org.apache.hadoop.hive.ql.DriverFactory.java Source code

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Here is the source code for org.apache.hadoop.hive.ql.DriverFactory.java

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/*
 * 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.hadoop.hive.ql;

import java.util.ArrayList;

import org.apache.hadoop.hive.conf.HiveConf;
import org.apache.hadoop.hive.conf.HiveConf.ConfVars;
import org.apache.hadoop.hive.ql.reexec.IReExecutionPlugin;
import org.apache.hadoop.hive.ql.reexec.ReExecDriver;
import org.apache.hadoop.hive.ql.reexec.ReExecutionOverlayPlugin;
import org.apache.hadoop.hive.ql.reexec.ReOptimizePlugin;

import com.google.common.base.Strings;

/**
 * Constructs a driver for ql clients.
 */
public class DriverFactory {

    public static IDriver newDriver(HiveConf conf) {
        return newDriver(getNewQueryState(conf), null, null);
    }

    public static IDriver newDriver(QueryState queryState, String userName, QueryInfo queryInfo) {
        boolean enabled = queryState.getConf().getBoolVar(ConfVars.HIVE_QUERY_REEXECUTION_ENABLED);
        if (!enabled) {
            return new Driver(queryState, userName, queryInfo);
        }

        String strategies = queryState.getConf().getVar(ConfVars.HIVE_QUERY_REEXECUTION_STRATEGIES);
        strategies = Strings.nullToEmpty(strategies).trim().toLowerCase();
        ArrayList<IReExecutionPlugin> plugins = new ArrayList<>();
        for (String string : strategies.split(",")) {
            if (string.trim().isEmpty()) {
                continue;
            }
            plugins.add(buildReExecPlugin(string));
        }

        return new ReExecDriver(queryState, userName, queryInfo, plugins);
    }

    private static IReExecutionPlugin buildReExecPlugin(String name) throws RuntimeException {
        if (name.equals("overlay")) {
            return new ReExecutionOverlayPlugin();
        }
        if (name.equals("reoptimize")) {
            return new ReOptimizePlugin();
        }
        throw new RuntimeException("Unknown re-execution plugin: " + name + " ("
                + ConfVars.HIVE_QUERY_REEXECUTION_STRATEGIES.varname + ")");
    }

    private static QueryState getNewQueryState(HiveConf conf) {
        return new QueryState.Builder().withGenerateNewQueryId(true).withHiveConf(conf).build();
    }
}