001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *      http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018
019package org.apache.oozie.util;
020
021import org.apache.hadoop.conf.Configuration;
022import org.apache.oozie.service.ELService;
023import org.apache.oozie.service.Services;
024
025import java.util.HashMap;
026import java.util.Map;
027
028/**
029 * EL utilities
030 */
031public class ELUtils {
032
033    /**
034     * Resolves the application name using the configuration properties to resolve any EL variable.
035     *
036     * @param name name to EL resolve.
037     * @param conf configuration to use for resolving any EL variable in the name.
038     *
039     * @return the resolved application name.
040     *
041     * @throws Exception thrown if the name could not be EL resolved.
042     */
043    public static String resolveAppName(String name, Configuration conf) throws Exception {
044        ELService elService = Services.get().get(ELService.class);
045        ELEvaluator elEvaluator = elService.createEvaluator("job-submit");
046        Map<String, Object> map = new HashMap<String, Object>();
047        for (Map.Entry<String, String> entry : conf) {
048            map.put(entry.getKey(), entry.getValue());
049        }
050        elEvaluator.getContext().setVariables(map);
051        return elEvaluator.evaluate(name, String.class);
052    }
053
054}