Type mismatch in value from map: expected org.apache.hadoop.io.longWritable
hadoop 编译的程序的报错
执行了命令:
hadoop fs -put HTTP_20130313143750.dat /date.doc
hadoop jar MyDataCount.jar com.liuyang.hadoop.maven.mr.dc.DataCount /date.doc /dateOut
要实现统计报文数据的功能
解决方案:
(1)更改这个属性
// 设置Mapper相关属性
job.setMapperClass(DCManager.class);
job.setMapOutputKeyClass(Text.class);
job.setMapOutputValueClass(DataBean.class);
(2)还有这个属性
job.setReducerClass(DCReducer.class);
job.setOutputKeyClass(Text.class);
job.setOutputValueClass(DataBean.class);
这样就成功了
十年磨一剑,一剑破万法