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class not found exception while running UDF in impala

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Explorer

Hi,

I am running UDF which has sql query .UDF is running fine in Hive.While running in Impala I am getting the below exception.

 


Prettytable cannot resolve string columns values that have  embedded tabs. Reverting to tab delimited text output
++++java.lang.ClassNotFoundException: org.apache.hive.jdbc.HiveDriver
    at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
    at java.net.FactoryURLClassLoader.loadClass(URLClassLoader.java:789)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:190)
    at GetData.evaluate(GetData.java:53)
    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.impala.hive.executor.UdfExecutor.evaluate(UdfExecutor.java:353)
    at org.apache.impala.hive.executor.UdfExecutor.evaluate(UdfExecutor.java:288)
    at org.apache.impala.service.FeSupport.NativeEvalExprsWithoutRow(Native Method)
    at org.apache.impala.service.FeSupport.EvalExprsWithoutRow(FeSupport.java:172)
    at org.apache.impala.service.FeSupport.EvalExprWithoutRow(FeSupport.java:130)
    at org.apache.impala.analysis.LiteralExpr.create(LiteralExpr.java:178)
    at org.apache.impala.rewrite.FoldConstantsRule.apply(FoldConstantsRule.java:68)
    at org.apache.impala.rewrite.ExprRewriter.applyRuleBottomUp(ExprRewriter.java:85)
    at org.apache.impala.rewrite.ExprRewriter.applyRuleRepeatedly(ExprRewriter.java:71)
    at org.apache.impala.rewrite.ExprRewriter.rewrite(ExprRewriter.java:55)
    at org.apache.impala.analysis.SelectList.rewriteExprs(SelectList.java:97)
    at org.apache.impala.analysis.SelectStmt.rewriteExprs(SelectStmt.java:886)
    at org.apache.impala.analysis.AnalysisContext.analyze(AnalysisContext.java:396)
    at org.apache.impala.analysis.AnalysisContext.analyze(AnalysisContext.java:368)
    at org.apache.impala.service.Frontend.analyzeStmt(Frontend.java:903)
    at org.apache.impala.service.Frontend.createExecRequest(Frontend.java:1052)
    at org.apache.impala.service.JniFrontend.createExecRequest(JniFrontend.java:156)

 

I changed driver to  impala driver and tested but still same error with class not found exception on impala driver is coming.

 

Request your inputs or suggestions.

 

Thank You

1 ACCEPTED SOLUTION

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It looks like it's referencing a Java class "org.apache.hive.jdbc.HiveDriver" that's not available on the Impala JVM's classpath. In Hive I assume that that class is deliberately or accidentally on the classpath of the java tasks spawned for the Hive job. Impala doesn't have that class on it's classpath.

 

It seems pretty weird for a UDF to depend on a use a database driver, so my first thought is to modify the UDF to removed the need for the dependency. Otherwise, generally, if you want to use Java classes from your UDF they would need to be built into the UDF JAR.

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2 REPLIES 2

avatar

It looks like it's referencing a Java class "org.apache.hive.jdbc.HiveDriver" that's not available on the Impala JVM's classpath. In Hive I assume that that class is deliberately or accidentally on the classpath of the java tasks spawned for the Hive job. Impala doesn't have that class on it's classpath.

 

It seems pretty weird for a UDF to depend on a use a database driver, so my first thought is to modify the UDF to removed the need for the dependency. Otherwise, generally, if you want to use Java classes from your UDF they would need to be built into the UDF JAR.

avatar
Explorer

Thank You.It worked.