Job.run(LocalJobRunner.java:522)
Caused by: java.lang.ClassCastException: org.apache.hadoop.mapreduce.lib.input.TaggedInputSplit cannot be cast to org.apache.hadoop.mapreduce.lib.input.FileSplit
at com.zx.example7.IDFMap.map(IDFMap.java:16)
at com.zx.example7.IDFMap.map(IDFMap.java:1)
at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:146)
at org.apache.hadoop.mapreduce.lib.input.DelegatingMapper.run(DelegatingMapper.java:55)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:787)
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$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)

at java.lang.Thread.run(Thread.java:745)

错误分析：因为此类采用的输入格式是MultipleInputs,MultipleInputs.addInputPath(...);

(FileSplit)(context.getInputSplit());

在mapper中再使用上面的那种方式,就会报出一个类型转换错误,

解决方法:直接通过反射来获得TaggedInputSplit中的inputSplit.处理过程就不写了.

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