Pair.java

/*
 * Copyright (C) 2016 The Android Open Source Project
 *
 * 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.android.apksig.internal.util;

/**
 * Pair of two elements.
 */
public final class Pair<A, B> {
    private final A mFirst;
    private final B mSecond;

    private Pair(A first, B second) {
        mFirst = first;
        mSecond = second;
    }

    public static <A, B> Pair<A, B> of(A first, B second) {
        return new Pair<A, B>(first, second);
    }

    public A getFirst() {
        return mFirst;
    }

    public B getSecond() {
        return mSecond;
    }

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + ((mFirst == null) ? 0 : mFirst.hashCode());
        result = prime * result + ((mSecond == null) ? 0 : mSecond.hashCode());
        return result;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        @SuppressWarnings("rawtypes")
        Pair other = (Pair) obj;
        if (mFirst == null) {
            if (other.mFirst != null) {
                return false;
            }
        } else if (!mFirst.equals(other.mFirst)) {
            return false;
        }
        if (mSecond == null) {
            if (other.mSecond != null) {
                return false;
            }
        } else if (!mSecond.equals(other.mSecond)) {
            return false;
        }
        return true;
    }
}