/*
* 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.
*/
This package contains implementations of the Map, IterableMap, OrderedMap and SortedMap interfaces. A Map provides a lookup from a key to a value. A number of implementations also support the new MapIterator interface that enables simple iteration of map keys and values.
The following implementations are provided:
- CaseInsensitiveMap - map that compares keys in a case insensitive way
- CompositeMap - map that combines multiple maps into a single view
- HashedMap - general purpose HashMap replacement supporting MapIterator
- Flat3Map - designed for good performance at size 3 or less
- LinkedMap - a hash map that maintains insertion order, supporting OrderedMapIterator
- LRUMap - a hash map that maintains a maximum size by removing the least recently used entries
- MultiKeyMap - map that provides special methods for using more than one key to access the value
- ReferenceMap - allows the garbage collector to collect keys and values using equals() for comparison
- ReferenceIdentityMap - allows the garbage collector to collect keys and values using == for comparison
- SingletonMap - a fully featured map to hold one key-value pair
- StaticBucketMap - internally synchronized and designed for thread-contentious environments
The following decorators are provided:
- Unmodifiable - ensures the collection cannot be altered
- Predicated - ensures that only elements that are valid according to a predicate can be added
- Transformed - transforms each element added
- FixedSize - ensures that the size of the map cannot change
- Defaulted - provides default values for non-existing keys
- Lazy - creates objects in the map on demand
- ListOrdered - ensures that insertion order is retained
/**
* This package contains implementations of the {@link java.util.Map Map},
* {@link org.apache.commons.collections4.IterableMap IterableMap},
* {@link org.apache.commons.collections4.OrderedMap OrderedMap} and
* {@link java.util.SortedMap SortedMap} interfaces.
* A Map provides a lookup from a key to a value.
* A number of implementations also support the new MapIterator interface that enables
* simple iteration of map keys and values.
* <p>
* The following implementations are provided:
* <ul>
* <li>CaseInsensitiveMap - map that compares keys in a case insensitive way
* <li>CompositeMap - map that combines multiple maps into a single view
* <li>HashedMap - general purpose HashMap replacement supporting MapIterator
* <li>Flat3Map - designed for good performance at size 3 or less
* <li>LinkedMap - a hash map that maintains insertion order, supporting OrderedMapIterator
* <li>LRUMap - a hash map that maintains a maximum size by removing the least recently used entries
* <li>MultiKeyMap - map that provides special methods for using more than one key to access the value
* <li>ReferenceMap - allows the garbage collector to collect keys and values using equals() for comparison
* <li>ReferenceIdentityMap - allows the garbage collector to collect keys and values using == for comparison
* <li>SingletonMap - a fully featured map to hold one key-value pair
* <li>StaticBucketMap - internally synchronized and designed for thread-contentious environments
* </ul>
* <p>
* The following decorators are provided:
* <ul>
* <li>Unmodifiable - ensures the collection cannot be altered
* <li>Predicated - ensures that only elements that are valid according to a predicate can be added
* <li>Transformed - transforms each element added
* <li>FixedSize - ensures that the size of the map cannot change
* <li>Defaulted - provides default values for non-existing keys
* <li>Lazy - creates objects in the map on demand
* <li>ListOrdered - ensures that insertion order is retained
* </ul>
*
*/
package org.apache.commons.collections4.map;