hadoop 读取文件异常

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Error: java.lang.ClassCastException: org.apache.hadoop.io.LongWritable cannot be cast to org.apache.hadoop.io.Text
        at com.symbol.data.tech.consumer_hot.ConsumerHotMapper.map(ConsumerHotMapper.java:12)
        at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:145)
        at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:784)
        at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
        at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:168)
        at java.security.AccessController.doPrivileged(Native Method)
        at javax.security.auth.Subject.doAs(Subject.java:415)
        at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1642)

at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:163)

开始程序的job中加载文件是用 FileInputFormat.setInputPaths(job,inputPath);这个类只能读取一个文件当第一个文件是空值的时候读取的内容是空值就报以上的错误、后来我换成 MultipleInputs.addInputPath(job, new Path(args[0]),TextInputFormat.class,ConsumerHotMapper.class); 程序就正常运行

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