fix: concurrency bug in Blazegraph

Dockerfile

@@ -2,12 +2,15 @@
 # 1) docker build -t vaimeedock/sepa:latest -f Dockerfile .
 # 2) docker login -u YOUR-USER-NAME.
 # Build command on Apple M1: docker buildx build --platform linux/amd64 --push -t vaimeedock/engine .
-FROM maven:3.6-jdk-13 as BUILD
+FROM maven:3.6-jdk-11 as BUILD
 COPY . .
 
+ENV  JMX_HOSTNAME=0.0.0.0
+ENV  JMX_PORT=7090
+
 RUN mvn clean package
 
-FROM openjdk:13-jdk-alpine
+FROM openjdk:11.0-jre
 
 COPY --from=BUILD ./engine/target/engine-1.0.0-SNAPSHOT.jar /engine.jar
 COPY --from=BUILD ./engine/src/main/resources/jmxremote.password /jmxremote.password
@@ -19,9 +22,6 @@ COPY --from=BUILD ./engine/src/main/resources/endpoints /endpoints
 
 RUN chmod 600 /jmxremote.password
 
-ENV  JMX_HOSTNAME=0.0.0.0
-ENV  JMX_PORT=7090
-
 EXPOSE 8000
 EXPOSE 9000
 EXPOSE ${JMX_PORT}

engine/src/main/java/it/unibo/arces/wot/sepa/engine/core/Engine.java

@@ -41,7 +41,7 @@
  */
 
 public class Engine implements EngineMBean {
-	private final static String version = "0.13.0";
+	private final static String version = "v0.14.3";
 
 	private EngineProperties properties = null;
 

engine/src/main/java/it/unibo/arces/wot/sepa/engine/processing/QueryProcessor.java

@@ -45,6 +45,7 @@ public QueryProcessor(SPARQL11Properties properties) throws SEPAProtocolExceptio
 		SEPABeans.registerMBean("SEPA:type=" + this.getClass().getSimpleName(), this);
 
 		if (properties.getProtocolScheme().equals("jena-api") && properties.getHost().equals("in-memory")) endpoint = new JenaInMemoryEndpoint();
+		else endpoint = new RemoteEndpoint();
 	}
 
 	public Response process(InternalQueryRequest req) throws SEPASecurityException, IOException {
@@ -59,9 +60,7 @@ public Response process(InternalQueryRequest req) throws SEPASecurityException,
 		Response ret;
 		do {
 			long start = Timings.getTime();
-			if (!(properties.getProtocolScheme().equals("jena-api") && properties.getHost().equals("in-memory"))) endpoint = new RemoteEndpoint();
 			ret = endpoint.query(request);
-			endpoint.close();
 			long stop = Timings.getTime();
 
 			UpdateProcessorBeans.timings(start, stop);

engine/src/main/java/it/unibo/arces/wot/sepa/engine/processing/UpdateProcessor.java

@@ -45,6 +45,7 @@ public UpdateProcessor(SPARQL11Properties properties) throws SEPAProtocolExcepti
 		SEPABeans.registerMBean("SEPA:type=" + this.getClass().getSimpleName(), this);
 
 		if (properties.getProtocolScheme().equals("jena-api") && properties.getHost().equals("in-memory")) endpoint = new JenaInMemoryEndpoint();
+		else endpoint = new RemoteEndpoint();
 	}
 
 	public Response process(InternalUpdateRequest req) throws SEPASecurityException, IOException {
@@ -59,9 +60,7 @@ public Response process(InternalUpdateRequest req) throws SEPASecurityException,
 		int n = 0;
 		do {
 			long start = Timings.getTime();
-			if (!(properties.getProtocolScheme().equals("jena-api") && properties.getHost().equals("in-memory"))) endpoint = new RemoteEndpoint();
 			ret = endpoint.update(request);
-			endpoint.close();
 			long stop = Timings.getTime();
 
 			UpdateProcessorBeans.timings(start, stop);

engine/src/main/java/it/unibo/arces/wot/sepa/engine/processing/endpoint/JenaInMemoryEndpoint.java

@@ -102,9 +102,4 @@ public Response update(UpdateRequest req) {
 		});
 		return new UpdateResponse("Jena-in-memory-update");
 	}
-
-	@Override
-	public void close() {
-
-	}
 }

engine/src/main/java/it/unibo/arces/wot/sepa/engine/processing/endpoint/RemoteEndpoint.java

@@ -1,13 +1,10 @@
 package it.unibo.arces.wot.sepa.engine.processing.endpoint;
 
-import java.io.IOException;
-
 import it.unibo.arces.wot.sepa.api.SPARQL11Protocol;
 import it.unibo.arces.wot.sepa.commons.exceptions.SEPASecurityException;
 import it.unibo.arces.wot.sepa.commons.request.QueryRequest;
 import it.unibo.arces.wot.sepa.commons.request.UpdateRequest;
 import it.unibo.arces.wot.sepa.commons.response.Response;
-import it.unibo.arces.wot.sepa.logging.Logging;
 
 public class RemoteEndpoint implements SPARQLEndpoint {
 	SPARQL11Protocol endpoint;
@@ -26,13 +23,4 @@ public Response update(UpdateRequest req) {
 		return endpoint.update(req);
 	}
 
-	@Override
-	public void close() {
-		try {
-			endpoint.close();
-		} catch (IOException e) {
-			Logging.logger.error(e.getMessage());
-		}
-	}
-
 }

engine/src/main/java/it/unibo/arces/wot/sepa/engine/processing/endpoint/SPARQLEndpoint.java

@@ -7,5 +7,4 @@
 public interface SPARQLEndpoint {
 	public Response query(QueryRequest req);
 	public Response update(UpdateRequest req);
-	public void close();
 }

engine/src/main/java/it/unibo/arces/wot/sepa/engine/processing/subscriptions/SPUNaive.java

@@ -81,7 +81,7 @@ public Notification postUpdateInternalProcessing(UpdateResponse res) throws SEPA
 			ret = manager.processQuery(subscribe);
 		} catch (SEPASecurityException | IOException e) {
 			if (Logging.logger.isTraceEnabled()) e.printStackTrace();
-			Logging.logger.log(Logging.getLevel("spu"),"SEPASecurityException "+e.getMessage());
+			Logging.logger.log(Logging.getLevel("spu"),"Exception on query procesing "+e.getMessage());
 			throw new SEPAProcessingException("postUpdateInternalProcessing exception "+e.getMessage());
 		}
 

pom.xml

@@ -12,6 +12,13 @@
 	</modules>
 	<name>SEPA Project</name>
 	<url>https://github.com/vaimee/SEPA.git</url>
+	<properties>
+		<maven.compiler.source>11</maven.compiler.source>
+		<maven.compiler.target>11</maven.compiler.target>
+		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+		<revision>1.0.0-SNAPSHOT</revision>
+		<update>0</update>
+	</properties>
 	<licenses>
 		<license>
 			<name>GNU Lesser General Public License v3.0</name>
@@ -43,13 +50,7 @@
 		<developerConnection>scm:git:ssh://github.com/vaimee/sepa.git</developerConnection>
 		<url>https://github.com/vaimee/SEPA</url>
 	</scm>
-	<properties>
-		<maven.compiler.source>13</maven.compiler.source>
-		<maven.compiler.target>13</maven.compiler.target>
-		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-		<revision>v0.14.0</revision>
-		<update>0</update>
-	</properties>
+
 	<distributionManagement>
 		<repository>
 			<id>github</id>