Merge "AccessibilityNodeIdManager should hold onto weak references of Views." into qt-dev

package android.view.accessibility;

import android.util.SparseArray;

import android.view.View;

/** @hide */

public final class AccessibilityNodeIdManager {

    private SparseArray<View> mIdsToViews = new SparseArray<>();

    private WeakSparseArray<View> mIdsToViews = new WeakSparseArray<View>();

    private static AccessibilityNodeIdManager sIdManager;

    /**

/*

 * Copyright (C) 2019 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.accessibility;

import android.util.SparseArray;

import java.lang.ref.Reference;

import java.lang.ref.ReferenceQueue;

import java.lang.ref.WeakReference;

final class WeakSparseArray<E> {

    private final ReferenceQueue<E> mRefQueue = new ReferenceQueue<>();

    private final SparseArray<WeakReferenceWithId<E>> mSparseArray = new SparseArray<>();

    public void append(int key, E value) {

        removeUnreachableValues();

        mSparseArray.append(key, new WeakReferenceWithId(value, mRefQueue, key));

    }

    public void remove(int key) {

        removeUnreachableValues();

        mSparseArray.remove(key);

    }

    public E get(int key) {

        removeUnreachableValues();

        WeakReferenceWithId<E> ref = mSparseArray.get(key);

        return ref != null ? ref.get() : null;

    }

    private void removeUnreachableValues() {

        for (Reference ref = mRefQueue.poll(); ref != null; ref = mRefQueue.poll()) {

            mSparseArray.remove(((WeakReferenceWithId) ref).mId);

        }

    }

    private static class WeakReferenceWithId<E> extends WeakReference<E> {

        final int mId;

        WeakReferenceWithId(E referent, ReferenceQueue<? super E> q, int id) {

            super(referent, q);

            mId = id;

        }

    }

}