Java tutorial
//package com.java2s; import java.util.LinkedHashMap; import java.util.Map; public class Main { @SafeVarargs public static <K, V> Map<K, V> merge(Map<K, V>... maps) { if (maps == null) { return null; } Map<K, V> result = null; for (Map<K, V> map : maps) { if (map != null) { if (result == null) { result = new LinkedHashMap<K, V>(); } result.putAll(map); } } return result; } }