RdfParseException：意外的字符（代码114）遇到[R(RdfParseExcepti

2019-10-18 18:45发布

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我想下面的查询发送到DBpedia中使用dotNetRDF ： 

PREFIX rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX xsd:  <http://www.w3.org/2001/XMLSchema#>
PREFIX temp: <http://www.example.com/temp/>

CONSTRUCT {
  ?v1 a temp:r.
  ?v1 temp:p0 ?v2.
}
WHERE {
  OPTIONAL {
    {
      {
        SELECT ?v1
        WHERE {
          ?v1 rdfs:comment ?v2.
        }
        LIMIT 10
      }.
      ?v1 rdfs:comment ?v2.
    }.
  }.
}

不过，我得到一个RdfParseException说，一个意外r字被发现（114为的十进制字符代码r

当我使用基于Web的DBpedia中的SPARQL形式进行相同的查询，我回来是什么样子合理的结果。 因此，我觉得没有问题，我的SPARQL查询，或至少没有DBpedia中无法应付。

我试图遵循建议有关类似问题的这个问题，通过启用Options.HttpDebugging和Options.HttpFullDebugging 。 作为接受的答案说明这个问题，这并打印到stderr收到的响应。 这不 ，但是，唤起“不同的错误”; 而不是查询似乎是成功的，但是返回的图是空的（不包含三倍）。

下面是再现问题最小样本： 

using System;
using System.Runtime.ConstrainedExecution;

using VDS.RDF;
using VDS.RDF.Query;
using VDS.RDF.Writing;

namespace DotNetRdfParsingError
{
    class Program
    {
        public static void Main(string[] args)
        {
            var endpoint = new SparqlRemoteEndpoint(new Uri("http://dbpedia.org/sparql"));

            string query =
                "PREFIX rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#>\n" +
                "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>\n" +
                "PREFIX xsd:  <http://www.w3.org/2001/XMLSchema#>\n" +
                "PREFIX temp: <http://www.example.com/temp/>\n" +
                "\n" +
                "CONSTRUCT {\n" +
                "  ?v1 a temp:r.\n" +
                "  ?v1 temp:p0 ?v2.\n" +
                "}\n" +
                "WHERE {\n" +
                "  OPTIONAL {\n" +
                "    {\n" +
                "      {\n" +
                "        SELECT ?v1\n" +
                "        WHERE {\n" +
                "          ?v1 rdfs:comment ?v2.\n" +
                "        }\n" +
                "        LIMIT 10\n" +
                "      }.\n" +
                "      ?v1 rdfs:comment ?v2.\n" +
                "    }.\n" +
                "  }.\n" +
                "}";

            Console.WriteLine("Without HTTP debugging:");
            try {
                var graph = endpoint.QueryWithResultGraph(query);
                PrintGraph(graph);
            }
            catch (Exception ex) {
                Console.WriteLine("EXCEPTION:\n" + ex.ToString());
            }

            Console.WriteLine("With HTTP debugging:");
            try {
                Options.HttpDebugging = true;
                Options.HttpFullDebugging = true;
                var graph = endpoint.QueryWithResultGraph(query);
                PrintGraph(graph);
            }
            catch (Exception ex) {
                Console.WriteLine("EXCEPTION:\n" + ex.ToString());
            }
        }

        private static void PrintGraph(IGraph graph)
        {
            if (graph != null) {
                using (var stringWriter = new System.IO.StringWriter()) {
                    var turtleWriter = new TurtleWriter();
                    turtleWriter.PrettyPrintMode = true;
                    turtleWriter.Save(graph, stringWriter);
                    Console.WriteLine("Graph:\n\n" + stringWriter.ToString() + "\n");
                }
            } else {
                Console.WriteLine("Graph is null.");
            }
        }
    }
}

这将产生以下输出： 

Without HTTP debugging:
EXCEPTION:
VDS.RDF.Parsing.RdfParseException: [Line 1 Column 9] Unexpected Character (Code 114) r was encountered
   bei VDS.RDF.Parsing.Tokens.NTriplesTokeniser.GetNextToken()
   bei VDS.RDF.Parsing.Tokens.BufferedTokenQueue.BufferInternal()
   bei VDS.RDF.Parsing.Tokens.BufferedTokenQueue.InitialiseBuffer(Int32 amount)
   bei VDS.RDF.Parsing.NTriplesParser.Parse(TokenisingParserContext context)
   bei VDS.RDF.Parsing.NTriplesParser.Load(IRdfHandler handler, TextReader input)
   bei VDS.RDF.Parsing.NTriplesParser.Load(IRdfHandler handler, StreamReader input)
   bei VDS.RDF.Query.SparqlRemoteEndpoint.QueryWithResultGraph(IRdfHandler handler, String sparqlQuery)
   bei VDS.RDF.Query.SparqlRemoteEndpoint.QueryWithResultGraph(String sparqlQuery)
   bei DotNetRdfParsingError.Program.Main(String[] args) in c:\Users\uname\Documents\Test\DOTNET\DotNetRdfParsingError\DotNetRdfParsingError\Program.cs:Zeile 43.
With HTTP debugging:
# HTTP DEBUGGING #
HTTP Request to http://dbpedia.org/sparql?query=PREFIX%20rdf%3A%20%20%3Chttp%3A%2F%2Fwww.w3.org%2F1999%2F02%2F22-rdf-syntax-ns%23%3E%0APREFIX%20rdfs%3A%20%3Chttp%3A%2F%2Fwww.w3.org%2F2000%2F01%2Frdf-schema%23%3E%0APREFIX%20xsd%3A%20%20%3Chttp%3A%2F%2Fwww.w3.org%2F2001%2FXMLSchema%23%3E%0APREFIX%20temp%3A%20%3Chttp%3A%2F%2Fwww.example.com%2Ftemp%2F%3E%0A%0ACONSTRUCT%20%7B%0A%20%20%3Fv1%20a%20temp%3Ar.%0A%20%20%3Fv1%20temp%3Ap0%20%3Fv2.%0A%7D%0AWHERE%20%7B%0A%20%20OPTIONAL%20%7B%0A%20%20%20%20%7B%0A%20%20%20%20%20%20%7B%0A%20%20%20%20%20%20%20%20SELECT%20%3Fv1%0A%20%20%20%20%20%20%20%20WHERE%20%7B%0A%20%20%20%20%20%20%20%20%20%20%3Fv1%20rdfs%3Acomment%20%3Fv2.%0A%20%20%20%20%20%20%20%20%7D%0A%20%20%20%20%20%20%20%20LIMIT%2010%0A%20%20%20%20%20%20%7D.%0A%20%20%20%20%20%20%3Fv1%20rdfs%3Acomment%20%3Fv2.%0A%20%20%20%20%7D.%0A%20%20%7D.%0A%7D

GET
Accept:text/plain,text/ntriples,text/ntriples+turtle,application/rdf-triples,application/x-ntriples,text/plain,text/ntriples,text/ntriples+turtle,application/rdf-triples,application/x-ntriples,text/turtle,application/x-turtle,application/turtle,text/turtle,application/x-turtle,application/turtle,text/n3,text/rdf+n3,text/n3,text/rdf+n3,application/rdf+xml,text/xml,application/xml,application/rdf+xml,text/xml,application/xml,application/json,text/json,application/rdf+json,application/json,text/json,application/rdf+json,text/html,application/xhtml+xml,text/html,application/xhtml+xml,*/*;q=0.5


HTTP Response from http://dbpedia.org/sparql?query=PREFIX%20rdf%3A%20%20%3Chttp%3A%2F%2Fwww.w3.org%2F1999%2F02%2F22-rdf-syntax-ns%23%3E%0APREFIX%20rdfs%3A%20%3Chttp%3A%2F%2Fwww.w3.org%2F2000%2F01%2Frdf-schema%23%3E%0APREFIX%20xsd%3A%20%20%3Chttp%3A%2F%2Fwww.w3.org%2F2001%2FXMLSchema%23%3E%0APREFIX%20temp%3A%20%3Chttp%3A%2F%2Fwww.example.com%2Ftemp%2F%3E%0A%0ACONSTRUCT%20%7B%0A%20%20%3Fv1%20a%20temp%3Ar.%0A%20%20%3Fv1%20temp%3Ap0%20%3Fv2.%0A%7D%0AWHERE%20%7B%0A%20%20OPTIONAL%20%7B%0A%20%20%20%20%7B%0A%20%20%20%20%20%20%7B%0A%20%20%20%20%20%20%20%20SELECT%20%3Fv1%0A%20%20%20%20%20%20%20%20WHERE%20%7B%0A%20%20%20%20%20%20%20%20%20%20%3Fv1%20rdfs%3Acomment%20%3Fv2.%0A%20%20%20%20%20%20%20%20%7D%0A%20%20%20%20%20%20%20%20LIMIT%2010%0A%20%20%20%20%20%20%7D.%0A%20%20%20%20%20%20%3Fv1%20rdfs%3Acomment%20%3Fv2.%0A%20%20%20%20%7D.%0A%20%20%7D.%0A%7D
HTTP/1.1 200 OK

Connection:keep-alive
Vary:Accept-Encoding
Accept-Ranges:bytes
Content-Length:5451
Content-Type:text/plain
Date:Fri, 18 Oct 2013 08:06:33 GMT
Server:Virtuoso/07.00.3204 (Linux) i686-generic-linux-glibc212-64  VDB

@prefix rdf:    <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix ns1:    <http://www.example.com/temp/> .
<http://dbpedia.org/resource/American_Legion_Field_(Florence)>  rdf:type    ns1:r ;
    ns1:p0  "American Legion Field is a baseball venue in Florence, South Carolina, USA. It is home to the Florence Red Wolves of the Coastal Plain League, a collegiate summer baseball league. The Red Wolves have played at the field since 1998. The venue was built sometime before 1981 and has a capacity of 3,500. The field's dimensions are 305 ft. down the foul lines, 335 ft. to the gaps, and 385 ft. to dead center field."@en .
@prefix dbpedia:    <http://dbpedia.org/resource/> .
dbpedia:Francisco_Bautista  rdf:type    ns1:r ;
    ns1:p0  "Francisco Bautista Cuamatzi is a male long-distance runner from Mexico. He represented his native country at the 2008 Summer Olympics in Beijing, PR China, where he finished in 66th place in the men's marathon event, clocking 2:29.28. Rojas set his personal best in the marathon on March 7, 2004 in Torre\u00F3n."@en ,
        "Francisco Bautista ist ein mexikanischer Marathonl\u00E4ufer. Bei den Halbmarathon-Weltmeisterschaften 1999 in Palermo kam er auf den 87. Platz. Im Jahr darauf wurde er F\u00FCnfter beim Marat\u00F3n de la Comarca Lagunera und Achter beim Mailand-Marathon. 2001 wurde er Sechster in der Comarca Lagunera, Zentralamerika/Karibik-Vizemeister im Halbmarathon, belegte bei den Leichtathletik-Weltmeisterschaften in Edmonton Rang 66 und gewann den Monterrey-Marathon."@de .
<http://dbpedia.org/resource/Tillandsia_\u0027Comet\u0027>  rdf:type    ns1:r ;
    ns1:p0  "'Comet' is a hybrid cultivar of the genus Tillandsia in the Bromeliad family."@en .
dbpedia:Glass_Sky   rdf:type    ns1:r ;
    ns1:p0  "Glass Sky is a Japanese manga anthology written and illustrated by Yugi Yamada. It is licensed in North America by Digital Manga Publishing, which released the manga through its June imprint, on December 12, 2007."@en .
dbpedia:Healthcare_in_Guntur    rdf:type    ns1:r ;
    ns1:p0  "The region of Guntur has many health care facilities supported by both the government and private institutions. It is one of the major cities on the east coast region of India in providing excellent medical and health care facilities."@en .
dbpedia:Lake_Nuijamaa   rdf:type    ns1:r ;
    ns1:p0  "Lake Nuijamaa is a lake on the border between Finland and Russia next to the town of Nuijamaa. It is part of the Saimaa Canal linking Vyborg Bay in the Baltic Sea to Lake Saimaa in the Finnish Lakeland."@en ,
        "\u041D\u0443\u0439\u044F\u043C\u0430\u044F\u0440\u0432\u0438\u00A0\u2014 \u043E\u0437\u0435\u0440\u043E \u043D\u0430 \u041A\u0430\u0440\u0435\u043B\u044C\u0441\u043A\u043E\u043C \u043F\u0435\u0440\u0435\u0448\u0435\u0439\u043A\u0435 \u043D\u0430 \u0433\u0440\u0430\u043D\u0438\u0446\u0435 \u0424\u0438\u043D\u043B\u044F\u043D\u0434\u0438\u0438 \u0438 \u0420\u043E\u0441\u0441\u0438\u0438. \u041E\u0437\u0435\u0440\u043E \u0440\u0430\u0441\u043F\u043E\u043B\u043E\u0436\u0435\u043D\u043E \u0432 20 \u043A\u043C \u043D\u0430 \u044E\u0433\u043E-\u0432\u043E\u0441\u0442\u043E\u043A \u043E\u0442 \u0444\u0438\u043D\u0441\u043A\u043E\u0433\u043E \u0433\u043E\u0440\u043E\u0434\u0430 \u041B\u0430\u043F\u043F\u0435\u044D\u043D\u0440\u0430\u043D\u0442\u0430 \u0438 \u0432 26\u00A0\u043A\u043C \u043D\u0430 \u0441\u0435\u0432\u0435\u0440\u043E-\u0437\u0430\u043F\u0430\u0434 \u043E\u0442 \u0440\u043E\u0441\u0441\u0438\u0439\u0441\u043A\u043E\u0433\u043E \u0412\u044B\u0431\u043E\u0440\u0433\u0430. \u0427\u0435\u0440\u0435\u0437 \u043D\u0435\u0433\u043E \u043F\u0440\u043E\u0445\u043E\u0434\u0438\u0442 \u0421\u0430\u0439\u043C\u0435\u043D\u0441\u043A\u0438\u0439 \u043A\u0430\u043D\u0430\u043B."@ru .
dbpedia:Michelangelo_Unterberger    rdf:type    ns1:r ;
    ns1:p0  "Michelangelo Unterberger (August 11, 1695 \u2013 June 27, 1758), was an Austrian painter. Unterberger was born at Cavalese, in what was then Austrian Tyrol, and was part of an Austrian family of artists. He was originally taught by Giuseppe Alberti, and painted primarily religious-themed works."@en ,
        "Michelangelo Unterberger, auch Michael Angelo Unterberger und Michelangelo Unterperger war ein S\u00FCdtiroler Maler des Barock."@de ,
        "Michelangelo Unterberger, aussi Michael Angelo Unterberger ou Michelangelo Unterperger est un peintre autrichien, originaire de la province autonome de Bolzano, et de l'\u00E9poque baroque."@fr .
<http://dbpedia.org/resource/Miroslav_Ivani%C5%A1evi%C4%87> rdf:type    ns1:r ;
    ns1:p0  "Miroslav Ivani\u0161evi\u0107 is a Montenegrin politician. He was appointed as the Montenegrin Minister of Finance in 1998. In 2007 he was accused of being involved in cigarette smuggling into Italy, but was found not guilty in 2010."@en .
dbpedia:Skin_for_Skin   rdf:type    ns1:r ;
    ns1:p0  "Skin for Skin \u00E8 per ora l'ultimo album pubblicato dalla heavy/christian metal band Bride, nel 2006."@it ,
        "Skin for Skin \u00E9 um \u00E1lbum da banda de heavy metal Bride, lan\u00E7ado em 2006 pela gravadora Retrospective Records. A banda sai de seu estilo alternativo e lan\u00E7a um [disco extremamente pesado e totalmente heavy metal.]"@pt ,
        "Skin for Skinis the twelfth studio album by the rock band Bride."@en .
<http://dbpedia.org/resource/Union_Church_(Buckfield,_Maine)>   rdf:type    ns1:r ;
    ns1:p0  "Union Church is a historic church off ME 140 in Buckfield, Maine. It was built in 1832 and added to the National Register of Historic Places in 1980."@en .

# END HTTP DEBUGGING #
Graph:

@base <http://dbpedia.org/sparql>.

@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>.
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#>.
@prefix xsd: <http://www.w3.org/2001/XMLSchema#>.

如那里可以看出，所得到的曲线图只包括一些前缀的，但不包含任何节点或三元组。

该异常点线1，第9栏，将得到的曲线图，其中-在寻找所接收的响应的情况下，将是开始时rdf前缀声明的前缀

@prefix rdf:    <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .

有一件事我觉得奇怪的是，异常被抛出NTriplesTokeniser某处里面NTriplesParser ，但返回的图在我看来像乌龟而不是的N-Triples 。

我使用的是最新版本的dotNetRDF从的NuGet ，目前1.0.1.2809。

我在做什么不对劲的地方，还是有在这种情况下，需要dotNetRDF任何额外的设置吗？

编辑：为了完整起见，我要补充的是在本地安装的Virtuoso里面一些DBpedia的数据，也没有崩溃。

Answer 1:

是的，它看起来像DBpedia中是做了错误的事情，由于某种原因，返回龟与Content-Type的text/plain而不是甲鱼这将是适当的值， application/turtle 。 因此，为什么dotNetRDF选择NTriples分析器，然后运行到的问题。

这将是值得这个报告向DBpedia的乡亲看看他们是否能解决这个问题

dotNetRDF可以提高我们如何形成我们Accept头把text/plain在列表中向下低，但这仍然不能解决DBpedia中似乎不正确地做内容协商的事实。

您可以使用RdfAcceptHeader属性来解决这里面的文件说：

可以用要解决车终点不一样的宽广Accept标头dotNetRDF默认发送。

例如： 

endpoint.RdfAcceptHeader = "application/turtle";

有了这个解决办法在地方给出的代码不会抛出异常。

除了HTTP调试

最后一边关于HTTP调试唤起一个不同的错误的点， Options.HttpFullDebugging所以解析器接收流，其已经在端部消耗的响应流。

根据不同的解析器，这可能会导致不同的解析错误，但在NTriples的情况下，这是一个文本格式的空流是一个有效的空图形序列。 该图恰好有一些前缀，因为Graph中dotNetRDF情况下，总是有前缀rdf ， rdfs和xsd默认定义。



文章来源: RdfParseException: Unexpected Character (Code 114) r was encountered
标签： rdf sparql dbpedia dotnetrdf
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