Import of Volley from GitHub to AOSP. am: 82e4a43fe7 am: fa08a1a64c
am: 5d73fc5fbe
Change-Id: Ib499936e8d0357f3215286b9352e8a8d70be159a
diff --git a/src/main/java/com/android/volley/ExecutorDelivery.java b/src/main/java/com/android/volley/ExecutorDelivery.java
index 1babfcd..f36fb75 100644
--- a/src/main/java/com/android/volley/ExecutorDelivery.java
+++ b/src/main/java/com/android/volley/ExecutorDelivery.java
@@ -88,6 +88,13 @@
@SuppressWarnings("unchecked")
@Override
public void run() {
+ // NOTE: If cancel() is called off the thread that we're currently running in (by
+ // default, the main thread), we cannot guarantee that deliverResponse()/deliverError()
+ // won't be called, since it may be canceled after we check isCanceled() but before we
+ // deliver the response. Apps concerned about this guarantee must either call cancel()
+ // from the same thread or implement their own guarantee about not invoking their
+ // listener after cancel() has been called.
+
// If this request has canceled, finish it and don't deliver.
if (mRequest.isCanceled()) {
mRequest.finish("canceled-at-delivery");
diff --git a/src/main/java/com/android/volley/Request.java b/src/main/java/com/android/volley/Request.java
index a98277e..358a327 100644
--- a/src/main/java/com/android/volley/Request.java
+++ b/src/main/java/com/android/volley/Request.java
@@ -83,8 +83,12 @@
/** Default tag for {@link TrafficStats}. */
private final int mDefaultTrafficStatsTag;
+ /** Lock to guard state which can be mutated after a request is added to the queue. */
+ private final Object mLock = new Object();
+
/** Listener interface for errors. */
- private final Response.ErrorListener mErrorListener;
+ // @GuardedBy("mLock")
+ private Response.ErrorListener mErrorListener;
/** Sequence number of this request, used to enforce FIFO ordering. */
private Integer mSequence;
@@ -96,9 +100,11 @@
private boolean mShouldCache = true;
/** Whether or not this request has been canceled. */
+ // @GuardedBy("mLock")
private boolean mCanceled = false;
/** Whether or not a response has been delivered for this request yet. */
+ // @GuardedBy("mLock")
private boolean mResponseDelivered = false;
/** Whether the request should be retried in the event of an HTTP 5xx (server) error. */
@@ -118,11 +124,9 @@
private Object mTag;
/** Listener that will be notified when a response has been delivered. */
+ // @GuardedBy("mLock")
private NetworkRequestCompleteListener mRequestCompleteListener;
- /** Object to guard access to mRequestCompleteListener. */
- private final Object mLock = new Object();
-
/**
* Creates a new request with the given URL and error listener. Note that
* the normal response listener is not provided here as delivery of responses
@@ -320,17 +324,34 @@
}
/**
- * Mark this request as canceled. No callback will be delivered.
+ * Mark this request as canceled.
+ *
+ * <p>No callback will be delivered as long as either:
+ * <ul>
+ * <li>This method is called on the same thread as the {@link ResponseDelivery} is running
+ * on. By default, this is the main thread.
+ * <li>The request subclass being used overrides cancel() and ensures that it does not
+ * invoke the listener in {@link #deliverResponse} after cancel() has been called in a
+ * thread-safe manner.
+ * </ul>
+ *
+ * <p>There are no guarantees if both of these conditions aren't met.
*/
+ // @CallSuper
public void cancel() {
- mCanceled = true;
+ synchronized (mLock) {
+ mCanceled = true;
+ mErrorListener = null;
+ }
}
/**
* Returns true if this request has been canceled.
*/
public boolean isCanceled() {
- return mCanceled;
+ synchronized (mLock) {
+ return mCanceled;
+ }
}
/**
@@ -549,14 +570,18 @@
* later in the request's lifetime for suppressing identical responses.
*/
public void markDelivered() {
- mResponseDelivered = true;
+ synchronized (mLock) {
+ mResponseDelivered = true;
+ }
}
/**
* Returns true if this request has had a response delivered for it.
*/
public boolean hasHadResponseDelivered() {
- return mResponseDelivered;
+ synchronized (mLock) {
+ return mResponseDelivered;
+ }
}
/**
@@ -597,8 +622,12 @@
* @param error Error details
*/
public void deliverError(VolleyError error) {
- if (mErrorListener != null) {
- mErrorListener.onErrorResponse(error);
+ Response.ErrorListener listener;
+ synchronized (mLock) {
+ listener = mErrorListener;
+ }
+ if (listener != null) {
+ listener.onErrorResponse(error);
}
}
@@ -619,10 +648,12 @@
* @param response received from the network
*/
/* package */ void notifyListenerResponseReceived(Response<?> response) {
+ NetworkRequestCompleteListener listener;
synchronized (mLock) {
- if (mRequestCompleteListener != null) {
- mRequestCompleteListener.onResponseReceived(this, response);
- }
+ listener = mRequestCompleteListener;
+ }
+ if (listener != null) {
+ listener.onResponseReceived(this, response);
}
}
@@ -631,10 +662,12 @@
* a response which can be used for other, waiting requests.
*/
/* package */ void notifyListenerResponseNotUsable() {
+ NetworkRequestCompleteListener listener;
synchronized (mLock) {
- if (mRequestCompleteListener != null) {
- mRequestCompleteListener.onNoUsableResponseReceived(this);
- }
+ listener = mRequestCompleteListener;
+ }
+ if (listener != null) {
+ listener.onNoUsableResponseReceived(this);
}
}
diff --git a/src/main/java/com/android/volley/toolbox/ImageRequest.java b/src/main/java/com/android/volley/toolbox/ImageRequest.java
index 0f33cd8..1db7e35 100644
--- a/src/main/java/com/android/volley/toolbox/ImageRequest.java
+++ b/src/main/java/com/android/volley/toolbox/ImageRequest.java
@@ -42,7 +42,11 @@
/** Default backoff multiplier for image requests */
public static final float DEFAULT_IMAGE_BACKOFF_MULT = 2f;
- private final Response.Listener<Bitmap> mListener;
+ /** Lock to guard mListener as it is cleared on cancel() and read on delivery. */
+ private final Object mLock = new Object();
+
+ // @GuardedBy("mLock")
+ private Response.Listener<Bitmap> mListener;
private final Config mDecodeConfig;
private final int mMaxWidth;
private final int mMaxHeight;
@@ -215,9 +219,21 @@
}
@Override
+ public void cancel() {
+ super.cancel();
+ synchronized (mLock) {
+ mListener = null;
+ }
+ }
+
+ @Override
protected void deliverResponse(Bitmap response) {
- if (mListener != null) {
- mListener.onResponse(response);
+ Response.Listener<Bitmap> listener;
+ synchronized (mLock) {
+ listener = mListener;
+ }
+ if (listener != null) {
+ listener.onResponse(response);
}
}
diff --git a/src/main/java/com/android/volley/toolbox/JsonRequest.java b/src/main/java/com/android/volley/toolbox/JsonRequest.java
index 40877b1..f291076 100644
--- a/src/main/java/com/android/volley/toolbox/JsonRequest.java
+++ b/src/main/java/com/android/volley/toolbox/JsonRequest.java
@@ -39,7 +39,11 @@
private static final String PROTOCOL_CONTENT_TYPE =
String.format("application/json; charset=%s", PROTOCOL_CHARSET);
- private final Listener<T> mListener;
+ /** Lock to guard mListener as it is cleared on cancel() and read on delivery. */
+ private final Object mLock = new Object();
+
+ // @GuardedBy("mLock")
+ private Listener<T> mListener;
private final String mRequestBody;
/**
@@ -62,9 +66,21 @@
}
@Override
+ public void cancel() {
+ super.cancel();
+ synchronized (mLock) {
+ mListener = null;
+ }
+ }
+
+ @Override
protected void deliverResponse(T response) {
- if (mListener != null) {
- mListener.onResponse(response);
+ Response.Listener<T> listener;
+ synchronized (mLock) {
+ listener = mListener;
+ }
+ if (listener != null) {
+ listener.onResponse(response);
}
}
diff --git a/src/main/java/com/android/volley/toolbox/StringRequest.java b/src/main/java/com/android/volley/toolbox/StringRequest.java
index 05a62f6..9deba1d 100644
--- a/src/main/java/com/android/volley/toolbox/StringRequest.java
+++ b/src/main/java/com/android/volley/toolbox/StringRequest.java
@@ -28,7 +28,12 @@
* A canned request for retrieving the response body at a given URL as a String.
*/
public class StringRequest extends Request<String> {
- private final Listener<String> mListener;
+
+ /** Lock to guard mListener as it is cleared on cancel() and read on delivery. */
+ private final Object mLock = new Object();
+
+ // @GuardedBy("mLock")
+ private Listener<String> mListener;
/**
* Creates a new request with the given method.
@@ -56,9 +61,21 @@
}
@Override
+ public void cancel() {
+ super.cancel();
+ synchronized (mLock) {
+ mListener = null;
+ }
+ }
+
+ @Override
protected void deliverResponse(String response) {
- if (mListener != null) {
- mListener.onResponse(response);
+ Response.Listener<String> listener;
+ synchronized (mLock) {
+ listener = mListener;
+ }
+ if (listener != null) {
+ listener.onResponse(response);
}
}
