Call java method from Drools rules - java

I want to create a Drools rule that says that if the CPU usage from the data I gather using a HTTP request is over a specific threshold (e.g. 20%) then call a function that lays on the class Netdata which are also passed to Drools Fusion. So what I have written until now is:
rule "CPU usage over 20% once"
when
$cpu : Netdata(cpuUsagePerc > 0)
from entry-point Netdata
then
System.out.println("CPU usage is now over 20%");
$cpu.setCpuOverCount();
end
But the thing is, that I get this error: java.lang.RuntimeException: wrong class format. If I delete this line $cpu.setCpuOverCount(); the rule executes, and prints CPU usage is now over 20% without any problems.
The method I am trying to call is this one:
public void setCpuOverCount() {
cpuOverCount++;
}
Is there a way to call a method in the first place, and if yes how do I do it? If not, how can I overcome such problems?
I am using Drools version 5.1.1.

It could be due to ECJ version not supporting your Java version as per this answer. You can try manually updating the ECJ version:
<dependency>
<groupId>org.eclipse.jdt.core.compiler</groupId>
<artifactId>ecj</artifactId>
<version>>4.5.1</version> <!-- latest is 4.6.1 -->
</dependency>

Related

Issue while Updating drools version from 7.44.0.Final to 7.64.0.Final

I am currently working on updating drools version from 7.44.0.Final to 7.64.0.Final.
We have some customOperators defined extending BaseEvaluator. I face an issue where a call to fireAllRules() ends up in the following method of EvaluatorWrapper.class file: public void loadHandles(InternalFactHandle[] handles, InternalFactHandle rightHandle) which in turn calls private static InternalFactHandle getFactHandle(Declaration declaration, InternalFactHandle[] handles).
This getFactHandles() throws ArrayIndexOutOfBoundsException. I am expecting 2 entries in handles[] array but it shows just 1 due to which we get the ArrayIndexOutOfBoundsException.
It is suspected that the issue could be due to the following change made in drools version 7.52.0 as detailed out here:
https://docs.jboss.org/drools/release/7.57.0.Final/drools-docs/html_single/index.html#optimize-query-payload
While analyzing further, I updated my drools version to 7.49.0.Final and here it works successfully and the flow does not go to the public void loadHandles(InternalFactHandle[] handles, InternalFactHandle rightHandle) & private static InternalFactHandle getFactHandle(Declaration declaration, InternalFactHandle[] handles) in the EvaluatorWrapper.class file.
Here is the Sample DRL... Problem is with the evaluateRight of the Custom Operation.
import java.util.Date;
...
...
dialect \"mvel\"
rule \"update\"
when
$en : Fact(path == \"Encounter\" )
$a : Fact(path == \"Account\" , (($en.getElement(\"subject\") referenceMatch
this.getElement(\"subject\"))))
then
....
end
Kindly let me know if anyone is aware of or has faced similar issues while updating the drools version.

Issue in addPlugInSingleRowFunction upgrading Esper version from 5.3 to 8.3

In our existing application we are using Esper Version 5.3.
We have added few addPlugInSingleRowFunction() to use it in EPL as below --
final Configuration cepConfiguration = new Configuration();
cepConfiguration.addPlugInSingleRowFunction("toNumber", Double.class.getName(), "parseDouble");
cepConfiguration.addPlugInSingleRowFunction("toBoolean", Boolean.class.getName(), "parseBoolean");
This was working fine in 5.3 version.
Post upgrading to 8.3 above code changed as per Esper documentation --
cepConfiguration.getCompiler().addPlugInSingleRowFunction("toNumber", Double.class.getName(), "parseDouble");
cepConfiguration.getCompiler().addPlugInSingleRowFunction("toBoolean", Boolean.class.getName(), "parseBoolean");
But once the sendEventBean() method is called to send a Event to runtime we are seeing below exception every time.
Surprisingly events are getting matched as per the statements present in runtime even if below exception are coming. Though we are not sure whether some events are not matching or not.
Can someone please help on this?
applog.cls=com.espertech.esper.common.internal.epl.expression.dot.core.ExprDotNodeForgeStaticMethodEval,applog.mthd=staticMethodEvalHandleInvocationException,applog.line=228,applog.msg=Invocation exception when invoking method 'parseDouble' of class 'java.lang.Double' passing parameters [null] for statement 'stmt-0': NullPointerException : null,exc.stack=java.lang.NullPointerException\n\tat sun.misc.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:1838)\n\tat sun.misc.FloatingDecimal.parseDouble(FloatingDecimal.java:110)\n\tat java.lang.Double.parseDouble(Double.java:538)\n\tat generated.StatementAIFactoryProvider_a4bd241445010f45474e4598e34521ca1b2836db_stmt450.m8(StatementAIFactoryProvider_a4bd241445010f45474e4598e34521ca1b2836db_stmt450.java:161)\n\tat generated.StatementAIFactoryProvider_a4bd241445010f45474e4598e34521ca1b2836db_stmt450$2.get(ANONYMOUS.java:148)\n\tat com.espertech.esper.runtime.internal.filtersvcimpl.FilterParamIndexEquals.matchEvent(FilterParamIndexEquals.java:32)\n\tat com.espertech.esper.runtime.internal.filtersvcimpl.FilterHandleSetNode.matchEvent(FilterHandleSetNode.java:100)\n\tat com.espertech.esper.runtime.internal.filtersvcimpl.EventTypeIndex.matchType(EventTypeIndex.java:178)\n\tat com.espertech.esper.runtime.internal.filtersvcimpl.EventTypeIndex.matchEvent(EventTypeIndex.java:124)\n\tat com.espertech.esper.runtime.internal.filtersvcimpl.FilterServiceBase.retryableMatchEvent(FilterServiceBase.java:179)\n\tat com.espertech.esper.runtime.internal.filtersvcimpl.FilterServiceBase.evaluateInternal(FilterServiceBase.java:96)\n\tat com.espertech.esper.runtime.internal.filtersvcimpl.FilterServiceLockCoarse.evaluate(FilterServiceLockCoarse.java:52)\n\tat com.espertech.esper.runtime.internal.kernel.service.EPEventServiceImpl.processMatches(EPEventServiceImpl.java:610)\n\tat com.espertech.esper.runtime.internal.kernel.service.EPEventServiceImpl.processWrappedEvent(EPEventServiceImpl.java:450)\n\tat com.espertech.esper.runtime.internal.kernel.thread.InboundUnitSendEvent.run(InboundUnitSendEvent.java:43)\n\tat java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)\n\tat java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)\n\tat java.lang.Thread.run(Thread.java:748)
You could turn on compiler logging (config.getCompiler().getLogging().setEnableCode(true);) and make sure you have INFO level logging. You can inspect "StatementAIFactoryProvider_a4bd241445010f45474e4598e34521ca1b2836db_stmt450.m8" at line 161 to see what the problem is. Sounds like a null value gets passed to Double.parseDouble. But since I don't have the complete code its hard to say.

java.lang.UnsatisfiedLinkError when writing using crunch MemPipeline

I am using com.cloudera.crunch version: '0.3.0-3-cdh-5.2.1'.
I have a small program that reads some AVROs and filters out invalid data based on some criteria. I am using pipeline.write(PCollection, AvroFileTarget) to write the invalid data output. It works fine in production run.
For unit testing this piece of code, I use MemPipeline instance.
But, it fails while writing the output in that case.
I get error:
java.lang.UnsatisfiedLinkError: org.apache.hadoop.util.NativeCrc32.nativeComputeChunkedSumsByteArray(II[BI[BIILjava/lang/String;JZ)V
at org.apache.hadoop.util.NativeCrc32.nativeComputeChunkedSumsByteArray(Native Method)
at org.apache.hadoop.util.NativeCrc32.calculateChunkedSumsByteArray(NativeCrc32.java:86)
at org.apache.hadoop.util.DataChecksum.calculateChunkedSums(DataChecksum.java:428)
at org.apache.hadoop.fs.FSOutputSummer.writeChecksumChunks(FSOutputSummer.java:197)
at org.apache.hadoop.fs.FSOutputSummer.flushBuffer(FSOutputSummer.java:163)
at org.apache.hadoop.fs.FSOutputSummer.flushBuffer(FSOutputSummer.java:144)
at org.apache.hadoop.fs.FSOutputSummer.write(FSOutputSummer.java:78)
at org.apache.hadoop.fs.FSDataOutputStream$PositionCache.write(FSDataOutputStream.java:50)
at java.io.DataOutputStream.writeBytes(DataOutputStream.java:276)
at com.cloudera.crunch.impl.mem.MemPipeline.write(MemPipeline.java:159)
Any idea what's wrong?
Hadoop environment variable should be configured properly along with hadoop.dll and winutils.exe.
Also pass the JVM argument while executing MR job/application
-Djava.library.path=HADOOP_HOME/lib/native

Run an ABCL code that uses cl-cppre

With reference to my previous question,
Executing a lisp function from Java
I was able to call lisp code from Java using ABCL.
But the problem is, the already existing lisp code uses CL-PPCRE package.
I can not compile the code as it says 'CL-PPCRE not found'.
I have tried different approaches to add that package,
including
1) how does one compile a clisp program which uses cl-ppcre?
2)https://groups.google.com/forum/#!topic/cl-ppcre/juSfOhEDa1k
Doesnot work!
Other thing is, that executing (compile-file aima.asd) works perfectly fine although it does also require cl-pprce
(defpackage #:aima-asd
(:use :cl :asdf))
(in-package :aima-asd)
(defsystem aima
:name "aima"
:version "0.1"
:components ((:file "defpackage")
(:file "main" :depends-on ("defpackage")))
:depends-on (:cl-ppcre))
The final java code is
interpreter.eval("(load \"aima/asdf.lisp\")");
interpreter.eval("(compile-file \"aima/aima.asd\")");
interpreter.eval("(compile-file \"aima/defpackage.lisp\")");
interpreter.eval("(in-package :aima)");
interpreter.eval("(load \"aima/aima.lisp\")");
interpreter.eval("(aima-load 'all)");
The error message is
Error loading C:/Users/Administrator.NUIG-1Z7HN12/workspace/aima/probability/domains/edit-nets.lisp at line 376 (offset 16389)
#<THREAD "main" {3A188AF2}>: Debugger invoked on condition of type READER-ERROR
The package "CL-PPCRE" can't be found.
[1] AIMA(1):
Can anyone help me?
You need to load cl-ppcre before you can use it. You can do that by using (asdf:load-system :aima), provided that you put both aima and cl-ppcre into locations that your ASDF searches.
I used QuickLisp to add cl-ppcre (because nothing else worked for me).
Here is what I did
(load \"~/QuickLisp.lisp\")")
(quicklisp-quickstart:install)
(load "~/quicklisp/setup.lisp")
(ql:quickload :cl-ppcre)
First 2 lines are only a one time things. Once quickLisp is installed you can start from line 3.

No Such method error during transformation to pdf in Java

I have a problem while transforming the xslt to pdf in java, i am following the same process posted in this link
"Java Transformation to PDF".
Error:
`
Caused by: java.lang.NoSuchMethodError: org.apache.xmlgraphics.java2d.GraphicContext.<init>(Lorg/apache/xmlgraphics/java2d/GraphicContext;)V
at org.apache.fop.render.intermediate.IFGraphicContext.<init>(IFGraphicContext.java:50)
at org.apache.fop.render.intermediate.IFGraphicContext.clone(IFGraphicContext.java:56)
at org.apache.fop.render.intermediate.IFRenderer.saveGraphicsState(IFRenderer.java:632)
at org.apache.fop.render.intermediate.IFRenderer.startViewport(IFRenderer.java:885)
at org.apache.fop.render.intermediate.IFRenderer.startVParea(IFRenderer.java:878)
at org.apache.fop.render.AbstractRenderer.renderRegionViewport(AbstractRenderer.java:289)
at org.apache.fop.render.intermediate.IFRenderer.renderRegionViewport(IFRenderer.java:731)
at org.apache.fop.render.AbstractRenderer.renderPageAreas(AbstractRenderer.java:249)
at org.apache.fop.render.AbstractRenderer.renderPage(AbstractRenderer.java:230)
at org.apache.fop.render.intermediate.IFRenderer.renderPage(IFRenderer.java:580)
at org.apache.fop.area.RenderPagesModel.addPage(RenderPagesModel.java:114)
at org.apache.fop.layoutmgr.AbstractPageSequenceLayoutManager.finishPage(AbstractPageSequenceLayoutManager.java:312)
at org.apache.fop.layoutmgr.PageSequenceLayoutManager.finishPage(PageSequenceLayoutManager.java:167)
at org.apache.fop.layoutmgr.PageSequenceLayoutManager.activateLayout(PageSequenceLayoutManager.java:109)
at org.apache.fop.area.AreaTreeHandler.endPageSequence(AreaTreeHandler.java:238)
at org.apache.fop.fo.pagination.PageSequence.endOfNode(PageSequence.java:120)
at org.apache.fop.fo.FOTreeBuilder$MainFOHandler.endElement(FOTreeBuilder.java:349)
at org.apache.fop.fo.FOTreeBuilder.endElement(FOTreeBuilder.java:177)
at net.sf.saxon.event.ContentHandlerProxy.endElement(ContentHandlerProxy.java:391)
at net.sf.saxon.event.ProxyReceiver.endElement(ProxyReceiver.java:174)
at net.sf.saxon.event.NamespaceReducer.endElement(NamespaceReducer.java:213)
at net.sf.saxon.event.ComplexContentOutputter.endElement(ComplexContentOutputter.java:417)
at net.sf.saxon.instruct.ElementCreator.processLeavingTail(ElementCreator.java:301)
at net.sf.saxon.instruct.Block.processLeavingTail(Block.java:409)
at net.sf.saxon.instruct.Instruction.process(Instruction.java:94)
at net.sf.saxon.instruct.ElementCreator.processLeavingTail(ElementCreator.java:298)
at net.sf.saxon.instruct.Template.applyLeavingTail(Template.java:175)
at net.sf.saxon.instruct.ApplyTemplates.applyTemplates(ApplyTemplates.java:343)
at net.sf.saxon.Controller.transformDocument(Controller.java:1736)
at net.sf.saxon.Controller.transform(Controller.java:1560)
at mypackage.v2.business.pdf.XMLtoPDF.convertXMLPDF(XMLtoPDF.java:103)
... 51 more
java.lang.ClassCastException: java.lang.NoSuchMethodError cannot be cast to java.lang.Exception
`
Please let me know what could be the problem.
As described in the documentation
Thrown if an application tries to call a specified method of a class (either static or instance), and that class no longer has a definition of that method.
Here's how this can happen. Imagine you built some code that used a library with a method called foo(). You compiled your project and then later decided to upgrade the library. You do this by overwriting the old jar file with the new one. You don't recompile your code.
But what you didn't know is the new library removed the foo() method. Now if you run your code, it will throw this exception because your compile code calls this method and it's no longer there.
In your specific case, this isn't necessarily your code with the problem. It could be that you have one library that uses another library and the problem is there (for example, Library X uses version 2 of Library Y, but you only have Library Y version 1 in your classpath). If this is happening, you need to make sure the libraries are using the version they expect.
For your specific problem, you need to find the version of the jar that has org.apache.xmlgraphics.java2d.GraphicContext in it and it needs to have a constructor that takes a... list of org/apache/xmlgraphics/java2d/GraphicContext... maybe. I forget what (L...;)V means.

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