mysql - 线程 "main"java.lang.IncompatibleClassChangeError : Found class org. apache.hadoop.mapreduce.JobContext 中的异常，但接口(interface)是预期的

Question

我正在使用 hadoop 1.0.3 和 sqoop 1.4.6。我正在尝试将一个表从 MySQL 导入到 hdfs。我收到以下错误:

Exception in thread "main" java.lang.IncompatibleClassChangeError: Found class org.apache.hadoop.mapreduce.JobContext, but interface was expected
    at org.apache.sqoop.config.ConfigurationHelper.getJobNumMaps(ConfigurationHelper.java:65)
    at com.cloudera.sqoop.config.ConfigurationHelper.getJobNumMaps(ConfigurationHelper.java:36)
    at org.apache.sqoop.mapreduce.db.DataDrivenDBInputFormat.getSplits(DataDrivenDBInputFormat.java:125)
    at org.apache.hadoop.mapred.JobClient.writeNewSplits(JobClient.java:962)
    at org.apache.hadoop.mapred.JobClient.writeSplits(JobClient.java:979)
    at org.apache.hadoop.mapred.JobClient.access$600(JobClient.java:174)
    at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:897)
    at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:850)
    at java.security.AccessController.doPrivileged(Native Method)
    at javax.security.auth.Subject.doAs(Subject.java:422)
    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1121)
    at org.apache.hadoop.mapred.JobClient.submitJobInternal(JobClient.java:850)
    at org.apache.hadoop.mapreduce.Job.submit(Job.java:500)
    at org.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:530)
    at org.apache.sqoop.mapreduce.ImportJobBase.doSubmitJob(ImportJobBase.java:196)
    at org.apache.sqoop.mapreduce.ImportJobBase.runJob(ImportJobBase.java:169)
    at org.apache.sqoop.mapreduce.ImportJobBase.runImport(ImportJobBase.java:266)
    at org.apache.sqoop.manager.SqlManager.importTable(SqlManager.java:673)
    at org.apache.sqoop.manager.MySQLManager.importTable(MySQLManager.java:118)
    at org.apache.sqoop.tool.ImportTool.importTable(ImportTool.java:497)
    at org.apache.sqoop.tool.ImportTool.run(ImportTool.java:605)
    at org.apache.sqoop.Sqoop.run(Sqoop.java:143)
    at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:65)
    at org.apache.sqoop.Sqoop.runSqoop(Sqoop.java:179)
    at org.apache.sqoop.Sqoop.runTool(Sqoop.java:218)
    at org.apache.sqoop.Sqoop.runTool(Sqoop.java:227)
    at org.apache.sqoop.Sqoop.main(Sqoop.java:236)

对此有什么建议吗？

Answer 1

这是由于 sqoop 是在 hadoop 1.x 上编译的，您可以在 sqoop 站点上下载在 hadoop 2.x 上编译的 sqoop，转到链接 - 发布/sqoop 1应该看起来像这样，

sqoop-1.4.5.bin__hadoop-1.0.0.tar.gz
sqoop-1.4.5.bin__hadoop-2.0.4-alpha.tar.gz
获取 sqoop 或 hadoop2.x 应该可以解决问题。