content: /**
   * Copyright (C) 2007 The Guava Authors
   *
   * 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.fernandocejas.arrow.collections;
  
  import static com.fernandocejas.arrow.checks.Preconditions.checkState;
  
  /**
   * Precondition checks useful in collection implementations.
   */
  public final class CollectPreconditions {
  
    public static void checkIndexNonnegative(int value) {
      if (value < 0) {
        throw new IndexOutOfBoundsException("value (" + value
            + ") must not be negative");
      }
    }
  
    public static int checkNonnegative(int value, String name) {
      if (value < 0) {
        throw new IllegalArgumentException(name + " cannot be negative but was: " + value);
      }
      return value;
    }
  
    /**
     * Precondition tester for {@code Iterator.remove()} that throws an exception with a consistent
     * error message.
     */
    static void checkRemove(boolean canRemove) {
      checkState(canRemove, "no calls to next() since the last call to remove()");
    }
  
    public static Object[] checkElementsNotNull(Object... array) {
      return checkElementsNotNull(array, array.length);
    }
  
    public static Object[] checkElementsNotNull(Object[] array, int length) {
      for (int i = 0; i < length; i++) {
        checkElementNotNull(array[i], i);
      }
      return array;
    }
  
    // We do this instead of Preconditions.checkNotNull to save boxing and array
    // creation cost.
    public static Object checkElementNotNull(Object element, int index) {
      if (element == null) {
        throw new NullPointerException("at index " + index);
      }
      return element;
    }
  
    private CollectPreconditions() {
      // no instances
    }
  }
  