GH-5108 add a java system property to modify the limit for when we can still use SPARQL validation approach with sh:maxCount (#5109)

Author: hmottestad

core/sail/shacl/src/main/java/org/eclipse/rdf4j/sail/shacl/ast/constraintcomponents/MaxCountConstraintComponent.java

@@ -44,9 +44,20 @@
 import org.eclipse.rdf4j.sail.shacl.ast.planNodes.ValidationTuple;
 import org.eclipse.rdf4j.sail.shacl.ast.targets.EffectiveTarget;
 import org.eclipse.rdf4j.sail.shacl.wrapper.data.ConnectionsGroup;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 public class MaxCountConstraintComponent extends AbstractConstraintComponent {
 
+	private static final Logger logger = LoggerFactory.getLogger(MaxCountConstraintComponent.class);
+
+	// Performance degrades quickly as the maxCount increases when using a SPARQL Validation Approach. The default is 5,
+	// but it can be tuned using the system property below.
+	private static final String SPARQL_VALIDATION_APPROACH_LIMIT_PROPERTY = "org.eclipse.rdf4j.sail.shacl.ast.constraintcomponents.MaxCountConstraintComponent.sparqlValidationApproachLimit";
+	private static final long SPARQL_VALIDATION_APPROACH_LIMIT = System
+			.getProperty(SPARQL_VALIDATION_APPROACH_LIMIT_PROPERTY) == null ? 5
+					: Long.parseLong(System.getProperty(SPARQL_VALIDATION_APPROACH_LIMIT_PROPERTY));
+
 	private final long maxCount;
 
 	public MaxCountConstraintComponent(long maxCount) {
@@ -216,8 +227,12 @@ public ValidationQuery generateSparqlValidationQuery(ConnectionsGroup connection
 
 	@Override
 	public ValidationApproach getOptimalBulkValidationApproach() {
-		// performance of large maxCount is terrible
-		if (maxCount > 5) {
+		if (maxCount > SPARQL_VALIDATION_APPROACH_LIMIT) {
+			if (logger.isDebugEnabled()) {
+				logger.debug(
+						"maxCount is {}, which is greater than the limit of {}, using ValidationApproach.Transactional instead of ValidationApproach.SPARQL for {}",
+						maxCount, SPARQL_VALIDATION_APPROACH_LIMIT, stringRepresentationOfValue(getId()));
+			}
 			return ValidationApproach.Transactional;
 		}
 		return ValidationApproach.SPARQL;
@@ -244,6 +259,6 @@ public boolean equals(Object o) {
 
 	@Override
 	public int hashCode() {
-		return (int) (maxCount ^ (maxCount >>> 32)) + "MaxCountConstraintComponent".hashCode();
+		return Long.hashCode(maxCount) + "MaxCountConstraintComponent".hashCode();
 	}
 }

core/sail/shacl/src/main/java/org/eclipse/rdf4j/sail/shacl/ast/constraintcomponents/MaxLengthConstraintComponent.java

@@ -89,6 +89,6 @@ public boolean equals(Object o) {
 
 	@Override
 	public int hashCode() {
-		return (int) (maxLength ^ (maxLength >>> 32)) + "MaxLengthConstraintComponent".hashCode();
+		return Long.hashCode(maxLength) + "MaxLengthConstraintComponent".hashCode();
 	}
 }

core/sail/shacl/src/main/java/org/eclipse/rdf4j/sail/shacl/ast/constraintcomponents/MinCountConstraintComponent.java

@@ -227,6 +227,6 @@ public boolean equals(Object o) {
 
 	@Override
 	public int hashCode() {
-		return (int) (minCount ^ (minCount >>> 32)) + "MinCountConstraintComponent".hashCode();
+		return Long.hashCode(minCount) + "MinCountConstraintComponent".hashCode();
 	}
 }

core/sail/shacl/src/main/java/org/eclipse/rdf4j/sail/shacl/ast/constraintcomponents/MinLengthConstraintComponent.java

@@ -89,6 +89,6 @@ public boolean equals(Object o) {
 
 	@Override
 	public int hashCode() {
-		return (int) (minLength ^ (minLength >>> 32)) + "MinLengthConstraintComponent".hashCode();
+		return Long.hashCode(minLength) + "MinLengthConstraintComponent".hashCode();
 	}
 }