HHH-16815 Improvements in SqmInterpretationsKey

hibernate-core/src/main/java/org/hibernate/LockOptions.java

@@ -512,7 +512,7 @@ public class LockOptions implements Serializable {
 	}
 
 	/**
-	 * Make a copy.
+	 * Make a copy. The new copy will be mutable even if the original wasn't.
 	 *
 	 * @return The copy
 	 */
@@ -522,6 +522,22 @@ public class LockOptions implements Serializable {
 		return copy;
 	}
 
+	/**
+	 * Make a copy, unless this is an immutable instance.
+	 *
+	 * @return The copy, or this if it was immutable.
+	 */
+	public LockOptions makeDefensiveCopy() {
+		if ( immutable ) {
+			return this;
+		}
+		else {
+			final LockOptions copy = new LockOptions();
+			copy( this, copy );
+			return copy;
+		}
+	}
+
 	/**
 	 * Copy the given lock options into this instance,
 	 * merging the alias-specific lock modes.

hibernate-core/src/main/java/org/hibernate/query/sqm/internal/SqmInterpretationsKey.java

@@ -7,8 +7,10 @@
 package org.hibernate.query.sqm.internal;
 
 import java.util.Collection;
-import java.util.HashSet;
+import java.util.Iterator;
 import java.util.List;
+import java.util.Objects;
+import java.util.Set;
 import java.util.function.Supplier;
 
 import jakarta.persistence.criteria.Order;
@@ -26,7 +28,7 @@ import static org.hibernate.query.spi.AbstractSelectionQuery.CRITERIA_HQL_STRING
 /**
  * @author Steve Ebersole
  */
-public class SqmInterpretationsKey implements QueryInterpretationCache.Key {
+public final class SqmInterpretationsKey implements QueryInterpretationCache.Key {
 	public interface CacheabilityInfluencers {
 		boolean isQueryPlanCacheable();
 		String getQueryString();
@@ -43,16 +45,18 @@ public class SqmInterpretationsKey implements QueryInterpretationCache.Key {
 
 	public static SqmInterpretationsKey createInterpretationsKey(InterpretationsKeySource keySource) {
 		if ( isCacheable ( keySource ) ) {
-			return new SqmInterpretationsKey(
+			final Object query = CRITERIA_HQL_STRING.equals( keySource.getQueryString() )
-					CRITERIA_HQL_STRING.equals( keySource.getQueryString() )
 					? keySource.getSqmStatement()
-							: keySource.getQueryString(),
+					: keySource.getQueryString();
+			return new SqmInterpretationsKey(
+					query,
+					query.hashCode(),
 					keySource.getResultType(),
 					keySource.getOrder(),
 					keySource.getQueryOptions().getLockOptions(),
 					keySource.getQueryOptions().getTupleTransformer(),
 					keySource.getQueryOptions().getResultListTransformer(),
-					new HashSet<>( keySource.getLoadQueryInfluencers().getEnabledFetchProfileNames() )
+					memoryEfficientDefensiveSetCopy( keySource.getLoadQueryInfluencers().getEnabledFetchProfileNames() )
 			);
 		}
 		else {
@@ -60,6 +64,25 @@ public class SqmInterpretationsKey implements QueryInterpretationCache.Key {
 		}
 	}
 
+	private static Collection<String> memoryEfficientDefensiveSetCopy(final Set<String> set) {
+		if ( set == null ) {
+			return null;
+		}
+		else {
+			switch ( set.size() ) {
+				case 0:
+					return null;
+				case 1:
+					return Set.of( set.iterator().next() );
+				case 2:
+					final Iterator<String> iterator = set.iterator();
+					return Set.of( iterator.next(), iterator.next() );
+				default:
+					return Set.copyOf( set );
+			}
+		}
+	}
+
 	private static boolean isCacheable(InterpretationsKeySource keySource) {
 		assert keySource.getQueryOptions().getAppliedGraph() != null;
 
@@ -95,9 +118,11 @@ public class SqmInterpretationsKey implements QueryInterpretationCache.Key {
 	private final TupleTransformer<?> tupleTransformer;
 	private final ResultListTransformer<?> resultListTransformer;
 	private final Collection<String> enabledFetchProfiles;
+	private final int hashcode;
 
 	private SqmInterpretationsKey(
 			Object query,
+			int hash,
 			Class<?> resultType,
 			List<Order> order,
 			LockOptions lockOptions,
@@ -105,6 +130,7 @@ public class SqmInterpretationsKey implements QueryInterpretationCache.Key {
 			ResultListTransformer<?> resultListTransformer,
 			Collection<String> enabledFetchProfiles) {
 		this.query = query;
+		this.hashcode = hash;
 		this.resultType = resultType;
 		this.order = order;
 		this.lockOptions = lockOptions;
@@ -117,10 +143,11 @@ public class SqmInterpretationsKey implements QueryInterpretationCache.Key {
 	public QueryInterpretationCache.Key prepareForStore() {
 		return new SqmInterpretationsKey(
 				query,
+				hashcode,
 				resultType,
-				// Since lock options are mutable, we need a copy for the cache key
 				order,
-				lockOptions.makeCopy(),
+				// Since lock options might be mutable, we need a copy for the cache key
+				lockOptions.makeDefensiveCopy(),
 				tupleTransformer,
 				resultListTransformer,
 				enabledFetchProfiles
@@ -137,26 +164,23 @@ public class SqmInterpretationsKey implements QueryInterpretationCache.Key {
 		if ( this == o ) {
 			return true;
 		}
-		if ( o == null || getClass() != o.getClass() ) {
+		if ( o == null || SqmInterpretationsKey.class != o.getClass() ) {
 			return false;
 		}
 
 		final SqmInterpretationsKey that = (SqmInterpretationsKey) o;
-		return query.equals( that.query )
+		return this.hashcode == o.hashCode() //check this first as some other checks are expensive
-			&& areEqual( resultType, that.resultType )
+			&& query.equals( that.query )
-			&& areEqual( order, that.order )
+			&& Objects.equals( resultType, that.resultType )
-			&& areEqual( lockOptions, that.lockOptions )
+			&& Objects.equals( order, that.order )
-			&& areEqual( tupleTransformer, that.tupleTransformer )
+			&& Objects.equals( lockOptions, that.lockOptions )
-			&& areEqual( resultListTransformer, that.resultListTransformer )
+			&& Objects.equals( tupleTransformer, that.tupleTransformer )
-			&& areEqual( enabledFetchProfiles, that.enabledFetchProfiles );
+			&& Objects.equals( resultListTransformer, that.resultListTransformer )
-	}
+			&& Objects.equals( enabledFetchProfiles, that.enabledFetchProfiles );
-
-	private <T> boolean areEqual(T o1, T o2) {
-		return o1 == null ? o2 == null : o1.equals(o2);
 	}
 
 	@Override
 	public int hashCode() {
-		return query.hashCode();
+		return hashcode;
 	}
 }