rdf4j 构造查询失败

Question

我正在尝试使用以下代码片段对维基数据执行构造查询：

construct = "CONSTRUCT { " +
            "   ?s <http://schema.org/about> ?wikipedia ." +
            "} where { " +
            "   OPTIONAL{ " +
            "      ?wikipedia <http://schema.org/about> ?s ; <http://schema.org/inLanguage> ?language ; <http://schema.org/isPartOf> <https://en.wikipedia.org/> . " +
            "   } "+
            "   ?s ?p1 <http://www.wikidata.org/entity/Q12136> . " +
            "}";
            repo = new SPARQLRepository("https://query.wikidata.org/sparql");
            repositoryConnection = repo.getConnection();
            query = repositoryConnection.prepareGraphQuery(construct);
            rs = query.evaluate();
            while (rs.hasNext()) {
                Statement statement = rs.next();
            }

不幸的是，这会导致解析错误：

WARN org.eclipse.rdf4j.rio.helpers.ParseErrorLogger - [Rio error] IRI included an unencoded space: '32' (7730, -1)
org.eclipse.rdf4j.query.QueryEvaluationException: org.eclipse.rdf4j.query.QueryEvaluationException: org.eclipse.rdf4j.rio.RDFParseException: IRI included an unencoded space: '32' [line 7730]
    at org.eclipse.rdf4j.query.impl.QueueCursor.convert(QueueCursor.java:58)
    at org.eclipse.rdf4j.query.impl.QueueCursor.convert(QueueCursor.java:22)
    at org.eclipse.rdf4j.common.iteration.QueueIteration.checkException(QueueIteration.java:165)
    at org.eclipse.rdf4j.common.iteration.QueueIteration.getNextElement(QueueIteration.java:134)
    at org.eclipse.rdf4j.common.iteration.LookAheadIteration.lookAhead(LookAheadIteration.java:81)
    at org.eclipse.rdf4j.common.iteration.LookAheadIteration.hasNext(LookAheadIteration.java:49)
    at org.eclipse.rdf4j.common.iteration.IterationWrapper.hasNext(IterationWrapper.java:63)
    at eu.qanswer.mapping.mappings.informa.Refactor.main(Refactor.java:227)

据我所知，在维基数据中有一些 uri 编码不正确，即 space 在那里。所以 rdf4j 解析器会报错。有没有办法以不太严格的方式配置解析器？

谢谢 D063520

Answer 1

如您所见，这里的问题是您的查询在服务器端超时。您从 RDF4J 获得的错误消息令人困惑，但原因是服务器端点没有正确传达存在问题：它只是创建了一个 200 HTTP 响应（因此 RDF4J 认为一切正常并开始处理响应主体）。中途服务器突然抛出一个错误到响应体中，然后使得RDF4J解析器抛出这个错误。

rdf4j 构造查询失败

rdf4j construct query fails

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