// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc.  All rights reserved.
// https://developers.google.com/protocol-buffers/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

package com.google.protobuf;

/**
 * Base interface for methods common to {@link MessageLite}
 * and {@link MessageLite.Builder} to provide type equivalency.
 *
 * @author jonp@google.com (Jon Perlow)
 */
public interface MessageLiteOrBuilder {
  /**
   * Get an instance of the type with no fields set. Because no fields are set,
   * all getters for singular fields will return default values and repeated
   * fields will appear empty.
   * This may or may not be a singleton.  This differs from the
   * {@code getDefaultInstance()} method of generated message classes in that
   * this method is an abstract method of the {@code MessageLite} interface
   * whereas {@code getDefaultInstance()} is a static method of a specific
   * class.  They return the same thing.
   */
  MessageLite getDefaultInstanceForType();

  /**
   * Returns true if all required fields in the message and all embedded
   * messages are set, false otherwise.
   *
   * <p>See also: {@link MessageOrBuilder#getInitializationErrorString()}
   */
  boolean isInitialized();

}
