Pair.java

/*
 * Copyright 2014, Tuplejump Inc.
 *
 * 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 com.tuplejump.stargate.utils;

import com.google.common.base.Objects;

/**
 * User: satya
 */
public class Pair<T1, T2> {
    public final T1 left;
    public final T2 right;

    protected Pair(T1 left, T2 right) {
        this.left = left;
        this.right = right;
    }

    @Override
    public final int hashCode() {
        int hashCode = 31 + (left == null ? 0 : left.hashCode());
        return 31 * hashCode + (right == null ? 0 : right.hashCode());
    }

    @Override
    public final boolean equals(Object o) {
        if (!(o instanceof Pair))
            return false;
        Pair that = (Pair) o;
        // handles nulls properly
        return Objects.equal(left, that.left) && Objects.equal(right, that.right);
    }

    @Override
    public String toString() {
        return "(" + left + "," + right + ")";
    }

    public static <X, Y> Pair<X, Y> create(X x, Y y) {
        return new Pair<X, Y>(x, y);
    }
}