This code can be used to see the HttpException (500 Server Error) remotely
(only 18 results found before the exception occurs):
import com.hp.hpl.jena.query.QueryExecution;
import com.hp.hpl.jena.query.QueryExecutionFactory;
import com.hp.hpl.jena.query.QueryFactory;
import com.hp.hpl.jena.query.QuerySolution;
import com.hp.hpl.jena.query.ResultSet;
import com.hp.hpl.jena.rdf.model.ModelFactory;
import com.hp.hpl.jena.sparql.core.DatasetImpl;
public class Query {
public static void main(String[] args) {
String query = "PREFIX owl: <http://www.w3.org/2002/07/owl#>\n"
+
"PREFIX geopos: <
http://www.w3.org/2003/01/geo/wgs84_pos#>\n" +
"select ?s ?lat ?long where {\n" +
" SERVICE
<http://*fuseki.mooo.com:8080*/lgd-dbpedia/sparql>
{\n" +
" select * where {\n" +
" ?s owl:sameAs ?geo .\n" +
" FILTER regex(str(?geo),\"dbpedia\")\n"
+
" } \n" +
" }\n" +
" SERVICE
<http://*fuseki.mooo.com:8080*/dbpedia-geo/sparql>
{\n" +
" select * where{\n" +
" ?geo geopos:lat ?lat ;\n" +
" geopos:long ?long .\n" +
" } \n" +
" } \n" +
"} \n";
long start = System.currentTimeMillis();
QueryExecution exec =
QueryExecutionFactory.create(QueryFactory.create(query),
new
DatasetImpl(ModelFactory.createDefaultModel()));
ResultSet rs = exec.execSelect();
int n = 0;
while (rs.hasNext()) {
rs.next();
System.out.print(++n + " ");
}
long time = System.currentTimeMillis() - start;
System.out.println(n + " results found in " + time + "ms.");
}
}
Abraços,
Regis.
2012/4/8 Regis Pires Magalhães <[email protected]>
> Andy,
> The exception is always the same NoRouteToHostException and we the only
> proxy we use between the client and the Fuseki server is a reverse proxy
> (NginX).
>
> I've also observed that the number of network connections with the server
> increases from 0 to a bit more than 28000, when the exception
> occurs. Almost all of the connections are TIME_WAIT.
>
> When I try a direct connection to Fuseki (even locally using 127.0.0.1 as
> the address to the Sparql Endpoint) I only get 17 results (the number of
> connections increases from 0 to 212) and the exception changes to:
>
> Exception in thread "main" HttpException: HttpException: 500 Server Error
> : HttpException: 500 Server Error
> at
> com.hp.hpl.jena.sparql.engine.http.HttpQuery.execCommon(HttpQuery.java:375)
> at com.hp.hpl.jena.sparql.engine.http.HttpQuery.execGet(HttpQuery.java:202)
> at com.hp.hpl.jena.sparql.engine.http.HttpQuery.exec(HttpQuery.java:157)
> at com.hp.hpl.jena.sparql.engine.http.Service.exec(Service.java:71)
> at
> com.hp.hpl.jena.sparql.engine.main.iterator.QueryIterService.nextStage(QueryIterService.java:53)
> at
> com.hp.hpl.jena.sparql.engine.iterator.QueryIterRepeatApply.makeNextStage(QueryIterRepeatApply.java:113)
> at
> com.hp.hpl.jena.sparql.engine.iterator.QueryIterRepeatApply.hasNextBinding(QueryIterRepeatApply.java:65)
> at
> com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:108)
> at
> com.hp.hpl.jena.sparql.engine.iterator.QueryIterConvert.hasNextBinding(QueryIterConvert.java:65)
> at
> com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:108)
> at
> com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorWrapper.hasNextBinding(QueryIteratorWrapper.java:40)
> at
> com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:108)
> at
> com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorWrapper.hasNextBinding(QueryIteratorWrapper.java:40)
> at
> com.hp.hpl.jena.sparql.engine.iterator.QueryIteratorBase.hasNext(QueryIteratorBase.java:108)
> at
> com.hp.hpl.jena.sparql.engine.ResultSetStream.hasNext(ResultSetStream.java:72)
> at Query.main(Query.java:42)
> Caused by: HttpException: 500 Server Error
> at
> com.hp.hpl.jena.sparql.engine.http.HttpQuery.execCommon(HttpQuery.java:320)
> ... 15 more
>
> How could I get all the results?
>
> Regards,
> Regis.
>
>
>
> On Sun, Apr 8, 2012 at 7:38 AM, Andy Seaborne <[email protected]> wrote:
>
>> On 08/04/12 01:30, Regis Pires Magalhăes wrote:
>>
>>> I've got a sucessful result when executing *outside* our intranet (LAN).
>>>
>>> All the 43016 results were returned.
>>> It seems that there are so many requests (when executing in the Local
>>> Network) that the server or the client can not properly
>>> handle them. Suggestions? I could not receive more than 5000 results when
>>> querying inside the LAN. Results come much faster, but the exception
>>> always
>>> occurs.
>>>
>>> Regis.
>>>
>>
>> Is it the same exception? NoRouteToHostException isn't usually a sign of
>> overload - it's a sign that the JVM inside the firewall can't contact the
>> machine outside. Your proxy may be doing funny stuff though.
>>
>> Do you have proxy settings given to the JVM?it should work.
>>
>> -Dhttp.proxyHost=...
>> -Dhttp.proxyPort=...
>>
>> or
>> -DsocksProxyHost=...
>> -DsocksProxyPort=...
>>
>> Andy
>>
>>
>>>
>>> 2012/4/7 Regis Pires
>>> Magalhăes<regispiresmag@gmail.**com<[email protected]>
>>> >
>>>
>>>
>>>> I get a "java.net.**NoRouteToHostException: Cannot assign requested
>>>> address"
>>>> exception when I execute que following code:
>>>>
>>>> import com.hp.hpl.jena.query.**QueryExecution;
>>>> import com.hp.hpl.jena.query.**QueryExecutionFactory;
>>>> import com.hp.hpl.jena.query.**QueryFactory;
>>>> import com.hp.hpl.jena.query.**QuerySolution;
>>>> import com.hp.hpl.jena.query.**ResultSet;
>>>> import com.hp.hpl.jena.rdf.model.**ModelFactory;
>>>> import com.hp.hpl.jena.sparql.core.**DatasetImpl;
>>>>
>>>> public class Query {
>>>> public static void main(String[] args) {
>>>> String query = "PREFIX owl:<
>>>> http://www.w3.org/2002/07/owl#**>\n" +
>>>> "PREFIX geopos:<
>>>> http://www.w3.org/2003/01/geo/**wgs84_pos#<http://www.w3.org/2003/01/geo/wgs84_pos#>>\n"
>>>> +
>>>> "select ?s ?lat ?long where {\n" +
>>>> " SERVICE<
>>>> http://fuseki.mooo.com/lgd-**dbpedia/sparql<http://fuseki.mooo.com/lgd-dbpedia/sparql>>
>>>> {\n" +
>>>> " select * where {\n" +
>>>> " ?s owl:sameAs ?geo .\n" +
>>>> " FILTER
>>>> regex(str(?geo),\"dbpedia\")\**n" +
>>>> " } \n" +
>>>> " }\n" +
>>>> " SERVICE<
>>>> http://fuseki.mooo.com/**dbpedia-geo/sparql<http://fuseki.mooo.com/dbpedia-geo/sparql>>
>>>> {\n" +
>>>> " select * where{\n" +
>>>> " ?geo geopos:lat ?lat ;\n" +
>>>> " geopos:long ?long .\n" +
>>>> " } \n" +
>>>> " } \n" +
>>>> "} \n";
>>>>
>>>> long start = System.currentTimeMillis();
>>>> QueryExecution exec =
>>>> QueryExecutionFactory.create(**QueryFactory.create(query),
>>>> new
>>>> DatasetImpl(ModelFactory.**createDefaultModel()));
>>>> ResultSet rs = exec.execSelect();
>>>> int n = 0;
>>>> while (rs.hasNext()) {
>>>> rs.next();
>>>> System.out.print(++n + " ");
>>>> }
>>>> long time = System.currentTimeMillis() - start;
>>>> System.out.println(n + " results found in " + time +
>>>> "ms.");
>>>> }
>>>> }
>>>>
>>>> The same query runs perfectly when a do limit in the first SERVICE
>>>> select:
>>>>
>>>> String query = "PREFIX owl:<
>>>> http://www.w3.org/2002/07/owl#**>\n" +
>>>> "PREFIX geopos:<
>>>> http://www.w3.org/2003/01/geo/**wgs84_pos#<http://www.w3.org/2003/01/geo/wgs84_pos#>>\n"
>>>> +
>>>> "select ?s ?lat ?long where {\n" +
>>>> " SERVICE<
>>>> http://fuseki.mooo.com/lgd-**dbpedia/sparql<http://fuseki.mooo.com/lgd-dbpedia/sparql>>
>>>> {\n" +
>>>> " select * where {\n" +
>>>> " ?s owl:sameAs ?geo .\n" +
>>>> " FILTER
>>>> regex(str(?geo),\"dbpedia\")\**n" +
>>>> " } *limit 20000* \n" +
>>>>
>>>> " }\n" +
>>>> " service<
>>>> http://fuseki.mooo.com/**dbpedia-geo/sparql<http://fuseki.mooo.com/dbpedia-geo/sparql>>
>>>> {\n" +
>>>> " select * where{\n" +
>>>> " ?geo geopos:lat ?lat ;\n" +
>>>> " geopos:long ?long .\n" +
>>>> " } \n" +
>>>> " } \n" +
>>>> "} \n";
>>>>
>>>>
>>>> What can I do to fix the problem? It always occurs when the query is
>>>> run,
>>>> even when the Fuseki Sparql Endpoint is running locally.
>>>> I did not observe any problem related to the network. The problem
>>>> persists
>>>> when the code (query) is executed in different hosts.
>>>> I am using Jena classes from "fuseki-server.jar" in the client
>>>> classpath.
>>>> I've also tested different Fuseki jar versions: 0.2.1, 0.2.2.
>>>> The full stack trace is this:
>>>>
>>>> Exception in thread "main" HttpException:
>>>> java.net.**NoRouteToHostException: Cannot assign requested address:
>>>> java.net.**NoRouteToHostException: Cannot assign requested address
>>>> at
>>>> com.hp.hpl.jena.sparql.engine.**http.HttpQuery.execGet(**
>>>> HttpQuery.java:216)
>>>> at com.hp.hpl.jena.sparql.engine.**http.HttpQuery.exec(HttpQuery.**
>>>> java:157)
>>>> at com.hp.hpl.jena.sparql.engine.**http.Service.exec(Service.**
>>>> java:71)
>>>> at
>>>> com.hp.hpl.jena.sparql.engine.**main.iterator.**
>>>> QueryIterService.nextStage(**QueryIterService.java:53)
>>>> at
>>>> com.hp.hpl.jena.sparql.engine.**iterator.QueryIterRepeatApply.**
>>>> makeNextStage(**QueryIterRepeatApply.java:113)
>>>> at
>>>> com.hp.hpl.jena.sparql.engine.**iterator.QueryIterRepeatApply.**
>>>> hasNextBinding(**QueryIterRepeatApply.java:65)
>>>> at
>>>> com.hp.hpl.jena.sparql.engine.**iterator.QueryIteratorBase.**
>>>> hasNext(QueryIteratorBase.**java:108)
>>>> at
>>>> com.hp.hpl.jena.sparql.engine.**iterator.QueryIterConvert.**
>>>> hasNextBinding(**QueryIterConvert.java:65)
>>>> at
>>>> com.hp.hpl.jena.sparql.engine.**iterator.QueryIteratorBase.**
>>>> hasNext(QueryIteratorBase.**java:108)
>>>> at
>>>> com.hp.hpl.jena.sparql.engine.**iterator.QueryIteratorWrapper.**
>>>> hasNextBinding(**QueryIteratorWrapper.java:40)
>>>> at
>>>> com.hp.hpl.jena.sparql.engine.**iterator.QueryIteratorBase.**
>>>> hasNext(QueryIteratorBase.**java:108)
>>>> at
>>>> com.hp.hpl.jena.sparql.engine.**iterator.QueryIteratorWrapper.**
>>>> hasNextBinding(**QueryIteratorWrapper.java:40)
>>>> at
>>>> com.hp.hpl.jena.sparql.engine.**iterator.QueryIteratorBase.**
>>>> hasNext(QueryIteratorBase.**java:108)
>>>> at
>>>> com.hp.hpl.jena.sparql.engine.**ResultSetStream.hasNext(**
>>>> ResultSetStream.java:72)
>>>> at Query.main(Query.java:34)
>>>> Caused by: java.net.**NoRouteToHostException: Cannot assign requested
>>>> address
>>>> at java.net.PlainSocketImpl.**socketConnect(Native Method)
>>>> at
>>>> java.net.**AbstractPlainSocketImpl.**doConnect(**
>>>> AbstractPlainSocketImpl.java:**327)
>>>> at
>>>> java.net.**AbstractPlainSocketImpl.**connectToAddress(**
>>>> AbstractPlainSocketImpl.java:**193)
>>>> at
>>>> java.net.**AbstractPlainSocketImpl.**connect(**
>>>> AbstractPlainSocketImpl.java:**180)
>>>> at java.net.SocksSocketImpl.**connect(SocksSocketImpl.java:**384)
>>>> at java.net.Socket.connect(**Socket.java:546)
>>>> at java.net.Socket.connect(**Socket.java:495)
>>>> at sun.net.NetworkClient.**doConnect(NetworkClient.java:**178)
>>>> at sun.net.www.http.HttpClient.**openServer(HttpClient.java:**409)
>>>> at sun.net.www.http.HttpClient.**openServer(HttpClient.java:**530)
>>>> at sun.net.www.http.HttpClient.<**init>(HttpClient.java:240)
>>>> at sun.net.www.http.HttpClient.**New(HttpClient.java:321)
>>>> at sun.net.www.http.HttpClient.**New(HttpClient.java:338)
>>>> at
>>>> sun.net.www.protocol.http.**HttpURLConnection.**getNewHttpClient(**
>>>> HttpURLConnection.java:935)
>>>> at
>>>> sun.net.www.protocol.http.**HttpURLConnection.**plainConnect(**
>>>> HttpURLConnection.java:876)
>>>> at
>>>> sun.net.www.protocol.http.**HttpURLConnection.connect(**
>>>> HttpURLConnection.java:801)
>>>> at
>>>> com.hp.hpl.jena.sparql.engine.**http.HttpQuery.execGet(**
>>>> HttpQuery.java:199)
>>>> ... 14 more
>>>>
>>>> Best regards,
>>>> Regis.
>>>>
>>>>
>>>>
>>>
>>
>
