Pair.java

package example.utils;

import org.apache.commons.lang.builder.EqualsBuilder;
import org.apache.commons.lang.builder.HashCodeBuilder;

public class Pair<K, V> {

    private final K key;
    private final V value;

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

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

    public K getKey() {
        return key;
    }

    public V getValue() {
        return value;
    }

    @Override
    public boolean equals(Object obj) {
        if (obj == this) {
            return true;
        }
        if (obj instanceof Pair) {
            Pair other = (Pair) obj;
            return new EqualsBuilder()
                    .append(this.getKey(), other.getKey())
                    .append(this.getValue(), other.getValue())
                    .isEquals();
        }
        return false;
    }

    @Override
    public int hashCode() {
        return new HashCodeBuilder().append(key).append(value).toHashCode();
    }

    @Override
    public String toString() {
        return Strings.toString(this);
    }
}