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Java Simplified. Extensions and Useful Constructs for the Java Platform. Codeprimate Elements (a.k.a. cp-elements) is a Java library and micro-framework used to simplify the development of software applications written in Java. Elements packages several APIs into one library in order to address various application concerns and aspects of software design and development collectively and conveniently. Elements is a highly simple, yet robust and proven library built on solid OO principles, software design patterns and best practices to effectively solve common and reoccurring problems in software development.

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/*
 * Copyright 2016 Author or 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 org.cp.elements.util.stream;

import java.util.Arrays;
import java.util.Collection;
import java.util.stream.Stream;
import java.util.stream.StreamSupport;

import org.cp.elements.lang.Assert;

/**
 * The {@link StreamUtils} class is a collection of utility methods for working with Java 8 {@link Stream Streams}.
 *
 * @author John J. Blum
 * @see java.util.Arrays
 * @see java.util.stream.Stream
 * @see java.util.stream.StreamSupport
 * @see org.cp.elements.util.CollectionUtils
 * @since 1.0.0
 */
@SuppressWarnings("unused")
public abstract class StreamUtils {

  /**
   * Returns a {@link Stream} from the array of elements.
   *
   * @param  Class type of the elements in the array.
   * @param elements array of elements to convert into a {@link Stream}.
   * @return a {@link Stream} for the elements in the array.
   * @see java.util.stream.Stream
   */
  @SafeVarargs
  public static  Stream stream(T... elements) {
    return Arrays.stream(elements);
  }

  /**
   * Returns a {@link Stream} from the {@link Iterable} collection of elements.
   *
   * @param  Class type of the elements in the {@link Iterable}.
   * @param iterable {@link Iterable} collection of elements to convert into a {@link Stream}.
   * @return a {@link Stream} for the elements in the {@link Iterable}.
   * @throws IllegalArgumentException if {@link Iterable} is null.
   * @see java.util.stream.Stream
   * @see java.lang.Iterable
   */
  @SuppressWarnings("unchecked")
  public static  Stream stream(Iterable iterable) {
    Assert.notNull(iterable, "Iterable cannot be null");

    return (iterable instanceof Collection ? ((Collection) iterable).stream()
      : StreamSupport.stream(iterable.spliterator(), false));
  }
}