Fix coming shortly but the work around is...
change:
Expr x = new NodeValueInteger(1)
to:
NodeValue nv = new NodeValueInteger(1)
nv.asNode()
Expr x = nv;
Claude
On Sat, Nov 18, 2017 at 3:48 PM, Claude Warren <cla...@xenei.com> wrote:
> Well done Andy. Right on the money, exactly what I discovered.
>
> On Sat, Nov 18, 2017 at 3:39 PM, Andy Seaborne <a...@apache.org> wrote:
>
>> c.f. NodeValue.getNode and NodeValue.asNode
>>
>> Presumably something calls getNode when it wanted asNode.
>>
>>
>> On 18/11/17 15:36, Claude Warren wrote:
>>
>>> This is a bug. The problem is that new NodeValueInteger(1);
>>> does not set the Node value that the rewriter is trying to rewrite and
>>> thus
>>> the null pointer exception.
>>>
>>> I will get a fix out shortly.
>>>
>>> Claude
>>>
>>> On Fri, Nov 17, 2017 at 4:14 PM, Chris Dollin <
>>> chris.dol...@epimorphics.com>
>>> wrote:
>>>
>>> Hi,
>>>>
>>>> I was experimenting with the query builder and hit a problem
>>>> when I was attempting to construct an Expr. This example:
>>>>
>>>> package com.epimorphics.scratch;
>>>>
>>>> import org.apache.jena.arq.querybuilder.ConstructBuilder;
>>>> import org.apache.jena.sparql.expr.E_GreaterThan;
>>>> import org.apache.jena.sparql.expr.Expr;
>>>> import org.apache.jena.sparql.expr.ExprVar;
>>>> import org.apache.jena.sparql.expr.nodevalue.NodeValueInteger;
>>>> import org.junit.Test;
>>>>
>>>> public class Example {
>>>>
>>>> @Test public void tryBuilding() {
>>>> ConstructBuilder cb = new ConstructBuilder();
>>>>
>>>> Expr x = new NodeValueInteger(1);
>>>> Expr y = new ExprVar("y");
>>>> Expr e = new E_GreaterThan(x, y);
>>>> cb.addFilter(e);
>>>> System.err.println(cb.buildString());
>>>> }
>>>> }
>>>>
>>>> when run fails with a null pointer exception:
>>>>
>>>> java.lang.NullPointerException
>>>> at org.apache.jena.arq.querybuilder.rewriters.
>>>> AbstractRewriter.changeNode(AbstractRewriter.java:126)
>>>> at org.apache.jena.arq.querybuilder.rewriters.NodeValueRewriter
>>>> .visit(
>>>> NodeValueRewriter.java:64)
>>>> at org.apache.jena.sparql.expr.nodevalue.NodeValueInteger.
>>>> visit(NodeValueInteger.java:78)
>>>> at org.apache.jena.arq.querybuilder.rewriters.ExprRewriter.visit(
>>>> ExprRewriter.java:127)
>>>> at org.apache.jena.sparql.expr.NodeValue.visit(NodeValue.java:1
>>>> 205)
>>>> at org.apache.jena.arq.querybuilder.rewriters.ExprRewriter.visit(
>>>> ExprRewriter.java:65)
>>>> at org.apache.jena.sparql.expr.ExprFunction2.visit(
>>>> ExprFunction2.java:109)
>>>> at org.apache.jena.arq.querybuilder.rewriters.ElementRewriter.v
>>>> isit(
>>>> ElementRewriter.java:70)
>>>> at org.apache.jena.sparql.syntax.ElementFilter.visit(
>>>> ElementFilter.java:35)
>>>> at org.apache.jena.arq.querybuilder.rewriters.ElementRewriter.v
>>>> isit(
>>>> ElementRewriter.java:141)
>>>> at org.apache.jena.sparql.syntax.ElementGroup.visit(
>>>> ElementGroup.java:120)
>>>> at org.apache.jena.arq.querybuilder.handlers.WhereHandler.addAll(
>>>> WhereHandler.java:81)
>>>> at org.apache.jena.arq.querybuilder.handlers.HandlerBlock.addAll(
>>>> HandlerBlock.java:218)
>>>> at org.apache.jena.arq.querybuilder.handlers.HandlerBlock.addAll(
>>>> HandlerBlock.java:245)
>>>> at org.apache.jena.arq.querybuilder.AbstractQueryBuilder.build(
>>>> AbstractQueryBuilder.java:555)
>>>> at org.apache.jena.arq.querybuilder.AbstractQueryBuilder.buildS
>>>> tring(
>>>> AbstractQueryBuilder.java:522)
>>>> at com.epimorphics.scratch.Example.tryBuilding(Example.java:20)
>>>> at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
>>>> at sun.reflect.NativeMethodAccessorImpl.invoke(
>>>> NativeMethodAccessorImpl.java:62)
>>>> at sun.reflect.DelegatingMethodAccessorImpl.invoke(
>>>> DelegatingMethodAccessorImpl.java:43)
>>>> at java.lang.reflect.Method.invoke(Method.java:498)
>>>> at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(
>>>> FrameworkMethod.java:47)
>>>> at org.junit.internal.runners.model.ReflectiveCallable.run(
>>>> ReflectiveCallable.java:12)
>>>> at org.junit.runners.model.FrameworkMethod.invokeExplosively(
>>>> FrameworkMethod.java:44)
>>>> at org.junit.internal.runners.statements.InvokeMethod.
>>>> evaluate(InvokeMethod.java:17)
>>>> at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
>>>> at org.junit.runners.BlockJUnit4ClassRunner.runChild(
>>>> BlockJUnit4ClassRunner.java:70)
>>>> at org.junit.runners.BlockJUnit4ClassRunner.runChild(
>>>> BlockJUnit4ClassRunner.java:50)
>>>> at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
>>>> at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
>>>> at org.junit.runners.ParentRunner.runChildren(ParentRunner.java
>>>> :236)
>>>> at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
>>>> at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:
>>>> 229)
>>>> at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
>>>> at org.junit.runner.JUnitCore.run(JUnitCore.java:160)
>>>> at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(
>>>> JUnit4IdeaTestRunner.java:68)
>>>> at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.
>>>> startRunnerWithArgs(IdeaTestRunner.java:47)
>>>> at com.intellij.rt.execution.junit.JUnitStarter.
>>>> prepareStreamsAndStart(
>>>> JUnitStarter.java:242)
>>>> at com.intellij.rt.execution.junit.JUnitStarter.main(
>>>> JUnitStarter.java:70)
>>>>
>>>> Replacing the addFilter line with
>>>>
>>>> cb.addFilter("1 > ?y");
>>>>
>>>> does not fail, terminating with the expected print-out
>>>> of a construct query
>>>>
>>>> CONSTRUCT
>>>> {
>>>> }
>>>> WHERE
>>>> { FILTER ( 1 > ?y )}
>>>>
>>>> I tried poking around with the debugger but couldn't see anyhting
>>>> obvious. However, /sometimes/ stepping through the code
>>>> results in it working and sometimes not, presumably depending
>>>> on exactly when I give up through-stepping.
>>>>
>>>> Am I doing anything obviously wrong (like misunderstanding
>>>> how to use the Expr functionality) or should I file a JIRA?
>>>> This is Jena 3.4.0.
>>>>
>>>> Chris
>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> "What I don't understand is this ..." Trevor Chaplin, /The Beiderbeck
>>>> Affair/
>>>>
>>>> Epimorphics Ltd, http://www.epimorphics.com
>>>> Registered address: Court Lodge, 105 High Street, Portishead, Bristol
>>>> BS20
>>>> 6PT
>>>> Epimorphics Ltd. is a limited company registered in England (number
>>>> 7016688)
>>>>
>>>>
>>>
>>>
>>>
>
>
> --
> I like: Like Like - The likeliest place on the web
> <http://like-like.xenei.com>
> LinkedIn: http://www.linkedin.com/in/claudewarren
>
--
I like: Like Like - The likeliest place on the web
<http://like-like.xenei.com>
LinkedIn: http://www.linkedin.com/in/claudewarren
