/*
 * Copyright (C) 2015 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.callbuilder.util;

/**
 * Utility code for checking preconditions of methods and constructors.
 */
public class Preconditions {
  /**
   * Checks if the given value is {@code null}.
   *
   * @throws NullPointerException if {@code value} is {@code null}
   * @return the {@code value} argument unchanged
   */
  public static <T> T checkNotNull(T value) {
    if (value == null) {
      throw new NullPointerException();
    }

    return value;
  }

  private Preconditions() {}
}