HHH-14725 Fix reset handling on BlobProxy

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

@@ -31,6 +31,8 @@
 public final class BlobProxy implements Blob, BlobImplementer {
 
 	private final BinaryStream binaryStream;
+	private final int markBytes;
+	private boolean resetAllowed;
 	private boolean needsReset;
 
 	/**
@@ -41,6 +43,8 @@ public final class BlobProxy implements Blob, BlobImplementer {
 	 */
 	private BlobProxy(byte[] bytes) {
 		binaryStream = new BinaryStreamImpl( bytes );
+		markBytes = bytes.length + 1;
+		setStreamMark();
 	}
 
 	/**
@@ -52,6 +56,18 @@ private BlobProxy(byte[] bytes) {
 	 */
 	private BlobProxy(InputStream stream, long length) {
 		this.binaryStream = new StreamBackedBinaryStream( stream, length );
+		this.markBytes = (int) length + 1;
+		setStreamMark();
+	}
+
+	private void setStreamMark() {
+		if ( binaryStream.getInputStream().markSupported() ) {
+			binaryStream.getInputStream().mark( markBytes );
+			resetAllowed = true;
+		}
+		else {
+			resetAllowed = false;
+		}
 	}
 
 
@@ -67,7 +83,12 @@ public BinaryStream getUnderlyingStream() throws SQLException {
 	private void resetIfNeeded() throws SQLException {
 		try {
 			if ( needsReset ) {
+				if ( !resetAllowed ) {
+					throw new SQLException( "Underlying stream does not allow reset" );
+				}
+
 				binaryStream.getInputStream().reset();
+				setStreamMark();
 			}
 		}
 		catch ( IOException ioe) {
@@ -90,6 +111,11 @@ public static Blob generateProxy(byte[] bytes) {
 	/**
 	 * Generates a BlobImpl proxy using a given number of bytes from an InputStream.
 	 *
+	 * Be aware that certain database drivers will automatically close the provided InputStream after the
+	 * contents have been written to the database.  This may cause unintended side effects if the entity
+	 * is also audited by Envers.  In this case, it's recommended to use {@link #generateProxy(byte[])}
+	 * instead as it isn't affected by this non-standard behavior.
+	 *
 	 * @param stream The input stream of bytes to be created as a Blob.
 	 * @param length The number of bytes from stream to be written to the Blob.
 	 *

hibernate-envers/src/test/java/org/hibernate/orm/test/envers/integration/blob/BasicBlobTest.java

@@ -0,0 +1,111 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.orm.test.envers.integration.blob;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hibernate.testing.transaction.TransactionUtil.doInJPA;
+import static org.junit.Assert.fail;
+
+import java.io.BufferedInputStream;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.sql.Blob;
+
+import org.hamcrest.Matchers;
+import org.hibernate.engine.jdbc.BlobProxy;
+import org.hibernate.envers.Audited;
+import org.hibernate.orm.test.envers.BaseEnversJPAFunctionalTestCase;
+import org.hibernate.orm.test.envers.Priority;
+import org.junit.Test;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+
+/**
+ * @author Chris Cranford
+ */
+public class BasicBlobTest extends BaseEnversJPAFunctionalTestCase {
+
+	@Override
+	protected Class<?>[] getAnnotatedClasses() {
+		return new Class<?>[] { Asset.class };
+	}
+
+	@Test
+	@Priority(10)
+	public void initData() {
+		final Path path = Path.of( getClass().getResource( "./blob.txt" ).getPath() );
+		doInJPA( this::entityManagerFactory, entityManager -> {
+			try {
+				final Asset asset = new Asset();
+				asset.setFileName( "blob.txt" );
+
+				final InputStream stream = new BufferedInputStream( Files.newInputStream( path ) );
+				assertThat( stream.markSupported(), Matchers.is( true ) );
+
+				// We use the method readAllBytes instead of passing the raw stream to the proxy
+				// since this is the only guaranteed way that will work across all dialects in a
+				// deterministic way.  Postgres and Sybase will automatically close the stream
+				// after the blob has been written by the driver, which prevents Envers from
+				// then writing the contents of the stream to the audit table.
+				//
+				// If the driver and dialect are known not to close the input stream after the
+				// contents have been written by the driver, then it's safe to pass the stream
+				// here instead and the stream will be automatically marked and reset so that
+				// Envers can serialize the data after Hibernate has done so.  Dialects like
+				// H2, MySQL, Oracle, SQL Server work this way.
+				//
+				//
+				Blob blob = BlobProxy.generateProxy( stream.readAllBytes() );
+
+				asset.setData( blob );
+				entityManager.persist( asset );
+			}
+			catch (Exception e) {
+				e.printStackTrace();
+				fail( "Failed to persist the entity" );
+			}
+		} );
+	}
+
+	@Audited
+	@Entity(name = "Asset")
+	public static class Asset {
+		@Id
+		@GeneratedValue
+		private Integer id;
+		private String fileName;
+		private Blob data;
+
+		public Integer getId() {
+			return id;
+		}
+
+		public void setId(Integer id) {
+			this.id = id;
+		}
+
+		public String getFileName() {
+			return fileName;
+		}
+
+		public void setFileName(String fileName) {
+			this.fileName = fileName;
+		}
+
+		public Blob getData() {
+			return data;
+		}
+
+		public void setData(Blob data) {
+			this.data = data;
+		}
+	}
+
+}

hibernate-envers/src/test/java/org/hibernate/orm/test/envers/integration/blob/blob.txt

@@ -0,0 +1,33 @@
+<?xml version='1.0' encoding='utf-8'?>
+<!--
+  ~ Hibernate, Relational Persistence for Idiomatic Java
+  ~
+  ~ License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+  ~ See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+  -->
+<!DOCTYPE hibernate-configuration PUBLIC
+        "-//Hibernate/Hibernate Configuration DTD//EN"
+        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
+
+<hibernate-configuration>
+    <session-factory>
+        <property name="hbm2ddl.auto">create-drop</property>
+
+        <property name="show_sql">false</property>
+        <property name="format_sql">false</property>
+
+        <property name="dialect">org.hibernate.dialect.H2Dialect</property>
+        <property name="connection.url">jdbc:h2:mem:envers</property>
+        <property name="connection.driver_class">org.h2.Driver</property>
+        <property name="connection.username">sa</property>
+        <property name="connection.password"></property>
+
+        <!--<property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>-->
+        <!--<property name="connection.url">jdbc:mysql:///hibernate_tests?useUnicode=true&amp;characterEncoding=UTF-8</property>-->
+        <!--<property name="connection.driver_class">com.mysql.jdbc.Driver</property>-->
+        <!--<property name="connection.username">root</property>-->
+        <!--<property name="connection.password"></property>-->
+
+        <!--<property name="hibernate.jdbc.batch_size">100</property>-->
+    </session-factory>
+</hibernate-configuration>