Java tutorial
//package com.java2s; import java.util.Map; public class Main { /** * @param <T> * @param aMap * @param aKey * @return New Count Value */ public static <T> int incrementCount(Map<T, Integer> aMap, T aKey) { return incrementCount(aMap, aKey, 1); } /** * @param <T> * @param aMap * @param aKey * @param aCount * @return New Count Value */ public static <T> int incrementCount(Map<T, Integer> aMap, T aKey, Integer aCount) { Integer count = aMap.get(aKey); if (count == null) { count = 0; } int newCount = count + aCount; aMap.put(aKey, newCount); return newCount; } }