在运行简单的 hadoop 程序中得到 class 转换异常

Question

我正在尝试从 eclipse 运行一个简单的 hadoop 程序，但出现以下异常。请帮助解决问题**

2019-09-02 21:32:13,528 WARN  [LocalJobRunner Map Task Executor #0] mapred.MapTask (MapTask.java:createSortingCollector(417)) - Unable to initialize MapOutputCollector org.apache.hadoop.mapred.MapTask$MapOutputBuffer
java.lang.ClassCastException: interface javax.xml.soap.Text
    at java.lang.Class.asSubclass(Unknown Source)
    at org.apache.hadoop.mapred.JobConf.getOutputKeyComparator(JobConf.java:903)
    at org.apache.hadoop.mapred.MapTask$MapOutputBuffer.init(MapTask.java:1018)
    at org.apache.hadoop.mapred.MapTask.createSortingCollector(MapTask.java:408)
    at org.apache.hadoop.mapred.MapTask.access0(MapTask.java:82)
    at org.apache.hadoop.mapred.MapTask$NewOutputCollector.<init>(MapTask.java:710)
    at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:782)
    at org.apache.hadoop.mapred.MapTask.run(MapTask.java:347)
    at org.apache.hadoop.mapred.LocalJobRunner$Job$MapTaskRunnable.run(LocalJobRunner.java:271)
    at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
    at java.util.concurrent.FutureTask.run(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

Answer 1

当您想导入 org.apache.hadoop.io.Text 时，您已经导入了 javax.xml.soap.Text。

在运行简单的 hadoop 程序中得到 class 转换异常

getting class cast exception while running simple hadoop program

hadoop

mapreduce

在 运行 简单的 hadoop 程序中得到 class 转换异常

getting class cast exception while running simple hadoop program

hadoop

mapreduce

在运行简单的 hadoop 程序中得到 class 转换异常