NoClassDefFoundError when trying to define a java UDF

[Benjamin Solwitz]

I am attempting to create a java UDF with H2 1.4.196 to replicate the behavior of TRUNC in Oracle. I think I am pretty close, but I am getting an error with the stack trace cut off and I have no idea how to debug it at this point.

Here's my code:

create alias trunc_udf as $$

java.util.Date trunc(java.util.Date dateToTrunc, String whereToTrunc) throws Exception {

  Calendar cal = Calendar.getInstance();

  if(whereToTrunc.equals("HH")) {

    cal.setTime(dateToTrunc);

    cal.set(Calendar.MINUTE, 0);

    cal.set(Calendar.SECOND, 0);

    cal.set(Calendar.MILLISECOND, 0);

    return cal.getTime();

  } else {

    throw new Exception("this H2 UDF only supports HH, please enhance it");

  }

}

$$;

And here's the error message I get back:

Syntax error in SQL statement "/org/h2/dynamic/TRUNC_UDF.java:5: warning: Can't initialize javac processor due to (most likely) a class loader problem: java.lang.NoClassDefFoundError: com/sun/tools/javac/processing/JavacProcessingEnvironment

public class TRUNC_UDF {

       ^

  at lombok.javac.apt.Processor.init(Processor.java:84)

  at lombok.core.AnnotationProcessor$JavacDescriptor.want(AnnotationProcessor.java:87)

  at lombok.core.AnnotationProcessor.init(AnnotationProcessor.java:141)

  at lombok.launch.AnnotationProcessorHider$AnnotationProcessor.init(AnnotationProcessor.java:53)

  at com.sun.tools.javac.processing.JavacProcessingEnvironment$ProcessorState.<init>(JavacProcessingEnvironment.java:500)

  at com.sun.tools.javac.processing.JavacProcessingEnvironment$DiscoveredProcessors$ProcessorStateIterator.next(JavacProcessingEnvironment.java:597)

  at com.sun.tools.javac.processing.JavacProcessingEnvironment.discoverAndRunProcs(JavacProcessingEnvironment.java:690)

  at com.sun.tools.javac.processing.JavacProcessingEnvironment.access$1800(JavacProcessingEnvironment.java:91)

  at com.sun.tools.javac.processing.JavacProcessingEnvironment$Round.run(JavacProcessingEnvironment.java:1035)

  at com.sun.tools.javac.processing.JavacProcessingEnvironment.doProcessing(JavacProcessingEnvironment.java:1176)

  at com.sun.tools.javac.main.JavaCompiler.processAnnotations(JavaCompiler.java:1170)

  at com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:856)

  at com.sun.tools.javac.main.Main.compile(Main.java:523)

  at com.sun.tools.javac.api.JavacTaskImpl.doCall(JavacTaskImpl.java:129)

  at com.sun.tools.javac.api.JavacTaskImpl.call(JavacTaskImpl.java:138)

  at org.h2.util.SourceCompiler.javaxToolsJavac(SourceCompiler.java:287)

  at org.h2.util.SourceCompiler$1.findClass(SourceCompiler.java:150)

  at java.lang.ClassLoader.loadClass(ClassLoader.java:424)

  at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

  at org.h2.util.SourceCompiler.getClass(SourceCompiler.java:164)

  at org.h2.util.SourceCompiler.getMethod(SourceCompiler.java:178)

  at org.h2.engine.FunctionAlias.loadFromSource(FunctionAlias.java:131)

  at org.h2.engine.FunctionAlias.load(FunctionAlias.java:119)

  at org.h2.engine.FunctionAlias.init(FunctionAlias.java:106)

  at org.h2.engine.FunctionAlias.newInstanceFromSource(FunctionAlias.java:98)

  at org.h2.command.ddl.CreateFunctionAlias.update(CreateFunctionAlias.java:53)

  at org.h2.command.CommandContainer.update(CommandContainer.java:101)

  at org.h2.command.Command.executeUpdate(Command.java:260)

  at org.h2.server.TcpServerThread.process(TcpServerThread.java:354)

  at org.h2.server.TcpServerThread.run(TcpServerThread.java:158)

  at java.lang.Thread.run(Thread.java:748)

  Caused by: java.lang.ClassNotFoundException: com.sun.tools.javac.processing.JavacProcessingEnvironment

  at java.lang.ClassLoader.findClass(ClassLoader.java:530)

  at java.lang.ClassLoader.loadClass(ClassLoader.java:424)

  at lombok.launch.ShadowClassLoader.loadClass(ShadowClassLoader.java:418)

  at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

  ... 31 more

1 warning

"; SQL statement:

create alias trunc_udf as $$

java.util.Date trunc(java.util.Date dateToTrunc, String whereToTrunc) throws Exception {

  Calendar cal = Calendar.getInstance();

  if(whereToTrunc.equals("HH")) {

    cal.setTime(dateToTrunc);

    cal.set(Calendar.MINUTE, 0);

    cal.set(Calendar.SECOND, 0);

    cal.set(Calendar.MILLISECOND, 0);

    return cal.getTime();

  } else {

    throw new Exception("this H2 UDF only supports HH, please enhance it");

  }

}

$$;

 [42000-196]

[Noel Grandin]

that is very weird. you seem to be missing part of the javac compiler in your installation.​

[Benjamin Solwitz]

I tried an example from the h2 docs and got the same error:

CREATE ALIAS NEXT_PRIME AS $$

String nextPrime(String value) {

    return new BigInteger(value).nextProbablePrime().toString();

}

$$;

I am starting H2 with gradle, here is the process:

/usr/lib/jvm/java-8-openjdk-amd64/bin/java -Dfile.encoding=UTF-8 -Duser.country=US -Duser.language=en -Duser.variant -cp <huge classpath> org.h2.tools.Server -web -tcp

[Benjamin Solwitz]

Maybe related to this lombok java 8 issue from 2015?

https://github.com/rzwitserloot/lombok/issues/524

[Noel Grandin]

ah, yes, this does indeed look like a lombok problem, not a javac problem. 

You'll need to ask them why they are hooked into the javac compiler like that.

​

[Benjamin Solwitz]

I guess I can fix this by putting it into a jar on the classpath so H2 doesn't need to compile it?

[Noel Grandin]

yup , that could work too​