// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc.  All rights reserved.
// http://code.google.com/p/protobuf/
//
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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();

}