/*
 * Copyright 2008 Google 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.google.gwt.dev.util;

/**
 * @param <L>
 * @param <R>
 */
public class Pair<L, R> {
  public static <L, R> Pair<L, R> create(L l, R r) {
    return new Pair<L, R>(l, r);
  }
  
  public final L left;
  public final R right;
  
  private Pair(L left, R right) {
    this.left = left;
    this.right = right;
  }

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

  public L getLeft() {
    return left;
  }

  public R getRight() {
    return right;
  }

  @Override
  public int hashCode() {
    final int prime = 31;
    int result = 1;
    result = prime * result + ((left == null) ? 0 : left.hashCode());
    result = prime * result + ((right == null) ? 0 : right.hashCode());
    return result;
  }
  
  @Override
  public String toString() {
    return "(" + left + "," + right + ")";
  }
}