Class Pair

lib/java/src/main/java/com/dianping/cat/util/Pair.java:21–114

package com.dianping.cat.util;

public class Pair<K, V> implements Tuple {
    private volatile K key;
    private volatile V value;

    public Pair(K key, V value) {
        this.key = key;
        this.value = value;
    }

    public static <K, V> Pair<K, V> from(K key, V value) {
        return new Pair<K, V>(key, value);
    }

    @Override
    @SuppressWarnings("unchecked")
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }

        if (obj instanceof Pair) {
            Pair<Object, Object> o = (Pair<Object, Object>) obj;

            if (key == null) {
                if (o.key != null) {
                    return false;
                }
            } else if (!key.equals(o.key)) {
                return false;
            }

            if (value == null) {
                if (o.value != null) {
                    return false;
                }
            } else if (!value.equals(o.value)) {
                return false;
            }

            return true;
        }

        return false;
    }

    @Override
    @SuppressWarnings("unchecked")
    public <T> T get(int index) {
        switch (index) {
            case 0:
                return (T) key;
            case 1:
                return (T) value;
            default:
                throw new IndexOutOfBoundsException(String.format("Index from 0 to %s, but was %s!", size(), index));
        }
    }