ARTEMIS-1813 DB2 should avoid Blob to append data

(cherry picked from commit 998be38348b523dda744bba10826cc35a7e4b9d7)

artemis-jdbc-store/src/main/java/org/apache/activemq/artemis/jdbc/store/drivers/AbstractJDBCDriver.java

@@ -292,7 +292,7 @@ public abstract class AbstractJDBCDriver {
    }
 
    public final void setConnection(Connection connection) {
-      if (connection == null) {
+      if (this.connection == null) {
          this.connection = connection;
       }
    }

artemis-jdbc-store/src/main/java/org/apache/activemq/artemis/jdbc/store/file/Db2SequentialFileDriver.java

@@ -0,0 +1,79 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.activemq.artemis.jdbc.store.file;
+
+import javax.sql.DataSource;
+import java.sql.Connection;
+import java.sql.SQLException;
+
+import org.apache.activemq.artemis.jdbc.store.sql.SQLProvider;
+
+@SuppressWarnings("SynchronizeOnNonFinalField")
+public final class Db2SequentialFileDriver extends JDBCSequentialFileFactoryDriver {
+
+   public Db2SequentialFileDriver() {
+      super();
+   }
+
+   public Db2SequentialFileDriver(DataSource dataSource, SQLProvider provider) {
+      super(dataSource, provider);
+   }
+
+   public Db2SequentialFileDriver(Connection connection, SQLProvider provider) {
+      super(connection, provider);
+   }
+
+   @Override
+   protected void prepareStatements() throws SQLException {
+      this.deleteFile = connection.prepareStatement(sqlProvider.getDeleteFileSQL());
+      this.createFile = connection.prepareStatement(sqlProvider.getInsertFileSQL(), new String[]{"ID"});
+      this.selectFileByFileName = connection.prepareStatement(sqlProvider.getSelectFileByFileName());
+      this.copyFileRecord = connection.prepareStatement(sqlProvider.getCopyFileRecordByIdSQL());
+      this.renameFile = connection.prepareStatement(sqlProvider.getUpdateFileNameByIdSQL());
+      this.readLargeObject = connection.prepareStatement(sqlProvider.getReadLargeObjectSQL());
+      this.appendToLargeObject = connection.prepareStatement(sqlProvider.getAppendToLargeObjectSQL());
+      this.selectFileNamesByExtension = connection.prepareStatement(sqlProvider.getSelectFileNamesByExtensionSQL());
+   }
+
+   @Override
+   public int writeToFile(JDBCSequentialFile file, byte[] data) throws SQLException {
+      if (data == null || data.length == 0) {
+         return 0;
+      }
+      synchronized (connection) {
+         try {
+            connection.setAutoCommit(false);
+            int bytesWritten;
+            appendToLargeObject.setBytes(1, data);
+            appendToLargeObject.setLong(2, file.getId());
+            final int updatesFiles = appendToLargeObject.executeUpdate();
+            assert updatesFiles <= 1;
+            connection.commit();
+            if (updatesFiles == 0) {
+               bytesWritten = 0;
+            } else {
+               bytesWritten = data.length;
+            }
+            return bytesWritten;
+         } catch (SQLException e) {
+            connection.rollback();
+            throw e;
+         }
+      }
+   }
+}

artemis-jdbc-store/src/main/java/org/apache/activemq/artemis/jdbc/store/file/JDBCFileUtils.java

@@ -24,6 +24,7 @@ import java.sql.SQLException;
 import org.apache.activemq.artemis.jdbc.store.sql.PropertySQLProvider;
 import org.apache.activemq.artemis.jdbc.store.sql.SQLProvider;
 
+import static org.apache.activemq.artemis.jdbc.store.sql.PropertySQLProvider.Factory.SQLDialect.DB2;
 import static org.apache.activemq.artemis.jdbc.store.sql.PropertySQLProvider.Factory.SQLDialect.POSTGRESQL;
 
 class JDBCFileUtils {
@@ -32,8 +33,11 @@ class JDBCFileUtils {
                                                           String jdbcConnectionUrl,
                                                           SQLProvider provider) throws SQLException {
       final JDBCSequentialFileFactoryDriver dbDriver;
-      if (POSTGRESQL.equals(PropertySQLProvider.Factory.identifyDialect(driverClass))) {
+      final PropertySQLProvider.Factory.SQLDialect sqlDialect = PropertySQLProvider.Factory.identifyDialect(driverClass);
+      if (POSTGRESQL.equals(sqlDialect)) {
          dbDriver = new PostgresSequentialSequentialFileDriver();
+      } else if (DB2.equals(sqlDialect)) {
+         dbDriver = new Db2SequentialFileDriver();
       } else {
          dbDriver = new JDBCSequentialFileFactoryDriver();
       }
@@ -51,6 +55,8 @@ class JDBCFileUtils {
       }
       if (POSTGRESQL.equals(sqlDialect)) {
          dbDriver = new PostgresSequentialSequentialFileDriver(dataSource, provider);
+      } else if (DB2.equals(sqlDialect)) {
+         dbDriver = new Db2SequentialFileDriver(dataSource, provider);
       } else {
          dbDriver = new JDBCSequentialFileFactoryDriver(dataSource, provider);
       }
@@ -59,9 +65,12 @@ class JDBCFileUtils {
 
    static JDBCSequentialFileFactoryDriver getDBFileDriver(Connection connection, SQLProvider provider) throws SQLException {
       JDBCSequentialFileFactoryDriver dbDriver;
-      if (POSTGRESQL.equals(PropertySQLProvider.Factory.investigateDialect(connection))) {
+      final PropertySQLProvider.Factory.SQLDialect sqlDialect = PropertySQLProvider.Factory.investigateDialect(connection);
+      if (POSTGRESQL.equals(sqlDialect)) {
          dbDriver = new PostgresSequentialSequentialFileDriver(connection, provider);
          dbDriver.setConnection(connection);
+      } else if (DB2.equals(sqlDialect)) {
+         dbDriver = new Db2SequentialFileDriver(connection, provider);
       } else {
          dbDriver = new JDBCSequentialFileFactoryDriver(connection, provider);
       }

artemis-jdbc-store/src/main/java/org/apache/activemq/artemis/jdbc/store/sql/PropertySQLProvider.java

@@ -374,7 +374,7 @@ public class PropertySQLProvider implements SQLProvider {
             if (dialect == null) {
                logger.warnf("Unable to detect database dialect from connection metadata or JDBC driver name.");
             } else {
-               logger.debugf("Detect database dialect as '%s'.");
+               logger.debugf("Detect database dialect as '%s'.", dialect);
             }
          } catch (Exception e) {
             logger.debug("Unable to read JDBC metadata.", e);

artemis-jdbc-store/src/main/resources/journal-sql.properties

@@ -86,4 +86,6 @@ max-blob-size.oracle=4294967296
 table-names-case.oracle=upper
 
 # DB2 SQL statements
-create-file-table.db2=CREATE TABLE %s (ID BIGINT GENERATED ALWAYS AS IDENTITY (START WITH 1 INCREMENT BY 1), FILENAME VARCHAR(255), EXTENSION VARCHAR(10), DATA BLOB, PRIMARY KEY(ID))
+max-blob-size.db2=2147483647
+create-file-table.db2=CREATE TABLE %s (ID BIGINT GENERATED ALWAYS AS IDENTITY (START WITH 1 INCREMENT BY 1), FILENAME VARCHAR(255), EXTENSION VARCHAR(10), DATA BLOB(2G), PRIMARY KEY(ID))
+append-to-file.db2=UPDATE %s SET DATA = (DATA || ?) WHERE ID=?