| /* |
| * Copyright (C) 2018 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.util.imagepool; |
| |
| import com.android.tools.layoutlib.annotations.Nullable; |
| |
| import android.util.imagepool.Bucket.BucketCreationMetaData; |
| import android.util.imagepool.ImagePool.Image.Orientation; |
| import android.util.imagepool.ImagePool.ImagePoolPolicy; |
| |
| import java.awt.image.BufferedImage; |
| import java.util.Map; |
| |
| /* private package */ class ImagePoolHelper { |
| |
| @Nullable |
| public static BucketCreationMetaData getBucketCreationMetaData(int w, int h, int type, ImagePoolPolicy poolPolicy, ImagePoolStats stats) { |
| // Find the bucket sizes for both dimensions |
| int widthBucket = -1; |
| int heightBucket = -1; |
| int index = 0; |
| |
| for (int bucketMinSize : poolPolicy.mBucketSizes) { |
| if (widthBucket == -1 && w <= bucketMinSize) { |
| widthBucket = bucketMinSize; |
| |
| if (heightBucket != -1) { |
| break; |
| } |
| } |
| if (heightBucket == -1 && h <= bucketMinSize) { |
| heightBucket = bucketMinSize; |
| |
| if (widthBucket != -1) { |
| break; |
| } |
| } |
| ++index; |
| } |
| |
| stats.recordBucketRequest(w, h); |
| |
| if (index >= poolPolicy.mNumberOfCopies.length) { |
| return null; |
| } |
| |
| // TODO: Apply orientation |
| // if (widthBucket < heightBucket) { |
| // return new BucketCreationMetaData(heightBucket, widthBucket, type, poolPolicy.mNumberOfCopies[index], |
| // Orientation.CW_90, poolPolicy.mBucketMaxCacheSize); |
| // } |
| return new BucketCreationMetaData(widthBucket, heightBucket, type, poolPolicy.mNumberOfCopies[index], |
| Orientation.NONE, poolPolicy.mBucketMaxCacheSize); |
| } |
| |
| @Nullable |
| public static BufferedImage getBufferedImage( |
| Bucket bucket, BucketCreationMetaData metaData, ImagePoolStats stats) { |
| |
| // strongref is just for gc. |
| BufferedImage strongRef = populateBucket(bucket, metaData, stats); |
| |
| // pool is too small to create the requested buffer. |
| if (bucket.isEmpty()) { |
| assert strongRef == null; |
| return null; |
| } |
| |
| // Go through the bucket of soft references to find the first buffer that's not null. |
| // Even if gc is triggered here, strongref should survive. |
| BufferedImage img = bucket.remove(); |
| while (img == null && !bucket.isEmpty()) { |
| img = bucket.remove(); |
| } |
| |
| if (img == null && bucket.isEmpty()) { |
| // Whole buffer was null. Recurse. |
| return getBufferedImage(bucket, metaData, stats); |
| } |
| return img; |
| } |
| |
| /** |
| * Populate the bucket in greedy manner to avoid fragmentation. |
| * Behaviour is controlled by {@link ImagePoolPolicy}. |
| * Returns one strong referenced buffer to avoid getting results gc'd. Null if pool is not large |
| * enough. |
| */ |
| @Nullable |
| private static BufferedImage populateBucket( |
| Bucket bucket, BucketCreationMetaData metaData, ImagePoolStats stats) { |
| if (!bucket.isEmpty()) { |
| // If not empty no need to populate. |
| return null; |
| } |
| |
| BufferedImage strongRef = null; |
| for (int i = 0; i < metaData.mNumberOfCopies; i++) { |
| if (!stats.fitsMaxCacheSize( |
| metaData.mWidth, metaData.mHeight, metaData.mMaxCacheSize)) { |
| break; |
| } |
| strongRef =new BufferedImage(metaData.mWidth, metaData.mHeight, |
| metaData.mType); |
| bucket.offer(strongRef); |
| stats.recordBucketCreation(metaData.mWidth, metaData.mHeight); |
| } |
| return strongRef; |
| } |
| |
| private static String toKey(int w, int h, int type) { |
| return new StringBuilder() |
| .append(w) |
| .append('x') |
| .append(h) |
| .append(':') |
| .append(type) |
| .toString(); |
| } |
| |
| public static Bucket getBucket(Map<String, Bucket> map, BucketCreationMetaData metaData, ImagePoolPolicy mPolicy) { |
| String key = toKey(metaData.mWidth, metaData.mHeight, metaData.mType); |
| Bucket bucket = map.get(key); |
| if (bucket == null) { |
| bucket = new Bucket(); |
| map.put(key, bucket); |
| } |
| return bucket; |
| } |
| } |