Java Map Add addOne(Map map, T key)

Description

given a map of ?

License

Apache License

Parameter

Parameter	Description
T	a parameter
map	a parameter
key	a parameter

Declaration

public static <T> void addOne(Map<T, Integer> map, T key) 

Method Source Code

//package com.java2s;
/*//  w  w w  .  j av  a  2s. c om
Copyright 2008 Flaptor (flaptor.com) 
    
Licensed 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.
*/

import java.util.Map;

public class Main {
    /**
     * given a map of ? -> Integer counting occurrences, this adds one to the occurrence
     * @param <T>
     * @param map
     * @param key
     */
    public static <T> void addOne(Map<T, Integer> map, T key) {
        Integer count = map.get(key);
        if (count == null)
            count = 0;
        map.put(key, count + 1);
    }
}

Related

1. addOne(Map map, K key)
2. addTo(Map> map, K key, T value)
3. addTo(Map map, N key, E element, Class collectionClass)
4. addToAnd(T target, Map... items)
5. addToList(Map> map, X key, Y value)