Synchronous StreamOpener -> Async StreamLoader

An extensive but relatively minor change to the
internal interfaces to allow for asynchronous 
InputStream opening in the ImageManager. This
allows us to use async http libraries (like 
Volley) without forcing us to always start a 
download and then check the ImageManager cache
only after the download completes.

library/src/com/bumptech/glide/Glide.java

@@ -5,9 +5,9 @@
 import android.view.animation.AnimationUtils;
 import android.widget.ImageView;
 import com.bumptech.glide.loader.image.ImageLoader;
-import com.bumptech.glide.loader.model.FileStreamLoader;
-import com.bumptech.glide.loader.model.ModelStreamLoader;
-import com.bumptech.glide.loader.model.UrlStreamLoader;
+import com.bumptech.glide.loader.model.FileLoader;
+import com.bumptech.glide.loader.model.ModelLoader;
+import com.bumptech.glide.loader.model.UrlLoader;
 import com.bumptech.glide.presenter.ImagePresenter;
 import com.bumptech.glide.presenter.ImageSetCallback;
 import com.bumptech.glide.resize.ImageManager;
@@ -17,8 +17,6 @@
 
 import java.io.File;
 import java.net.URL;
-import java.util.HashMap;
-import java.util.Map;
 
 /**
  * Static helper methods/classes to present a simple unified interface for using glide. Allows 90%
@@ -28,17 +26,25 @@
  */
 public class Glide {
     private static final Glide GLIDE = new Glide();
-    private static final Map<Class, ModelStreamLoader> classToModelStream = new HashMap<Class, ModelStreamLoader>() {{
-        put(File.class, new FileStreamLoader());
-        put(URL.class, new UrlStreamLoader());
-    }};
 
     private ImageManager imageManager;
 
     public static Glide get() {
         return GLIDE;
     }
 
+    @SuppressWarnings("unchecked")
+    private static <T> ModelLoader<T> getModelFor(T model) {
+        if (model == URL.class) {
+            return (ModelLoader<T>) new UrlLoader();
+        } else if (model == File.class) {
+            return (ModelLoader<T>) new FileLoader();
+        } else {
+            throw new IllegalArgumentException("No default ModelLoader for class=" + model.getClass() +
+                    ", you need to provide one by calling with()");
+        }
+    }
+
     protected Glide() { }
 
     /**
@@ -127,8 +133,9 @@ public static class Request<T> {
 
         private ImagePresenter<T> presenter;
         private ImagePresenter.Builder<T> builder;
-        private ModelStreamLoader<T> modelStreamLoader = null;
+        private ModelLoader<T> modelLoader = null;
 
+        @SuppressWarnings("unchecked")
         public Request(T model, ImageView imageView) {
             this.model = model;
             this.imageView = imageView;
@@ -138,29 +145,24 @@ public Request(T model, ImageView imageView) {
             builder = new ImagePresenter.Builder<T>()
                     .setImageView(imageView)
                     .setImageLoader(new Approximate(getImageManager()));
-
-            ModelStreamLoader<T> loader = classToModelStream.get(model.getClass());
-            if (loader != null) {
-                builder.setModelStreamLoader(loader);
-            }
         }
 
         /**
-         * Set the {@link ModelStreamLoader} for the model. For URL models, defaults to {@link UrlStreamLoader},
-         * for File models, defaults to {@link FileStreamLoader}.
+         * Set the {@link ModelLoader} for the model. For URL models, defaults to {@link UrlLoader},
+         * for File models, defaults to {@link FileLoader}.
          *
-         * @param modelStreamLoader The {@link ModelStreamLoader} to use. Replaces any existing loader
+         * @param modelLoader The {@link ModelLoader} to use. Replaces any existing loader
          * @return This Request
          */
-        public Request<T> with(ModelStreamLoader<T> modelStreamLoader) {
-            this.modelStreamLoader = modelStreamLoader;
-            builder.setModelStreamLoader(modelStreamLoader);
+        public Request<T> with(ModelLoader<T> modelLoader) {
+            this.modelLoader = modelLoader;
+            builder.setModelLoader(modelLoader);
 
             return this;
         }
 
         /**
-         * Resizes models using {@link ImageManager#centerCrop(String, com.bumptech.glide.loader.opener.StreamOpener, int, int, com.bumptech.glide.resize.LoadedCallback)}
+         * Resizes models using {@link ImageManager#centerCrop(String, com.bumptech.glide.loader.stream.StreamLoader, int, int, com.bumptech.glide.resize.LoadedCallback)}
          * Replaces any existing resize style
          *
          * @return This Request
@@ -170,7 +172,7 @@ public Request<T> centerCrop() {
         }
 
         /**
-         * Resizes models using {@link ImageManager#fitCenter(String, com.bumptech.glide.loader.opener.StreamOpener, int, int, com.bumptech.glide.resize.LoadedCallback)}
+         * Resizes models using {@link ImageManager#fitCenter(String, com.bumptech.glide.loader.stream.StreamLoader, int, int, com.bumptech.glide.resize.LoadedCallback)}
          * Replaces any existing resize style
          *
          * @return This Request
@@ -180,7 +182,7 @@ public Request<T> fitCenter() {
         }
 
         /**
-         * Resizes models using {@link ImageManager#getImageApproximate(String, com.bumptech.glide.loader.opener.StreamOpener, int, int, com.bumptech.glide.resize.LoadedCallback)}
+         * Resizes models using {@link ImageManager#getImageApproximate(String, com.bumptech.glide.loader.stream.StreamLoader, int, int, com.bumptech.glide.resize.LoadedCallback)}
          * Replaces any existing resize style
          *
          * @return This Request
@@ -259,9 +261,8 @@ private ImageManager getImageManager() {
          */
         private void build() {
             if (presenter == null) {
-                if (modelStreamLoader == null) {
-                    throw new IllegalArgumentException("You must set a ModelStreamLoader for model class=" +
-                            model.getClass());
+                if (modelLoader == null) {
+                    modelLoader = getModelFor(model);
                 }
                 presenter = builder.build();
                 imageView.setTag(R.id.image_presenter_id, presenter);

library/src/com/bumptech/glide/loader/image/BaseImageLoader.java

@@ -1,7 +1,7 @@
 package com.bumptech.glide.loader.image;
 
 import android.graphics.Bitmap;
-import com.bumptech.glide.loader.opener.StreamOpener;
+import com.bumptech.glide.loader.stream.StreamLoader;
 
 import java.lang.ref.WeakReference;
 
@@ -12,8 +12,8 @@
  */
 public abstract class BaseImageLoader implements ImageLoader {
     @Override
-    public final Object fetchImage(String id, StreamOpener streamOpener, int width, int height, ImageReadyCallback cb) {
-        doFetchImage(id, streamOpener, width, height, new InternalImageReadyCallback(cb, id));
+    public final Object fetchImage(String id, StreamLoader streamLoader, int width, int height, ImageReadyCallback cb) {
+        doFetchImage(id, streamLoader, width, height, new InternalImageReadyCallback(cb, id));
         return cb;
     }
 
@@ -26,15 +26,16 @@ public void clear() { }
      * it. Once a load completes or fails the given callback should be called to signal to the calling object that the
      * image is ready.
      *
-     * @see ImageLoader#fetchImage(String, com.bumptech.glide.loader.opener.StreamOpener, int, int, com.bumptech.glide.loader.image.ImageLoader.ImageReadyCallback)
+     * @see ImageLoader#fetchImage(String, com.bumptech.glide.loader.stream.StreamLoader, int, int, com.bumptech.glide.loader.image.ImageLoader.ImageReadyCallback)
      *
-     * @param id A unique id identifying this particular image that will be combined with the provided size info to use as a cache key.
-     * @param streamOpener The {@link StreamOpener} that will be used to load the image if it is not cached
+     * @param id A string id that uniquely identifies the image to be loaded. It may include the width and height, but
+     *           is not required to do so
+     * @param streamLoader The {@link StreamLoader} that will be used to load the image if it is not cached
      * @param width The width of the view where the image will be displayed
      * @param height The height of the view where the image will be displayed
      * @param cb The callback to call when the bitmap is loaded into memory, or when a load fails
      */
-    protected abstract void doFetchImage(String id, StreamOpener streamOpener, int width, int height, ImageReadyCallback cb);
+    protected abstract void doFetchImage(String id, StreamLoader streamLoader, int width, int height, ImageReadyCallback cb);
 
     /**
      * A lifecycle method called after the requesting object is notified that this loader has loaded a bitmap. Should be

library/src/com/bumptech/glide/loader/image/ImageLoader.java

@@ -1,7 +1,7 @@
 package com.bumptech.glide.loader.image;
 
 import android.graphics.Bitmap;
-import com.bumptech.glide.loader.opener.StreamOpener;
+import com.bumptech.glide.loader.stream.StreamLoader;
 
 /**
  * An interface used by {@link com.bumptech.glide.presenter.ImagePresenter} to fetch a bitmap for a given id and
@@ -35,15 +35,16 @@ public interface ImageReadyCallback {
     /**
      * Load the image at the given path represented by the given model
      *
-     * @param id A unique id identifying this particular image that will be combined with the provided size info to use as a cache key.
-     * @param streamOpener The {@link StreamOpener} that will be used to load the image if it is not cached
+     * @param id A string id that uniquely identifies the image to be loaded. It may include the width and height, but
+     *           is not required to do so
+     * @param streamLoader The {@link StreamLoader} that will be used to load the image if it is not cached
      * @param width The width of the view where the image will be displayed
      * @param height The height of the view where the image will be displayed
      * @param cb The callback to call when the bitmap is loaded into memory, or when a load fails
      *
      * @return A reference to the fetch that must be retained by the calling object as long as the fetch is relevant
      */
-    public Object fetchImage(String id, StreamOpener streamOpener, int width, int height, ImageReadyCallback cb);
+    public Object fetchImage(String id, StreamLoader streamLoader, int width, int height, ImageReadyCallback cb);
 
     /**
      * Called when the current image load does not need to continue and any corresponding cleanup to save cpu

library/src/com/bumptech/glide/loader/model/FileLoader.java

@@ -0,0 +1,26 @@
+package com.bumptech.glide.loader.model;
+
+import com.bumptech.glide.loader.stream.FileStreamLoader;
+import com.bumptech.glide.loader.stream.StreamLoader;
+
+import java.io.File;
+
+/**
+ * A simple model loader for {@link File}
+ */
+public class FileLoader implements ModelLoader<File> {
+
+    @Override
+    public StreamLoader getStreamOpener(File model, int width, int height) {
+        return new FileStreamLoader(model);
+    }
+
+    @Override
+    public String getId(File model) {
+        //canonical is better, but also slower
+        return model.getAbsolutePath();
+    }
+
+    @Override
+    public void clear() { }
+}