1 files changed, 47 insertions, 0 deletions
diff --git a/library/src/main/java/com/davemorrissey/labs/subscaleview/decoder/CompatDecoderFactory.java b/library/src/main/java/com/davemorrissey/labs/subscaleview/decoder/CompatDecoderFactory.java
new file mode 100644
index 0000000..870489f
--- /dev/null
+++ b/library/src/main/java/com/davemorrissey/labs/subscaleview/decoder/CompatDecoderFactory.java
@@ -0,0 +1,47 @@
+package com.davemorrissey.labs.subscaleview.decoder;
+
+import android.graphics.Bitmap;
+import android.support.annotation.NonNull;
+
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+
+/**
+ * Compatibility factory to instantiate decoders with empty public constructors.
+ * @param <T> The base type of the decoder this factory will produce.
+ */
+@SuppressWarnings("WeakerAccess")
+public class CompatDecoderFactory<T> implements DecoderFactory<T> {
+
+    private final Class<? extends T> clazz;
+    private final Bitmap.Config bitmapConfig;
+
+    /**
+     * Construct a factory for the given class. This must have a default constructor.
+     * @param clazz a class that implements {@link ImageDecoder} or {@link ImageRegionDecoder}.
+     */
+    public CompatDecoderFactory(@NonNull Class<? extends T> clazz) {
+    this(clazz, null);
+    }
+
+    /**
+     * Construct a factory for the given class. This must have a constructor that accepts a {@link Bitmap.Config} instance.
+     * @param clazz a class that implements {@link ImageDecoder} or {@link ImageRegionDecoder}.
+     * @param bitmapConfig bitmap configuration to be used when loading images.
+     */
+    public CompatDecoderFactory(@NonNull Class<? extends T> clazz, Bitmap.Config bitmapConfig) {
+        this.clazz = clazz;
+        this.bitmapConfig = bitmapConfig;
+    }
+
+    @Override
+    public T make() throws IllegalAccessException, InstantiationException, NoSuchMethodException, InvocationTargetException {
+        if (bitmapConfig == null) {
+            return clazz.newInstance();
+        } else {
+            Constructor<? extends T> ctor = clazz.getConstructor(Bitmap.Config.class);
+            return ctor.newInstance(bitmapConfig);
+        }
+    }
+
+}