HHH-18806 attempt to make handling of Clob/NClob more robust

Signed-off-by: Gavin King <[email protected]>

Author: gavinking

hibernate-core/src/main/java/org/hibernate/dialect/Dialect.java

@@ -3777,12 +3777,12 @@ public boolean useInputStreamToInsertBlob() {
 	}
 
 	/**
-	 * Should BLOB, CLOB, and NCLOB be created solely using respectively
-	 * {@link Connection#createBlob()}, {@link Connection#createClob()},
-	 * and {@link Connection#createNClob()}.
+	 * Should {@link Blob}, {@link Clob}, and {@link NClob} be created solely
+	 * using {@link Connection#createBlob()}, {@link Connection#createClob()},
+	 * and {@link Connection#createNClob()}, instead of allowing the use of
+	 * our own implementations.
 	 *
-	 * @return True if BLOB, CLOB, and NCLOB should be created using JDBC
-	 * {@link Connection}.
+	 * @return True if these types should be instantiated using {@link Connection}.
 	 *
 	 * @since 6.6
 	 */

hibernate-core/src/main/java/org/hibernate/dialect/SybaseDialect.java

@@ -58,6 +58,7 @@
 import org.hibernate.type.descriptor.jdbc.BlobJdbcType;
 import org.hibernate.type.descriptor.jdbc.ClobJdbcType;
 import org.hibernate.type.descriptor.jdbc.JdbcType;
+import org.hibernate.type.descriptor.jdbc.NClobJdbcType;
 import org.hibernate.type.descriptor.jdbc.ObjectNullAsBinaryTypeJdbcType;
 import org.hibernate.type.descriptor.jdbc.TinyIntAsSmallIntJdbcType;
 import org.hibernate.type.descriptor.jdbc.spi.JdbcTypeRegistry;
@@ -213,7 +214,7 @@ public void contributeTypes(TypeContributions typeContributions, ServiceRegistry
 
 			// The jTDS driver doesn't support the JDBC4 signatures using 'long length' for stream bindings
 			jdbcTypeRegistry.addDescriptor( Types.CLOB, ClobJdbcType.CLOB_BINDING );
-			jdbcTypeRegistry.addDescriptor( Types.NCLOB, ClobJdbcType.CLOB_BINDING );
+			jdbcTypeRegistry.addDescriptor( Types.NCLOB, NClobJdbcType.NCLOB_BINDING );
 		}
 		else {
 			// jConnect driver only conditionally supports getClob/getNClob depending on a server setting. See

hibernate-core/src/main/java/org/hibernate/engine/jdbc/AbstractLobCreator.java

@@ -3,12 +3,14 @@
  * Copyright Red Hat Inc. and Hibernate Authors
  */
 package org.hibernate.engine.jdbc;
+
+
 import java.sql.Blob;
 import java.sql.Clob;
 import java.sql.NClob;
 
 /**
- * Convenient base class for proxy-based LobCreator for handling wrapping.
+ * Convenient base class for proxy-based {@link LobCreator} for handling wrapping.
  *
  * @author Steve Ebersole
  */
@@ -20,16 +22,28 @@ public Blob wrap(Blob blob) {
 
 	@Override
 	public Clob wrap(Clob clob) {
-		if ( clob instanceof NClob ) {
-			return wrap( (NClob) clob );
-		}
-		else {
-			return SerializableClobProxy.generateProxy( clob );
-		}
+		return clob instanceof NClob nclob
+				? wrap( nclob )
+				: SerializableClobProxy.generateProxy( clob );
 	}
 
 	@Override
 	public NClob wrap(NClob nclob) {
 		return SerializableNClobProxy.generateProxy( nclob );
 	}
+
+	@Override
+	public Blob createBlob(Blob blob) {
+		return blob;
+	}
+
+	@Override
+	public Clob createClob(Clob clob) {
+		return clob;
+	}
+
+	@Override
+	public NClob createNClob(NClob clob) {
+		return clob;
+	}
 }

hibernate-core/src/main/java/org/hibernate/engine/jdbc/BinaryStream.java

@@ -5,6 +5,7 @@
 package org.hibernate.engine.jdbc;
 
 import java.io.InputStream;
+import java.sql.Blob;
 
 /**
  * Wraps a binary stream to also provide the length which is needed when binding.
@@ -37,4 +38,12 @@ public interface BinaryStream {
 	 * Release any underlying resources.
 	 */
 	void release();
+
+	/**
+	 * Use the given {@link LobCreator} to create a {@link Blob}
+	 * with the same data as this binary stream.
+	 *
+	 * @since 7.0
+	 */
+	Blob asBlob(LobCreator lobCreator);
 }

hibernate-core/src/main/java/org/hibernate/engine/jdbc/BlobProxy.java

@@ -11,7 +11,8 @@
 import java.sql.SQLException;
 
 import org.hibernate.Internal;
-import org.hibernate.engine.jdbc.internal.BinaryStreamImpl;
+import org.hibernate.engine.jdbc.internal.ArrayBackedBinaryStream;
+import org.hibernate.engine.jdbc.internal.StreamBackedBinaryStream;
 import org.hibernate.type.descriptor.java.DataHelper;
 
 /**
@@ -45,7 +46,7 @@ public final class BlobProxy implements Blob, BlobImplementer {
 	 * @see #generateProxy(byte[])
 	 */
 	private BlobProxy(byte[] bytes) {
-		binaryStream = new BinaryStreamImpl( bytes );
+		binaryStream = new ArrayBackedBinaryStream( bytes );
 	}
 
 	/**
@@ -179,45 +180,6 @@ public InputStream getBinaryStream(final long start, final long length) throws S
 		return DataHelper.subStream( getStream(), start-1, intLength );
 	}
 
-	private static class StreamBackedBinaryStream implements BinaryStream {
-
-		private final InputStream stream;
-		private final long length;
-		private byte[] bytes;
-
-		private StreamBackedBinaryStream(InputStream stream, long length) {
-			this.stream = stream;
-			this.length = length;
-		}
-
-		@Override
-		public InputStream getInputStream() {
-			return stream;
-		}
-
-		@Override
-		public byte[] getBytes() {
-			if ( bytes == null ) {
-				bytes = DataHelper.extractBytes( stream );
-			}
-			return bytes;
-		}
-
-		@Override
-		public long getLength() {
-			return length;
-		}
-
-		@Override
-		public void release() {
-			try {
-				stream.close();
-			}
-			catch (IOException ignore) {
-			}
-		}
-	}
-
 	private static UnsupportedOperationException notSupported() {
 		return new UnsupportedOperationException( "Blob may not be manipulated from creating session" );
 	}

hibernate-core/src/main/java/org/hibernate/engine/jdbc/LobCreator.java

@@ -100,4 +100,8 @@ public interface LobCreator {
 	 * environments, also castable to java.sql.NClob
 	 */
 	NClob createNClob(Reader reader, long length);
+
+	Blob createBlob(Blob clob);
+	Clob createClob(Clob clob);
+	NClob createNClob(NClob clob);
 }

hibernate-core/src/main/java/org/hibernate/engine/jdbc/env/internal/BlobAndClobCreator.java

@@ -20,7 +20,7 @@
 import org.hibernate.engine.jdbc.NonContextualLobCreator;
 
 /**
- * LobCreator which can use {@link Connection#createBlob} and {@link Connection#createClob},
+ * {@link LobCreator} which can use {@link Connection#createBlob} and {@link Connection#createClob},
  * but {@link java.sql.NClob} references are created locally.
  *
  * @see NClobProxy
@@ -40,9 +40,11 @@ public class BlobAndClobCreator extends AbstractLobCreator implements LobCreator
 	public static final LobCreationContext.Callback<Clob> CREATE_CLOB_CALLBACK = Connection::createClob;
 
 	protected final LobCreationContext lobCreationContext;
+	protected final boolean useConnectionToCreateLob;
 
-	public BlobAndClobCreator(LobCreationContext lobCreationContext) {
+	public BlobAndClobCreator(LobCreationContext lobCreationContext, boolean useConnectionToCreateLob) {
 		this.lobCreationContext = lobCreationContext;
+		this.useConnectionToCreateLob = useConnectionToCreateLob;
 	}
 
 	/**
@@ -68,8 +70,9 @@ public Blob createBlob(byte[] bytes) {
 
 	@Override
 	public Blob createBlob(InputStream stream, long length) {
-		// IMPL NOTE : it is inefficient to use JDBC LOB locator creation to create a LOB
-		// backed by a given stream.  So just wrap the stream (which is what the NonContextualLobCreator does).
+		// IMPL NOTE: it's inefficient to use JDBC LOB locator creation to
+		// create a LOB backed by a given stream. So just wrap the stream
+		// (which is what the NonContextualLobCreator does).
 		return NonContextualLobCreator.INSTANCE.createBlob( stream, length );
 	}
 
@@ -96,8 +99,9 @@ public Clob createClob(String string) {
 
 	@Override
 	public Clob createClob(Reader reader, long length) {
-		// IMPL NOTE : it is inefficient to use JDBC LOB locator creation to create a LOB
-		// backed by a given stream.  So just wrap the stream (which is what the NonContextualLobCreator does).
+		// IMPL NOTE: it's inefficient to use JDBC LOB locator creation to
+		// create a LOB backed by a given stream. So just wrap the stream
+		// (which is what the NonContextualLobCreator does).
 		return NonContextualLobCreator.INSTANCE.createClob( reader, length );
 	}
 
@@ -110,4 +114,40 @@ public NClob createNClob(String string) {
 	public NClob createNClob(Reader reader, long length) {
 		return NonContextualLobCreator.INSTANCE.createNClob( reader, length );
 	}
+
+	@Override
+	public Blob createBlob(Blob blob) {
+		try {
+			return useConnectionToCreateLob
+					? createBlob( blob.getBytes( 1, (int) blob.length() ) )
+					: blob;
+		}
+		catch (SQLException e) {
+			throw new JDBCException( "Could not create JDBC Clob", e );
+		}
+	}
+
+	@Override
+	public Clob createClob(Clob clob) {
+		try {
+			return useConnectionToCreateLob
+					? createClob( clob.getSubString( 1, (int) clob.length() ) )
+					: clob;
+		}
+		catch (SQLException e) {
+			throw new JDBCException( "Could not create JDBC Clob", e );
+		}
+	}
+
+	@Override
+	public NClob createNClob(NClob clob) {
+		try {
+			return useConnectionToCreateLob
+					? createNClob( clob.getSubString( 1, (int) clob.length() ) )
+					: clob;
+		}
+		catch (SQLException e) {
+			throw new JDBCException( "Could not create JDBC Clob", e );
+		}
+	}
 }

hibernate-core/src/main/java/org/hibernate/engine/jdbc/env/internal/JdbcEnvironmentImpl.java

@@ -35,6 +35,8 @@
 
 import org.jboss.logging.Logger;
 
+import static org.hibernate.engine.jdbc.env.internal.LobCreatorBuilderImpl.makeLobCreatorBuilder;
+
 /**
  * @author Steve Ebersole
  */
@@ -100,7 +102,7 @@ public JdbcEnvironmentImpl(final ServiceRegistryImplementor serviceRegistry, fin
 
 		this.qualifiedObjectNameFormatter = new QualifiedObjectNameFormatterStandardImpl( nameQualifierSupport );
 
-		this.lobCreatorBuilder = LobCreatorBuilderImpl.makeLobCreatorBuilder();
+		this.lobCreatorBuilder = makeLobCreatorBuilder( dialect );
 	}
 
 	private IdentifierHelperBuilder identifierHelperBuilder(
@@ -201,7 +203,7 @@ public JdbcEnvironmentImpl(
 				databaseMetaData
 		);
 
-		this.lobCreatorBuilder = LobCreatorBuilderImpl.makeLobCreatorBuilder();
+		this.lobCreatorBuilder = makeLobCreatorBuilder( dialect );
 	}
 
 	private IdentifierHelper identifierHelper(DatabaseMetaData databaseMetaData, Dialect dialect) {

hibernate-core/src/main/java/org/hibernate/engine/jdbc/env/internal/LobCreatorBuilderImpl.java

@@ -25,9 +25,11 @@
  * @author Steve Ebersole
  */
 public class LobCreatorBuilderImpl implements LobCreatorBuilder {
+	private final boolean useConnectionToCreateLob;
 	private final EnumSet<LobTypes> supportedContextualLobTypes;
 
-	public LobCreatorBuilderImpl(EnumSet<LobTypes> supportedContextualLobTypes) {
+	public LobCreatorBuilderImpl(boolean useConnectionToCreateLob, EnumSet<LobTypes> supportedContextualLobTypes) {
+		this.useConnectionToCreateLob = useConnectionToCreateLob;
 		this.supportedContextualLobTypes = supportedContextualLobTypes;
 	}
 
@@ -46,23 +48,18 @@ public static LobCreatorBuilderImpl makeLobCreatorBuilder(
 			Dialect dialect,
 			Map<String,Object> configValues,
 			Connection jdbcConnection) {
-		final EnumSet<LobTypes> supportedContextualLobTypes = getSupportedContextualLobTypes(
-				dialect,
-				configValues,
-				jdbcConnection
-		);
-
-		return new LobCreatorBuilderImpl( supportedContextualLobTypes );
+		return new LobCreatorBuilderImpl( dialect.useConnectionToCreateLob(),
+				getSupportedContextualLobTypes( dialect, configValues, jdbcConnection ) );
 	}
 
 	/**
 	 * For used when JDBC Connection is not available.
 	 *
 	 * @return Appropriate LobCreatorBuilder
 	 */
-	public static LobCreatorBuilderImpl makeLobCreatorBuilder() {
+	public static LobCreatorBuilderImpl makeLobCreatorBuilder(Dialect dialect) {
 		LOB_MESSAGE_LOGGER.disablingContextualLOBCreationSinceConnectionNull();
-		return new LobCreatorBuilderImpl( NONE );
+		return new LobCreatorBuilderImpl( dialect.useConnectionToCreateLob(), NONE );
 	}
 
 	/**
@@ -76,17 +73,18 @@ public LobCreator buildLobCreator(LobCreationContext lobCreationContext) {
 		if ( supportedContextualLobTypes.isEmpty() ) {
 			return NonContextualLobCreator.INSTANCE;
 		}
-
-		if ( supportedContextualLobTypes.contains( LobTypes.BLOB )
+		else if ( supportedContextualLobTypes.contains( LobTypes.BLOB )
 				&& supportedContextualLobTypes.contains( LobTypes.CLOB ) ){
 			if ( !supportedContextualLobTypes.contains( LobTypes.NCLOB ) ) {
-				return new BlobAndClobCreator( lobCreationContext );
+				return new BlobAndClobCreator( lobCreationContext, useConnectionToCreateLob );
+			}
+			else {
+				return new StandardLobCreator( lobCreationContext, useConnectionToCreateLob );
 			}
-
-			return new StandardLobCreator( lobCreationContext );
 		}
-
-		LOB_LOGGER.debug( "Unexpected condition resolving type of LobCreator to use. Falling back to NonContextualLobCreator" );
-		return NonContextualLobCreator.INSTANCE;
+		else {
+			LOB_LOGGER.debug( "Unexpected condition resolving type of LobCreator to use. Falling back to NonContextualLobCreator" );
+			return NonContextualLobCreator.INSTANCE;
+		}
 	}
 }

hibernate-core/src/main/java/org/hibernate/engine/jdbc/env/internal/StandardLobCreator.java

@@ -28,8 +28,8 @@ public class StandardLobCreator extends BlobAndClobCreator {
 	 */
 	public static final LobCreationContext.Callback<NClob> CREATE_NCLOB_CALLBACK = Connection::createNClob;
 
-	public StandardLobCreator(LobCreationContext lobCreationContext) {
-		super( lobCreationContext );
+	public StandardLobCreator(LobCreationContext lobCreationContext, boolean useConnectionToCreateLob) {
+		super( lobCreationContext, useConnectionToCreateLob );
 	}
 
 	/**