remove hibernate.query.conventional_java_constants

this was apparently a sorta nasty bandaid to a performance problem in query compilation
and it caused problems for some users, breaking interpretation of enum values

documentation/src/main/asciidoc/userguide/appendices/Configurations.adoc

@@ -564,16 +564,6 @@ It follows a pattern similar to the ANSI SQL definition of the global temporary
 +
 This configuration property defines the database catalog used for storing the temporary tables used for bulk HQL operations.
 
-`*hibernate.query.conventional_java_constants*` (e.g. `true` (default value) or `false`)::
-Setting which indicates whether or not Java constants follow the https://docs.oracle.com/javase/tutorial/java/nutsandbolts/variables.html[Java Naming conventions].
-+
-The default is `true`.
-Existing applications may want to disable this (set it `false`) if non-conventional Java constants are used.
-However, there is a significant performance overhead for using non-conventional Java constants
-since Hibernate cannot determine if aliases should be treated as Java constants or not.
-+
-Check out https://hibernate.atlassian.net/browse/HHH-4959[HHH-4959] for more details.
-
 [[configurations-batch]]
 === Batching properties
 

hibernate-core/src/main/java/org/hibernate/boot/internal/SessionFactoryOptionsBuilder.java

@@ -90,7 +90,6 @@ import static org.hibernate.cfg.AvailableSettings.CACHE_REGION_PREFIX;
 import static org.hibernate.cfg.AvailableSettings.CALLABLE_NAMED_PARAMS_ENABLED;
 import static org.hibernate.cfg.AvailableSettings.CHECK_NULLABILITY;
 import static org.hibernate.cfg.AvailableSettings.CONNECTION_HANDLING;
-import static org.hibernate.cfg.AvailableSettings.CONVENTIONAL_JAVA_CONSTANTS;
 import static org.hibernate.cfg.AvailableSettings.CRITERIA_VALUE_HANDLING_MODE;
 import static org.hibernate.cfg.AvailableSettings.CUSTOM_ENTITY_DIRTINESS_STRATEGY;
 import static org.hibernate.cfg.AvailableSettings.DEFAULT_BATCH_FETCH_SIZE;
@@ -220,7 +219,6 @@ public class SessionFactoryOptionsBuilder implements SessionFactoryOptions {
 	private SqmTranslatorFactory sqmTranslatorFactory;
 	private Boolean useOfJdbcNamedParametersEnabled;
 	private boolean namedQueryStartupCheckingEnabled;
-	private boolean conventionalJavaConstants;
 	private final boolean omitJoinOfSuperclassTablesEnabled;
 	private final int preferredSqlTypeCodeForBoolean;
 	private final TimeZoneStorageStrategy defaultTimeZoneStorageStrategy;
@@ -441,14 +439,12 @@ public class SessionFactoryOptionsBuilder implements SessionFactoryOptions {
 		this.useOfJdbcNamedParametersEnabled = cfgService.getSetting( CALLABLE_NAMED_PARAMS_ENABLED, BOOLEAN, true );
 
 		this.namedQueryStartupCheckingEnabled = cfgService.getSetting( QUERY_STARTUP_CHECKING, BOOLEAN, true );
-		this.conventionalJavaConstants = cfgService.getSetting(
-				CONVENTIONAL_JAVA_CONSTANTS, BOOLEAN, true );
 		this.omitJoinOfSuperclassTablesEnabled = cfgService.getSetting( OMIT_JOIN_OF_SUPERCLASS_TABLES, BOOLEAN, true );
 		this.preferredSqlTypeCodeForBoolean = ConfigurationHelper.getPreferredSqlTypeCodeForBoolean( serviceRegistry );
 		this.defaultTimeZoneStorageStrategy = context.getMetadataBuildingOptions().getDefaultTimeZoneStorage();
 
 		final RegionFactory regionFactory = serviceRegistry.getService( RegionFactory.class );
-		if ( !NoCachingRegionFactory.class.isInstance( regionFactory ) ) {
+		if ( !(regionFactory instanceof NoCachingRegionFactory) ) {
 			this.secondLevelCacheEnabled = cfgService.getSetting( USE_SECOND_LEVEL_CACHE, BOOLEAN, true );
 			this.queryCacheEnabled = cfgService.getSetting( USE_QUERY_CACHE, BOOLEAN, false );
 			this.timestampsCacheFactory = strategySelector.resolveDefaultableStrategy(
@@ -1047,11 +1043,6 @@ public class SessionFactoryOptionsBuilder implements SessionFactoryOptions {
 		return namedQueryStartupCheckingEnabled;
 	}
 
-	@Override
-	public boolean isConventionalJavaConstants() {
-		return conventionalJavaConstants;
-	}
-
 	@Override
 	public boolean isSecondLevelCacheEnabled() {
 		return secondLevelCacheEnabled;

hibernate-core/src/main/java/org/hibernate/boot/spi/AbstractDelegatingSessionFactoryOptions.java

@@ -229,11 +229,6 @@ public class AbstractDelegatingSessionFactoryOptions implements SessionFactoryOp
 		return delegate.isNamedQueryStartupCheckingEnabled();
 	}
 
-	@Override
-	public boolean isConventionalJavaConstants() {
-		return delegate.isConventionalJavaConstants();
-	}
-
 	@Override
 	public boolean isAllowOutOfTransactionUpdateOperations() {
 		return delegate.isAllowOutOfTransactionUpdateOperations();

hibernate-core/src/main/java/org/hibernate/boot/spi/SessionFactoryOptions.java

@@ -189,8 +189,6 @@ public interface SessionFactoryOptions extends QueryEngineOptions {
 
 	boolean isNamedQueryStartupCheckingEnabled();
 
-	boolean isConventionalJavaConstants();
-
 	boolean isSecondLevelCacheEnabled();
 
 	boolean isQueryCacheEnabled();

hibernate-core/src/main/java/org/hibernate/cfg/AvailableSettings.java

@@ -985,18 +985,6 @@ public interface AvailableSettings {
 	 */
 	String QUERY_STARTUP_CHECKING = "hibernate.query.startup_check";
 
-	/**
-	 * Setting which indicates whether or not Java constant follow the Java Naming conventions.
-	 * <p/>
-	 * Default is {@code true}. Existing applications may want to disable this (set it {@code false})
-	 * if unconventional Java constants are used. However, there is a significant performance overhead
-	 * for using unconventional Java constants since Hibernate cannot determine if aliases should be
-	 * treated as Java constants or not.
-	 *
-	 * @since 5.2
-	 */
-	String CONVENTIONAL_JAVA_CONSTANTS = "hibernate.query.conventional_java_constants";
-
 	/**
 	 * Enable ordering of update statements by primary key value
 	 */

hibernate-core/src/main/java/org/hibernate/internal/util/ReflectHelper.java

@@ -254,28 +254,6 @@ public final class ReflectHelper {
 		return PropertyAccessStrategyMixedImpl.INSTANCE.buildPropertyAccess( clazz, name, true ).getGetter();
 	}
 
-	public static Object getConstantValue(String name, SessionFactoryImplementor factory) {
-		boolean conventionalJavaConstants = factory.getSessionFactoryOptions().isConventionalJavaConstants();
-		Class clazz;
-		try {
-			if ( conventionalJavaConstants &&
-				!JAVA_CONSTANT_PATTERN.matcher( name ).find() ) {
-				return null;
-			}
-			ClassLoaderService classLoaderService = factory.getServiceRegistry().getService( ClassLoaderService.class );
-			clazz = classLoaderService.classForName( StringHelper.qualifier( name ) );
-		}
-		catch ( Throwable t ) {
-			return null;
-		}
-		try {
-			return clazz.getField( StringHelper.unqualify( name ) ).get( null );
-		}
-		catch ( Throwable t ) {
-			return null;
-		}
-	}
-
 	/**
 	 * Retrieve the default (no arg) constructor from the given class.
 	 *

hibernate-core/src/test/java/org/hibernate/orm/test/internal/util/ReflectHelperTest.java

@@ -122,82 +122,6 @@ public class ReflectHelperTest {
 		when( serviceRegistryMock.getService( eq( ClassLoaderService.class ) ) ).thenReturn( classLoaderServiceMock );
 	}
 
-	@Test
-	public void test_getConstantValue_simpleAlias() {
-		when( sessionFactoryOptionsMock.isConventionalJavaConstants() ).thenReturn( true );
-
-		Object value = ReflectHelper.getConstantValue( "alias.b", sessionFactoryImplementorMock);
-		assertNull(value);
-		verify(classLoaderServiceMock, never()).classForName( anyString() );
-	}
-
-	@Test
-	public void test_getConstantValue_simpleAlias_non_conventional() {
-		when( sessionFactoryOptionsMock.isConventionalJavaConstants() ).thenReturn( false );
-
-		Object value = ReflectHelper.getConstantValue( "alias.b", sessionFactoryImplementorMock);
-		assertNull(value);
-		verify(classLoaderServiceMock, times(1)).classForName( eq( "alias" ) );
-	}
-
-	@Test
-	public void test_getConstantValue_nestedAlias() {
-		when( sessionFactoryOptionsMock.isConventionalJavaConstants() ).thenReturn( true );
-
-		Object value = ReflectHelper.getConstantValue( "alias.b.c", sessionFactoryImplementorMock);
-		assertNull(value);
-		verify(classLoaderServiceMock, never()).classForName( anyString() );
-	}
-
-	@Test
-	public void test_getConstantValue_nestedAlias_non_conventional() {
-		when( sessionFactoryOptionsMock.isConventionalJavaConstants() ).thenReturn( false );
-
-		Object value = ReflectHelper.getConstantValue( "alias.b.c", sessionFactoryImplementorMock);
-		assertNull(value);
-		verify(classLoaderServiceMock, times(1)).classForName( eq( "alias.b" ) );
-	}
-
-	@Test
-	public void test_getConstantValue_outerEnum() {
-		when( sessionFactoryOptionsMock.isConventionalJavaConstants() ).thenReturn( true );
-
-		when( classLoaderServiceMock.classForName( "jakarta.persistence.FetchType" ) ).thenReturn( (Class) FetchType.class );
-		Object value = ReflectHelper.getConstantValue( "jakarta.persistence.FetchType.LAZY", sessionFactoryImplementorMock);
-		assertEquals( FetchType.LAZY, value );
-		verify(classLoaderServiceMock, times(1)).classForName( eq("jakarta.persistence.FetchType") );
-	}
-
-	@Test
-	public void test_getConstantValue_enumClass() {
-		when( sessionFactoryOptionsMock.isConventionalJavaConstants() ).thenReturn( true );
-
-		when( classLoaderServiceMock.classForName( "org.hibernate.orm.test.internal.util.ReflectHelperTest$Status" ) ).thenReturn( (Class) Status.class );
-		Object value = ReflectHelper.getConstantValue( "org.hibernate.orm.test.internal.util.ReflectHelperTest$Status", sessionFactoryImplementorMock);
-		assertNull(value);
-		verify(classLoaderServiceMock, never()).classForName( eq("org.hibernate.internal.util") );
-	}
-
-	@Test
-	public void test_getConstantValue_nestedEnum() {
-
-		when( sessionFactoryOptionsMock.isConventionalJavaConstants() ).thenReturn( true );
-		when( classLoaderServiceMock.classForName( "org.hibernate.orm.test.internal.util.ReflectHelperTest$Status" ) ).thenReturn( (Class) Status.class );
-		Object value = ReflectHelper.getConstantValue( "org.hibernate.orm.test.internal.util.ReflectHelperTest$Status.ON", sessionFactoryImplementorMock);
-		assertEquals( ON, value );
-		verify(classLoaderServiceMock, times(1)).classForName( eq("org.hibernate.orm.test.internal.util.ReflectHelperTest$Status") );
-	}
-
-	@Test
-	public void test_getConstantValue_constant_digits() {
-
-		when( sessionFactoryOptionsMock.isConventionalJavaConstants() ).thenReturn( true );
-		when( classLoaderServiceMock.classForName( "org.hibernate.orm.test.internal.util.hib3rnat3.C0nst4nts३" ) ).thenReturn( (Class) C0nst4nts३.class );
-		Object value = ReflectHelper.getConstantValue( "org.hibernate.orm.test.internal.util.hib3rnat3.C0nst4nts३.ABC_DEF", sessionFactoryImplementorMock);
-		assertEquals( C0nst4nts३.ABC_DEF, value );
-		verify(classLoaderServiceMock, times(1)).classForName( eq("org.hibernate.orm.test.internal.util.hib3rnat3.C0nst4nts३") );
-	}
-
 	@Test
 	public void test_getMethod_nestedInterfaces() {
 		assertNotNull( ReflectHelper.findGetterMethod( C.class, "id" ) );
@@ -231,15 +155,4 @@ public class ReflectHelperTest {
 	public void test_setMethod_nestedInterfaces_on_superclasses() {
 		assertNotNull( ReflectHelper.findSetterMethod( E.class, "id", String.class ) );
 	}
-
-	@TestForIssue(jiraKey = "HHH-14059")
-	@Test
-	public void test_getConstantValue_UpperCaseEnum() {
-		when( sessionFactoryOptionsMock.isConventionalJavaConstants() ).thenReturn( true );
-
-		when( classLoaderServiceMock.classForName( "com.example.UStatus" ) ).thenReturn( (Class) Status.class );
-		Object value = ReflectHelper.getConstantValue( "com.example.UStatus.OFF", sessionFactoryImplementorMock);
-		assertEquals( OFF, value );
-		verify(classLoaderServiceMock, times(1)).classForName( eq("com.example.UStatus") );
-	}
 }