content: /*
   * Copyright (C) 2006 The Android Open Source Project
   *
   * 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 android.view;
  
  import android.os.Parcel;
  import android.os.Parcelable;
  
  /**
   * A {@link Parcelable} implementation that should be used by inheritance
   * hierarchies to ensure the state of all classes along the chain is saved.
   */
  public abstract class AbsSavedState implements Parcelable {
      public static final AbsSavedState EMPTY_STATE = new AbsSavedState() {};
  
      private final Parcelable mSuperState;
  
      /**
       * Constructor used to make the EMPTY_STATE singleton
       */
      private AbsSavedState() {
          mSuperState = null;
      }
  
      /**
       * Constructor called by derived classes when creating their SavedState objects
       *
       * @param superState The state of the superclass of this view
       */
      protected AbsSavedState(Parcelable superState) {
          if (superState == null) {
              throw new IllegalArgumentException("superState must not be null");
          }
          mSuperState = superState != EMPTY_STATE ? superState : null;
      }
  
      /**
       * Constructor used when reading from a parcel. Reads the state of the superclass.
       *
       * @param source parcel to read from
       */
      protected AbsSavedState(Parcel source) {
          this(source, null);
      }
  
      /**
       * Constructor used when reading from a parcel using a given class loader.
       * Reads the state of the superclass.
       *
       * @param source parcel to read from
       * @param loader ClassLoader to use for reading
       */
      protected AbsSavedState(Parcel source, ClassLoader loader) {
          Parcelable superState = source.readParcelable(loader);
          mSuperState = superState != null ? superState : EMPTY_STATE;
      }
  
      final public Parcelable getSuperState() {
          return mSuperState;
      }
  
      public int describeContents() {
          return 0;
      }
  
      public void writeToParcel(Parcel dest, int flags) {
          dest.writeParcelable(mSuperState, flags);
      }
  
      public static final @android.annotation.NonNull Parcelable.Creator<AbsSavedState> CREATOR
              = new Parcelable.ClassLoaderCreator<AbsSavedState>() {
  
          @Override
          public AbsSavedState createFromParcel(Parcel in) {
              return createFromParcel(in, null);
          }
  
          @Override
          public AbsSavedState createFromParcel(Parcel in, ClassLoader loader) {
              Parcelable superState = in.readParcelable(loader);
              if (superState != null) {
                  throw new IllegalStateException("superState must be null");
              }
              return EMPTY_STATE;
          }
  
          @Override
          public AbsSavedState[] newArray(int size) {
              return new AbsSavedState[size];
          }
      };
  }
  