| /** |
| * 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.sqoop.mapreduce.db; |
| |
| import java.io.IOException; |
| import java.sql.Connection; |
| import java.sql.SQLException; |
| |
| import org.apache.hadoop.conf.Configuration; |
| |
| /** |
| * Base class for handling SQL failures to while executing operations on the |
| * target database. |
| * Subclasses can provide different handling for connection errors like |
| * recovering from connection resets, or handling server throttling |
| */ |
| public abstract class SQLFailureHandler { |
| |
| // Job configuration for the currently running job |
| protected Configuration conf; |
| |
| /** |
| * Initialize the the handler with job configuration. |
| */ |
| public void initialize(Configuration c) throws IOException { |
| this.conf = c; |
| } |
| |
| /** |
| * Check whether the given failure is supported by the connection failure |
| * handler. |
| */ |
| public abstract boolean canHandleFailure(Throwable failureCause); |
| |
| /** |
| * Provide specific handling for the connection failure and return a new |
| * valid connection. |
| */ |
| public abstract Connection recover() throws IOException; |
| |
| /** |
| * Establish a connection to the target database. |
| */ |
| protected Connection getConnection() |
| throws ClassNotFoundException, SQLException { |
| // Get a DBConfiguration object from the current job configuration |
| DBConfiguration dbConf = new DBConfiguration(conf); |
| Connection conn = null; |
| conn = dbConf.getConnection(); |
| return conn; |
| } |
| } |