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    package org.apache.hadoop.lib.wsrs;
019    
020    import org.apache.hadoop.classification.InterfaceAudience;
021    
022    import com.google.common.collect.Lists;
023    
024    import java.util.List;
025    import java.util.Map;
026    
027    /**
028     * Class that contains all parsed JAX-RS parameters.
029     * <p/>
030     * Instances are created by the {@link ParametersProvider} class.
031     */
032    @InterfaceAudience.Private
033    public class Parameters {
034      private Map<String, List<Param<?>>> params;
035    
036      /**
037       * Constructor that receives the request parsed parameters.
038       *
039       * @param params the request parsed parameters.
040       */
041      public Parameters(Map<String, List<Param<?>>> params) {
042        this.params = params;
043      }
044    
045      /**
046       * Returns the value of a request parsed parameter.
047       *
048       * @param name parameter name.
049       * @param klass class of the parameter, used for value casting.
050       * @return the value of the parameter.
051       */
052      @SuppressWarnings("unchecked")
053      public <V, T extends Param<V>> V get(String name, Class<T> klass) {
054        List<Param<?>> multiParams = (List<Param<?>>)params.get(name);
055        if (multiParams != null && multiParams.size() > 0) {
056          return ((T) multiParams.get(0)).value(); // Return first value;
057        }
058        return null;
059      }
060      
061      /**
062       * Returns the values of a request parsed parameter.
063       *
064       * @param name parameter name.
065       * @param klass class of the parameter, used for value casting.
066       * @return List<V> the values of the parameter.
067       */
068      @SuppressWarnings("unchecked")
069      public <V, T extends Param<V>> List<V> getValues(String name, Class<T> klass) {
070        List<Param<?>> multiParams = (List<Param<?>>)params.get(name);
071        List<V> values = Lists.newArrayList();
072        if (multiParams != null) {
073          for (Param<?> param : multiParams) {
074            V value = ((T) param).value();
075            if (value != null) {
076              values.add(value);
077            }
078          }
079        }
080        return values;
081      }
082    }