Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Copyright (c) 2009 Stephan Schloepke and innoQ Deutschland GmbH
 *
 * Stephan Schloepke: http://www.schloepke.de/
 * innoQ Deutschland GmbH: http://www.innoq.com/
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

import java.util.Collections;

import java.util.LinkedHashMap;

import java.util.Map;

public class Main {
    /**
     * Join the two given maps to one by checking if one of the two maps already fulfills everything. Be aware that the
     * newly created collection is unmodifiable but will change if the underlying collections change!
     *
     * @param <K>    The key type
     * @param <V>    The value type
     * @param first  The first {@link Map} to join
     * @param second The second {@link Map} to join
     *
     * @return A {@link Map} with the joined content (can be one of the given map if the other is empty or null)
     */
    public static <K, V> Map<K, V> joinMapUnmodifiable(Map<K, V> first, Map<K, V> second) {
        if (first == null || first.isEmpty()) {
            if (second == null || second.isEmpty()) {
                return Collections.emptyMap();
            } else {
                return Collections.unmodifiableMap(second);
            }
        } else if (second == null || second.isEmpty()) {
            return Collections.unmodifiableMap(first);
        } else {
            Map<K, V> temp = new LinkedHashMap<K, V>(first.size() + second.size());
            temp.putAll(first);
            temp.putAll(second);
            return Collections.unmodifiableMap(temp);
        }
    }
}