network/util/MapConfigProvider.java

0001 /*
0002  * Licensed to the Apache Software Foundation (ASF) under one or more
0003  * contributor license agreements.  See the NOTICE file distributed with
0004  * this work for additional information regarding copyright ownership.
0005  * The ASF licenses this file to You under the Apache License, Version 2.0
0006  * (the "License"); you may not use this file except in compliance with
0007  * the License.  You may obtain a copy of the License at
0008  *
0009  *    http://www.apache.org/licenses/LICENSE-2.0
0010  *
0011  * Unless required by applicable law or agreed to in writing, software
0012  * distributed under the License is distributed on an "AS IS" BASIS,
0013  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
0014  * See the License for the specific language governing permissions and
0015  * limitations under the License.
0016  */
0017
0018 package org.apache.spark.network.util;
0019
0020 import java.util.Collections;
0021 import java.util.HashMap;
0022 import java.util.Map;
0023 import java.util.NoSuchElementException;
0024
0025 /** ConfigProvider based on a Map (copied in the constructor). */
0026 public class MapConfigProvider extends ConfigProvider {
0027
0028   public static final MapConfigProvider EMPTY = new MapConfigProvider(Collections.emptyMap());
0029
0030   private final Map<String, String> config;
0031
0032   public MapConfigProvider(Map<String, String> config) {
0033     this.config = new HashMap<>(config);
0034   }
0035
0036   @Override
0037   public String get(String name) {
0038     String value = config.get(name);
0039     if (value == null) {
0040       throw new NoSuchElementException(name);
0041     }
0042     return value;
0043   }
0044
0045   @Override
0046   public String get(String name, String defaultValue) {
0047     String value = config.get(name);
0048     return value == null ? defaultValue : value;
0049   }
0050
0051   @Override
0052   public Iterable<Map.Entry<String, String>> getAll() {
0053     return config.entrySet();
0054   }
0055
0056 }