没有类名的ClassNotFoundException [英] ClassNotFoundException with no class name

问题描述

我尝试在一个jar中添加一个UDF并尝试LOAD。以下是我的片段

 
注册'target / warcbase-0.1.0-SNAPSHOT-fatjar.jar'; 
 
 DEFINE WarcLoader org.warcbase.pig.WarcLoader（）; 
 
 warc = LOAD'/ raw /'使用WarcLoader AS（网址：chararray，日期：chararray，mime：chararray，内容：bytearray）; 
 STORE warc INTO'/ raw / proc /'; 
 

我得到了下面的异常。不幸的是，它并没有告诉我哪个课程没有找到。以下是整个堆栈跟踪

 
后端错误消息
 -------------- ------- 
错误：java.io.IOException：java.lang.ClassNotFoundException：未找到类
，位于org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigSplit.readFields （PigSplit.java:236）
 at org.apache.hadoop.io.serializer.WritableSerialization $ WritableDeserializer.deserialize（WritableSerialization.java:71）
 at org.apache.hadoop.io.serializer.WritableSerialization $ WritableDeserializer.deserialize（WritableSerialization.java:42）
 at org.apache.hadoop.mapred.MapTask.getSplitDetails（MapTask.java:372）
 at org.apache.hadoop.mapred.MapTask.runNewMapper （MapTask.java:751）
 at org.apache.hadoop.mapred.MapTask.run（MapTask.java:341）
 at org.apache.hadoop.mapred.YarnChild $ 2.run（YarnChild。 java：163）
在java.security.AccessController.doPrivileged（本地方法）
在javax.security .auth.Subject.doAs（Subject.java:415）
在org.apache.hadoop.security.UserGroupInformation.doAs（UserGroupInformation.java:1628）
在org.apache.hadoop.mapred.YarnChild .main（YarnChild.java:158）
导致：java.lang.ClassNotFoundException：类未找到
在org.apache.hadoop.conf.Configuration.getClassByName（Configuration.java:1982）
 at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigSplit.readFields（PigSplit.java:224）
 ... 10 more 
 
 Pig Stack Trace 
 --------------- 
错误0：java.io.IOException：java.lang.ClassNotFoundException：未找到类
 
 org.apache。 pig.backend.executionengine.ExecException：错误0：java.io.IOException：java.lang.ClassNotFoundException：未找到类
在org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.MapReduceLauncher.getStats（MapReduceLauncher .java：819）
 at org.apache.pig.backend.hadoop.executionengine.mapReduceLa yer.MapReduceLauncher.launchPig（MapReduceLauncher.java:452）
 at org.apache.pig.backend.hadoop.executionengine.HExecutionEngine.launchPig（HExecutionEngine.java:280）
 at org.apache.pig。 PigServer.launchPlan（PigServer.java:1390）
 at org.apache.pig.PigServer.executeCompiledLogicalPlan（PigServer.java:1375）
 at org.apache.pig.PigServer.execute（PigServer.java： 1364）
在org.apache.pig.PigServer.executeBatch（PigServer.java:415）
在org.apache.pig.PigServer.executeBatch（PigServer.java:398）
在org .apache.pig.tools.grunt.GruntParser.executeBatch（GruntParser.java:171）
在org.apache.pig.tools.grunt.GruntParser.parseStopOnError（GruntParser.java:234）
。在组织.apache.pig.tools.grunt.GruntParser.parseStopOnError（GruntParser.java:205）
在org.apache.pig.tools.grunt.Grunt.exec（Grunt.java:81）
。在组织.apache.pig.Main.run（Main.java:624）
 at org.apache.pig.Main.main（M ain.java:170）在sun.reflect.NativeMethodAccessorImpl.invoke0 
（本机方法）
处sun.reflect sun.reflect.NativeMethodAccessorImpl.invoke（NativeMethodAccessorImpl.java:57）
。 DelegatingMethodAccessorImpl.invoke（DelegatingMethodAccessorImpl.java:43）
 at java.lang.reflect.Method.invoke（Method.java:606）
 at org.apache.hadoop.util.RunJar.run（RunJar。 java：221）
 at org.apache.hadoop.util.RunJar.main（RunJar.java:136）
导致：java.io.IOException：java.lang.ClassNotFoundException：未找到类
 at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigSplit.readFields（PigSplit.java:236）
 at org.apache.hadoop.io.serializer.WritableSerialization $ WritableDeserializer.deserialize（WritableSerialization .java：71）
 at org.apache.hadoop.io.serializer.WritableSerialization $ WritableDeserializer.deserialize（WritableSerialization.java:42）
 at org.apache.hadoop.mapred.M apTask.getSplitDetails（MapTask.java:372）
在org.apache.hadoop.mapred.MapTask.runNewMapper（MapTask.java:751）
在org.apache.hadoop.mapred.MapTask.run（ MapTask.java:341）
 at org.apache.hadoop.mapred.YarnChild $ 2.run（YarnChild.java:163）
 at java.security.AccessController.doPrivileged（Native Method）
在javax.security.auth.Subject.doAs（Subject.java:415）
在org.apache.hadoop.security.UserGroupInformation.doAs（UserGroupInformation.java:1628）
在org.apache.hadoop抛出java.lang.ClassNotFoundException：.mapred.YarnChild.main（YarnChild.java:158）
。通过致类未发现
。在org.apache.hadoop.conf.Configuration.getClassByName（Configuration.java： 1982）
 at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigSplit.readFields（PigSplit.java:224）
 
 
 

请帮我解释一下如何从这里开始。

解决方案

确保你的UDF jar包含在你的Pig ClASSPATH中。
添加以下环境变量：

export PIG_CLASSPATH = / to / jar / location：$ PIG_HOME / pig-0.15.0-h2.jar：$ PIG_CLASSPATH

I tried adding a UDF in a jar and tried the LOAD. The following is my snippet

register 'target/warcbase-0.1.0-SNAPSHOT-fatjar.jar';

DEFINE WarcLoader org.warcbase.pig.WarcLoader();

warc = LOAD '/raw/' USING WarcLoader AS (url: chararray, date: chararray, mime: chararray, content: bytearray);
STORE warc INTO '/raw/proc/';

I got the following Exception. Unfortunately, it does not tell me which class was not found. The following is the entire stack trace

Backend error message
---------------------
Error: java.io.IOException: java.lang.ClassNotFoundException: Class  not found
        at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigSplit.readFields(PigSplit.java:236)
        at org.apache.hadoop.io.serializer.WritableSerialization$WritableDeserializer.deserialize(WritableSerialization.java:71)
        at org.apache.hadoop.io.serializer.WritableSerialization$WritableDeserializer.deserialize(WritableSerialization.java:42)
        at org.apache.hadoop.mapred.MapTask.getSplitDetails(MapTask.java:372)
        at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:751)
        at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
        at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:163)
        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:1628)
        at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158)
Caused by: java.lang.ClassNotFoundException: Class  not found
        at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:1982)
        at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigSplit.readFields(PigSplit.java:224)
        ... 10 more

Pig Stack Trace
---------------
ERROR 0: java.io.IOException: java.lang.ClassNotFoundException: Class  not found

org.apache.pig.backend.executionengine.ExecException: ERROR 0: java.io.IOException: java.lang.ClassNotFoundException: Class  not found
        at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.MapReduceLauncher.getStats(MapReduceLauncher.java:819)
        at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.MapReduceLauncher.launchPig(MapReduceLauncher.java:452)
        at org.apache.pig.backend.hadoop.executionengine.HExecutionEngine.launchPig(HExecutionEngine.java:280)
        at org.apache.pig.PigServer.launchPlan(PigServer.java:1390)
        at org.apache.pig.PigServer.executeCompiledLogicalPlan(PigServer.java:1375)
        at org.apache.pig.PigServer.execute(PigServer.java:1364)
        at org.apache.pig.PigServer.executeBatch(PigServer.java:415)
        at org.apache.pig.PigServer.executeBatch(PigServer.java:398)
        at org.apache.pig.tools.grunt.GruntParser.executeBatch(GruntParser.java:171)
        at org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:234)
        at org.apache.pig.tools.grunt.GruntParser.parseStopOnError(GruntParser.java:205)
        at org.apache.pig.tools.grunt.Grunt.exec(Grunt.java:81)
        at org.apache.pig.Main.run(Main.java:624)
        at org.apache.pig.Main.main(Main.java:170)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at org.apache.hadoop.util.RunJar.run(RunJar.java:221)
        at org.apache.hadoop.util.RunJar.main(RunJar.java:136)
Caused by: java.io.IOException: java.lang.ClassNotFoundException: Class  not found
        at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigSplit.readFields(PigSplit.java:236)
        at org.apache.hadoop.io.serializer.WritableSerialization$WritableDeserializer.deserialize(WritableSerialization.java:71)
        at org.apache.hadoop.io.serializer.WritableSerialization$WritableDeserializer.deserialize(WritableSerialization.java:42)
        at org.apache.hadoop.mapred.MapTask.getSplitDetails(MapTask.java:372)
        at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:751)
        at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
        at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:163)
        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:1628)
        at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158)
Caused by: java.lang.ClassNotFoundException: Class  not found
        at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:1982)
        at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigSplit.readFields(PigSplit.java:224)

Please help me on how to proceed from here.

解决方案

Make sure that your UDF jar is in your Pig ClASSPATH. Add the following environment variable:

export PIG_CLASSPATH=/to/jar/location:$PIG_HOME/pig-0.15.0-h2.jar:$PIG_CLASSPATH

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