org.apache.solr.common.util.SimpleOrderedMap Maven / Gradle / Ivy
/*
* 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.solr.common.util;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
/**
* SimpleOrderedMap is a {@link NamedList} where access by key is more important than
* maintaining order when it comes to representing the held data in other forms, as ResponseWriters
* normally do. It's normally not a good idea to repeat keys or use null keys, but this is not
* enforced. If key uniqueness enforcement is desired, use a regular {@link Map}.
*
* For example, a JSON response writer may choose to write a SimpleOrderedMap as
* {"foo":10,"bar":20} and may choose to write a NamedList as ["foo",10,"bar",20]. An XML response
* writer may choose to render both the same way.
*
*
This class does not provide efficient lookup by key, its main purpose is to hold data to be
* serialized. It aims to minimize overhead and to be efficient at adding new elements.
*/
public class SimpleOrderedMap extends NamedList {
/** Creates an empty instance */
public SimpleOrderedMap() {
super();
}
public SimpleOrderedMap(int sz) {
super(sz);
}
/**
* Creates an instance backed by an explicitly specified list of pairwise names/values.
*
* TODO: this method was formerly public, now that it's not we can change the impl details of
* this class to be based on a Map.Entry[]
*
* @param nameValuePairs underlying List which should be used to implement a SimpleOrderedMap;
* modifying this List will affect the SimpleOrderedMap.
* @lucene.internal
*/
private SimpleOrderedMap(List