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      1 /*
      2  * Copyright (C) 2016 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 package com.android.car.apps.common;
     17 
     18 import android.graphics.Bitmap;
     19 import android.util.Log;
     20 import android.util.SparseArray;
     21 
     22 import java.lang.ref.SoftReference;
     23 import java.lang.reflect.InvocationTargetException;
     24 import java.lang.reflect.Method;
     25 import java.util.ArrayList;
     26 
     27 
     28 /**
     29  * This class saves recycle bitmap as SoftReference,  which is too vulnerable to
     30  * be garbage collected due to other part of application is re-allocating lots of
     31  * memory,  we will lose all SoftReference in a GC run.  We should maintain
     32  * certain amount of recycled bitmaps in memory, we may also need remove bitmap from LRUCache
     33  * if we are not able to get a recycled bitmap here.
     34  *
     35  * @hide
     36  */
     37 public class RecycleBitmapPool {
     38 
     39     private static final String TAG = "RecycleBitmapPool";
     40     private static final boolean DEBUG = false;
     41     // allow reuse bitmap with larger bytes, set to 0 to disable different byte size
     42     private static final int LARGER_BITMAP_ALLOWED_REUSE = 0;
     43     private static final boolean LARGER_BITMAP_ALLOWED = LARGER_BITMAP_ALLOWED_REUSE > 0;
     44 
     45     private static Method sGetAllocationByteCount;
     46 
     47     static {
     48         try {
     49             // KLP or later
     50             sGetAllocationByteCount = Bitmap.class.getMethod("getAllocationByteCount");
     51         } catch (NoSuchMethodException e) {
     52         }
     53     }
     54 
     55     private final SparseArray<ArrayList<SoftReference<Bitmap>>> mRecycled8888 =
     56             new SparseArray<ArrayList<SoftReference<Bitmap>>>();
     57 
     58     public RecycleBitmapPool() {
     59     }
     60 
     61     public static int getSize(Bitmap bitmap) {
     62         if (sGetAllocationByteCount != null) {
     63             try {
     64                 return (Integer) sGetAllocationByteCount.invoke(bitmap);
     65             } catch (IllegalArgumentException e) {
     66                 Log.e(TAG, "getAllocationByteCount() failed", e);
     67             } catch (IllegalAccessException e) {
     68                 Log.e(TAG, "getAllocationByteCount() failed", e);
     69             } catch (InvocationTargetException e) {
     70                 Log.e(TAG, "getAllocationByteCount() failed", e);
     71             }
     72             sGetAllocationByteCount = null;
     73         }
     74         return bitmap.getByteCount();
     75     }
     76 
     77     private static int getSize(int width, int height) {
     78         if (width >= 2048 || height >= 2048) {
     79             return 0;
     80         }
     81         return width * height * 4;
     82     }
     83 
     84     public void addRecycledBitmap(Bitmap bitmap) {
     85         if (bitmap.isRecycled()) {
     86             return;
     87         }
     88         Bitmap.Config config = bitmap.getConfig();
     89         if (config != Bitmap.Config.ARGB_8888) {
     90             return;
     91         }
     92         int key = getSize(bitmap);
     93         if (key == 0) {
     94             return;
     95         }
     96         synchronized (mRecycled8888) {
     97             ArrayList<SoftReference<Bitmap>> list = mRecycled8888.get(key);
     98             if (list == null) {
     99                 list = new ArrayList<SoftReference<Bitmap>>();
    100                 mRecycled8888.put(key, list);
    101             }
    102             list.add(new SoftReference<Bitmap>(bitmap));
    103             if (DEBUG) {
    104                 Log.d(TAG, list.size() + " add bitmap " + bitmap.getWidth() + " "
    105                         + bitmap.getHeight());
    106             }
    107         }
    108     }
    109 
    110     public Bitmap getRecycledBitmap(int width, int height) {
    111         int key = getSize(width, height);
    112         if (key == 0) {
    113             return null;
    114         }
    115         synchronized (mRecycled8888) {
    116             // for the new version with getAllocationByteCount(), we allow larger size
    117             // to be reused for the bitmap,  otherwise we just looks for same size
    118             Bitmap bitmap = getRecycledBitmap(mRecycled8888.get(key));
    119             if (sGetAllocationByteCount == null || bitmap != null) {
    120                 return bitmap;
    121             }
    122             if (LARGER_BITMAP_ALLOWED) {
    123                 for (int i = 0, c = mRecycled8888.size(); i < c; i++) {
    124                     int k = mRecycled8888.keyAt(i);
    125                     if (k > key && k <= key * LARGER_BITMAP_ALLOWED_REUSE) {
    126                         bitmap = getRecycledBitmap(mRecycled8888.valueAt(i));
    127                         if (bitmap != null) {
    128                             return bitmap;
    129                         }
    130                     }
    131                 }
    132             }
    133         }
    134         if (DEBUG) {
    135             Log.d(TAG, "not avaialbe for " + width + "," + height);
    136         }
    137         return null;
    138     }
    139 
    140     private static Bitmap getRecycledBitmap(ArrayList<SoftReference<Bitmap>> list) {
    141         if (list != null && !list.isEmpty()) {
    142             while (!list.isEmpty()) {
    143                 SoftReference<Bitmap> ref = list.remove(list.size() - 1);
    144                 Bitmap bitmap = ref.get();
    145                 if (bitmap != null && !bitmap.isRecycled()) {
    146                     if (DEBUG) {
    147                         Log.d(TAG, "reuse " + bitmap.getWidth() + " " + bitmap.getHeight());
    148                     }
    149                     return bitmap;
    150                 } else {
    151                     if (DEBUG) {
    152                         Log.d(TAG, " we lost SoftReference to bitmap");
    153                     }
    154                 }
    155             }
    156         }
    157         return null;
    158     }
    159 }
    160