# Pair.java

    /*
     * Copyright 2011, 2012 Odysseus Software GmbH
     *
     * 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.
     */
    package org.apache.synapse.commons.staxon.core.base;

    /**
     * Object pair.
     *
     * @param <F> first type
     * @param <S> second type
     */
    class Pair<F, S> {
        private final F first;
        private final S second;

        /**
         * Create a new pair instance.
         *
         * @param first  first object
         * @param second second object
         */
        Pair(F first, S second) {
            this.first = first;
            this.second = second;
        }

        /**
         * @return first object
         */
        F getFirst() {
            return first;
        }

        /**
         * @return second object
         */
        S getSecond() {
            return second;
        }

        @Override
        public int hashCode() {
            return (first == null ? 0 : first.hashCode()) ^ (second == null ? 0 : second.hashCode());
        }

        @Override
        public boolean equals(Object obj) {
            if (this == obj) {
                return true;
            }
            if (obj == null || getClass() != obj.getClass()) {
                return false;
            }
            Pair<?, ?> other = (Pair<?, ?>) obj;
            if (first == null) {
                if (other.first != null) {
                    return false;
                }
            } else if (!first.equals(other.first)) {
                return false;
            }
            if (second == null) {
                if (other.second != null) {
                    return false;
                }
            } else if (!second.equals(other.second)) {
                return false;
            }
            return true;
        }

        @Override
        public String toString() {
            return "Pair(" + first + "," + second + ")";
        }
    }