Initial commit from Gmail's Cache system.

Change-Id: I14168ab3bc02b77399a1812f62bd77ac797232c5

1 files changed, 276 insertions, 0 deletions

diff --git a/src/com/android/bitmap/drawable/BasicBitmapDrawable.java b/src/com/android/bitmap/drawable/BasicBitmapDrawable.java
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+++ b/src/com/android/bitmap/drawable/BasicBitmapDrawable.java
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+/*
+ * Copyright (C) 2013 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 com.android.bitmap.drawable;
+
+import android.content.res.Resources;
+import android.graphics.Canvas;
+import android.graphics.ColorFilter;
+import android.graphics.Paint;
+import android.graphics.PixelFormat;
+import android.graphics.Rect;
+import android.graphics.drawable.Drawable;
+import android.util.DisplayMetrics;
+import android.util.Log;
+
+import com.android.bitmap.BitmapCache;
+import com.android.bitmap.DecodeTask;
+import com.android.bitmap.DecodeTask.Request;
+import com.android.bitmap.ReusableBitmap;
+import com.android.bitmap.util.BitmapUtils;
+import com.android.bitmap.util.RectUtils;
+import com.android.bitmap.util.Trace;
+
+import java.util.concurrent.Executor;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * This class encapsulates the basic functionality needed to display a single image bitmap,
+ * including request creation/cancelling, and data unbinding and re-binding.
+ * <p>
+ * The actual bitmap decode work is handled by {@link DecodeTask}.
+ */
+public class BasicBitmapDrawable extends Drawable implements DecodeTask.DecodeCallback,
+        Drawable.Callback {
+
+    private BitmapRequestKey mCurrKey;
+    private ReusableBitmap mBitmap;
+    private final BitmapCache mCache;
+    private DecodeTask mTask;
+    private int mDecodeWidth;
+    private int mDecodeHeight;
+
+    // based on framework CL:I015d77
+    private static final int CPU_COUNT = Runtime.getRuntime().availableProcessors();
+    private static final int CORE_POOL_SIZE = CPU_COUNT + 1;
+    private static final int MAXIMUM_POOL_SIZE = CPU_COUNT * 2 + 1;
+    private static final Executor SMALL_POOL_EXECUTOR = new ThreadPoolExecutor(
+            CORE_POOL_SIZE, MAXIMUM_POOL_SIZE, 1, TimeUnit.SECONDS,
+            new LinkedBlockingQueue<Runnable>(128));
+
+    private static final Executor EXECUTOR = SMALL_POOL_EXECUTOR;
+
+    private static final boolean LIMIT_BITMAP_DENSITY = true;
+
+    private static final int MAX_BITMAP_DENSITY = DisplayMetrics.DENSITY_HIGH;
+
+    private final float mDensity;
+    private final Paint mPaint = new Paint();
+    private final Rect mSrcRect = new Rect();
+
+    private static final String TAG = BasicBitmapDrawable.class.getSimpleName();
+    private static final boolean DEBUG = false;
+
+    public BasicBitmapDrawable(final Resources res, final BitmapCache cache) {
+        mDensity = res.getDisplayMetrics().density;
+        mCache = cache;
+        mPaint.setFilterBitmap(true);
+    }
+
+    public DecodeTask.Request getKey() {
+        return mCurrKey;
+    }
+
+    /**
+     * Set the dimensions to decode into.
+     */
+    public void setDecodeDimensions(int w, int h) {
+        mDecodeWidth = w;
+        mDecodeHeight = h;
+        decode();
+    }
+
+    public void unbind() {
+        setImage(null);
+    }
+
+    public void bind(BitmapRequestKey key) {
+        setImage(key);
+    }
+
+    private void setImage(final BitmapRequestKey key) {
+        if (mCurrKey != null && mCurrKey.equals(key)) {
+            return;
+        }
+
+        Trace.beginSection("set image");
+        Trace.beginSection("release reference");
+        if (mBitmap != null) {
+            mBitmap.releaseReference();
+            mBitmap = null;
+        }
+        Trace.endSection();
+        mCurrKey = key;
+
+        if (mTask != null) {
+            mTask.cancel();
+            mTask = null;
+        }
+
+        if (key == null) {
+            invalidateSelf();
+            Trace.endSection();
+            return;
+        }
+
+        // find cached entry here and skip decode if found.
+        final ReusableBitmap cached = mCache.get(key, true /* incrementRefCount */);
+        if (cached != null) {
+            setBitmap(cached);
+            if (DEBUG) {
+                Log.d(TAG, String.format("CACHE HIT key=%s", mCurrKey));
+            }
+        } else {
+            decode();
+            if (DEBUG) {
+                Log.d(TAG, String.format(
+                        "CACHE MISS key=%s\ncache=%s", mCurrKey, mCache.toDebugString()));
+            }
+        }
+        Trace.endSection();
+    }
+
+    @Override
+    public void draw(final Canvas canvas) {
+        final Rect bounds = getBounds();
+        if (bounds.isEmpty()) {
+            return;
+        }
+
+        if (mBitmap != null && mBitmap.bmp != null) {
+            BitmapUtils.calculateCroppedSrcRect(
+                    mBitmap.getLogicalWidth(), mBitmap.getLogicalHeight(),
+                    bounds.width(), bounds.height(),
+                    bounds.height(), Integer.MAX_VALUE,
+                    0.5f, false /* absoluteFraction */,
+                    1, mSrcRect);
+
+            final int orientation = mBitmap.getOrientation();
+            // calculateCroppedSrcRect() gave us the source rectangle "as if" the orientation has
+            // been corrected. We need to decode the uncorrected source rectangle. Calculate true
+            // coordinates.
+            RectUtils.rotateRectForOrientation(orientation,
+                    new Rect(0, 0, mBitmap.getLogicalWidth(), mBitmap.getLogicalHeight()),
+                    mSrcRect);
+
+            // We may need to rotate the canvas, so we also have to rotate the bounds.
+            final Rect rotatedBounds = new Rect(bounds);
+            RectUtils.rotateRect(orientation, bounds.centerX(), bounds.centerY(), rotatedBounds);
+
+            // Rotate the canvas.
+            canvas.save();
+            canvas.rotate(orientation, bounds.centerX(), bounds.centerY());
+            canvas.drawBitmap(mBitmap.bmp, mSrcRect, rotatedBounds, mPaint);
+            canvas.restore();
+        }
+    }
+
+    @Override
+    public void setAlpha(int alpha) {
+        final int old = mPaint.getAlpha();
+        mPaint.setAlpha(alpha);
+        if (alpha != old) {
+            invalidateSelf();
+        }
+    }
+
+    @Override
+    public void setColorFilter(ColorFilter cf) {
+        mPaint.setColorFilter(cf);
+        invalidateSelf();
+    }
+
+    @Override
+    public int getOpacity() {
+        return (mBitmap != null && (mBitmap.bmp.hasAlpha() || mPaint.getAlpha() < 255)) ?
+                PixelFormat.TRANSLUCENT : PixelFormat.OPAQUE;
+    }
+
+    @Override
+    public void onDecodeBegin(final Request key) { }
+
+    @Override
+    public void onDecodeComplete(final Request key, final ReusableBitmap result) {
+        if (key.equals(mCurrKey)) {
+            setBitmap(result);
+        } else {
+            // if the requests don't match (i.e. this request is stale), decrement the
+            // ref count to allow the bitmap to be pooled
+            if (result != null) {
+                result.releaseReference();
+            }
+        }
+    }
+
+    @Override
+    public void onDecodeCancel(final Request key) { }
+
+    private void setBitmap(ReusableBitmap bmp) {
+        if (mBitmap != null && mBitmap != bmp) {
+            mBitmap.releaseReference();
+        }
+        mBitmap = bmp;
+        invalidateSelf();
+    }
+
+    private void decode() {
+        final int bufferW;
+        final int bufferH;
+
+        if (mCurrKey == null) {
+            return;
+        }
+
+        Trace.beginSection("decode");
+        if (LIMIT_BITMAP_DENSITY) {
+            final float scale =
+                    Math.min(1f, (float) MAX_BITMAP_DENSITY / DisplayMetrics.DENSITY_DEFAULT
+                            / mDensity);
+            bufferW = (int) (mDecodeWidth * scale);
+            bufferH = (int) (mDecodeHeight * scale);
+        } else {
+            bufferW = mDecodeWidth;
+            bufferH = mDecodeHeight;
+        }
+
+        if (bufferW == 0 || bufferH == 0) {
+            Trace.endSection();
+            return;
+        }
+        if (mTask != null) {
+            mTask.cancel();
+        }
+        mTask = new DecodeTask(mCurrKey, bufferW, bufferH, this, mCache);
+        mTask.executeOnExecutor(EXECUTOR);
+        Trace.endSection();
+    }
+
+    @Override
+    public void invalidateDrawable(Drawable who) {
+        invalidateSelf();
+    }
+
+    @Override
+    public void scheduleDrawable(Drawable who, Runnable what, long when) {
+        scheduleSelf(what, when);
+    }
+
+    @Override
+    public void unscheduleDrawable(Drawable who, Runnable what) {
+        unscheduleSelf(what);
+    }
+}