Import of Volley from GitHub to AOSP.

  - c9b2623cb524d2ec29a5a7f012528115f45b24cd Tolerate null header maps in HttpHeaderParser. (#334) by Jeff Davidson <jpd@google.com>
  - 455a16125ae9d01176d68a2ea7d4747130e55801 Allow creation of custom input/output streams in HurlStac... by Nicolas <ndagnas@live.fr>
  - addc11dbd37bd3a5d8136557076af0e8d0a995a4 Annotate more nullable methods and fields (#333) by Julien Biral <jbir789@users.noreply.github.com>
  - d41f34a43520cd1d30fe71ada3271161adb0e9c0 Add @Nullable annotations to Response (#325) by justin-morey <justin.morey@gmail.com>
  - 8a3a7baa07dda3fb4c5d561664470311c13d215b Send request to network when cache entry parsing fails (#... by Ulrike Hager <uhager42@gmail.com>
  - 514eac8c33492f69f62799dcd3669c877474626c Re-initialize the cache if the directory was deleted. (#2... by Ulrike Hager <uhager42@gmail.com>
  - b95b0159a14f053590cb18fd1cf3a1b159e478a1 Fix timezone formatting for RFC1123 on some Android devic... by Jeff Davidson <jpd@google.com>
  - 96c88101bcb6139fc9dd2ded4ef7c0008085d4b1 httpheaderparser: log invalid date headers only verbosely... by Florens <Floens@gmail.com>
  - 8e7a6dbf4dfbea56da48814ecf6e7270dcec9b0f Allow Volley.newRequestQueue() to be called on main threa... by Yuhan Zhao <poligun@gmail.com>

GitOrigin-RevId: c9b2623cb524d2ec29a5a7f012528115f45b24cd
Change-Id: I8e677f68212e6ba0812f398744895a1a12b6ed70

5 files changed, 143 insertions, 30 deletions

diff --git a/src/main/java/com/android/volley/toolbox/DiskBasedCache.java b/src/main/java/com/android/volley/toolbox/DiskBasedCache.java
index a6a0c83..d4310e0 100644
--- a/src/main/java/com/android/volley/toolbox/DiskBasedCache.java
+++ b/src/main/java/com/android/volley/toolbox/DiskBasedCache.java
@@ -55,8 +55,8 @@ public class DiskBasedCache implements Cache {
     /** Total amount of space currently used by the cache in bytes. */
     private long mTotalSize = 0;
 
-    /** The root directory to use for the cache. */
-    private final File mRootDirectory;
+    /** The supplier for the root directory to use for the cache. */
+    private final FileSupplier mRootDirectorySupplier;
 
     /** The maximum size of the cache in bytes. */
     private final int mMaxCacheSizeInBytes;
@@ -78,8 +78,27 @@ public class DiskBasedCache implements Cache {
      *     briefly exceed this size on disk when writing a new entry that pushes it over the limit
      *     until the ensuing pruning completes.
      */
-    public DiskBasedCache(File rootDirectory, int maxCacheSizeInBytes) {
-        mRootDirectory = rootDirectory;
+    public DiskBasedCache(final File rootDirectory, int maxCacheSizeInBytes) {
+        mRootDirectorySupplier =
+                new FileSupplier() {
+                    @Override
+                    public File get() {
+                        return rootDirectory;
+                    }
+                };
+        mMaxCacheSizeInBytes = maxCacheSizeInBytes;
+    }
+
+    /**
+     * Constructs an instance of the DiskBasedCache at the specified directory.
+     *
+     * @param rootDirectorySupplier The supplier for the root directory of the cache.
+     * @param maxCacheSizeInBytes The maximum size of the cache in bytes. Note that the cache may
+     *     briefly exceed this size on disk when writing a new entry that pushes it over the limit
+     *     until the ensuing pruning completes.
+     */
+    public DiskBasedCache(FileSupplier rootDirectorySupplier, int maxCacheSizeInBytes) {
+        mRootDirectorySupplier = rootDirectorySupplier;
         mMaxCacheSizeInBytes = maxCacheSizeInBytes;
     }
 
@@ -93,10 +112,20 @@ public class DiskBasedCache implements Cache {
         this(rootDirectory, DEFAULT_DISK_USAGE_BYTES);
     }
 
+    /**
+     * Constructs an instance of the DiskBasedCache at the specified directory using the default
+     * maximum cache size of 5MB.
+     *
+     * @param rootDirectorySupplier The supplier for the root directory of the cache.
+     */
+    public DiskBasedCache(FileSupplier rootDirectorySupplier) {
+        this(rootDirectorySupplier, DEFAULT_DISK_USAGE_BYTES);
+    }
+
     /** Clears the cache. Deletes all cached files from disk. */
     @Override
     public synchronized void clear() {
-        File[] files = mRootDirectory.listFiles();
+        File[] files = mRootDirectorySupplier.get().listFiles();
         if (files != null) {
             for (File file : files) {
                 file.delete();
@@ -150,13 +179,14 @@ public class DiskBasedCache implements Cache {
      */
     @Override
     public synchronized void initialize() {
-        if (!mRootDirectory.exists()) {
-            if (!mRootDirectory.mkdirs()) {
-                VolleyLog.e("Unable to create cache dir %s", mRootDirectory.getAbsolutePath());
+        File rootDirectory = mRootDirectorySupplier.get();
+        if (!rootDirectory.exists()) {
+            if (!rootDirectory.mkdirs()) {
+                VolleyLog.e("Unable to create cache dir %s", rootDirectory.getAbsolutePath());
             }
             return;
         }
-        File[] files = mRootDirectory.listFiles();
+        File[] files = rootDirectory.listFiles();
         if (files == null) {
             return;
         }
@@ -226,12 +256,12 @@ public class DiskBasedCache implements Cache {
             e.size = file.length();
             putEntry(key, e);
             pruneIfNeeded();
-            return;
         } catch (IOException e) {
-        }
-        boolean deleted = file.delete();
-        if (!deleted) {
-            VolleyLog.d("Could not clean up file %s", file.getAbsolutePath());
+            boolean deleted = file.delete();
+            if (!deleted) {
+                VolleyLog.d("Could not clean up file %s", file.getAbsolutePath());
+            }
+            initializeIfRootDirectoryDeleted();
         }
     }
 
@@ -262,7 +292,22 @@ public class DiskBasedCache implements Cache {
 
     /** Returns a file object for the given cache key. */
     public File getFileForKey(String key) {
-        return new File(mRootDirectory, getFilenameForKey(key));
+        return new File(mRootDirectorySupplier.get(), getFilenameForKey(key));
+    }
+
+    /** Re-initialize the cache if the directory was deleted. */
+    private void initializeIfRootDirectoryDeleted() {
+        if (!mRootDirectorySupplier.get().exists()) {
+            VolleyLog.d("Re-initializing cache after external clearing.");
+            mEntries.clear();
+            mTotalSize = 0;
+            initialize();
+        }
+    }
+
+    /** Represents a supplier for {@link File}s. */
+    public interface FileSupplier {
+        File get();
     }
 
     /** Prunes the cache to fit the maximum size. */
diff --git a/src/main/java/com/android/volley/toolbox/HttpHeaderParser.java b/src/main/java/com/android/volley/toolbox/HttpHeaderParser.java
index 27d1268..1b410af 100644
--- a/src/main/java/com/android/volley/toolbox/HttpHeaderParser.java
+++ b/src/main/java/com/android/volley/toolbox/HttpHeaderParser.java
@@ -16,6 +16,7 @@
 
 package com.android.volley.toolbox;
 
+import androidx.annotation.Nullable;
 import com.android.volley.Cache;
 import com.android.volley.Header;
 import com.android.volley.NetworkResponse;
@@ -37,7 +38,11 @@ public class HttpHeaderParser {
 
     private static final String DEFAULT_CONTENT_CHARSET = "ISO-8859-1";
 
-    private static final String RFC1123_FORMAT = "EEE, dd MMM yyyy HH:mm:ss zzz";
+    private static final String RFC1123_PARSE_FORMAT = "EEE, dd MMM yyyy HH:mm:ss zzz";
+
+    // Hardcode 'GMT' rather than using 'zzz' since some platforms append an extraneous +00:00.
+    // See #287.
+    private static final String RFC1123_OUTPUT_FORMAT = "EEE, dd MMM yyyy HH:mm:ss 'GMT'";
 
     /**
      * Extracts a {@link com.android.volley.Cache.Entry} from a {@link NetworkResponse}.
@@ -45,10 +50,14 @@ public class HttpHeaderParser {
      * @param response The network response to parse headers from
      * @return a cache entry for the given response, or null if the response is not cacheable.
      */
+    @Nullable
     public static Cache.Entry parseCacheHeaders(NetworkResponse response) {
         long now = System.currentTimeMillis();
 
         Map<String, String> headers = response.headers;
+        if (headers == null) {
+            return null;
+        }
 
         long serverDate = 0;
         long lastModified = 0;
@@ -132,21 +141,29 @@ public class HttpHeaderParser {
     public static long parseDateAsEpoch(String dateStr) {
         try {
             // Parse date in RFC1123 format if this header contains one
-            return newRfc1123Formatter().parse(dateStr).getTime();
+            return newUsGmtFormatter(RFC1123_PARSE_FORMAT).parse(dateStr).getTime();
         } catch (ParseException e) {
             // Date in invalid format, fallback to 0
-            VolleyLog.e(e, "Unable to parse dateStr: %s, falling back to 0", dateStr);
+            // If the value is either "0" or "-1" we only log to verbose,
+            // these values are pretty common and cause log spam.
+            String message = "Unable to parse dateStr: %s, falling back to 0";
+            if ("0".equals(dateStr) || "-1".equals(dateStr)) {
+                VolleyLog.v(message, dateStr);
+            } else {
+                VolleyLog.e(e, message, dateStr);
+            }
+
             return 0;
         }
     }
 
     /** Format an epoch date in RFC1123 format. */
     static String formatEpochAsRfc1123(long epoch) {
-        return newRfc1123Formatter().format(new Date(epoch));
+        return newUsGmtFormatter(RFC1123_OUTPUT_FORMAT).format(new Date(epoch));
     }
 
-    private static SimpleDateFormat newRfc1123Formatter() {
-        SimpleDateFormat formatter = new SimpleDateFormat(RFC1123_FORMAT, Locale.US);
+    private static SimpleDateFormat newUsGmtFormatter(String format) {
+        SimpleDateFormat formatter = new SimpleDateFormat(format, Locale.US);
         formatter.setTimeZone(TimeZone.getTimeZone("GMT"));
         return formatter;
     }
@@ -159,7 +176,11 @@ public class HttpHeaderParser {
      * @return Returns the charset specified in the Content-Type of this header, or the
      *     defaultCharset if none can be found.
      */
-    public static String parseCharset(Map<String, String> headers, String defaultCharset) {
+    public static String parseCharset(
+            @Nullable Map<String, String> headers, String defaultCharset) {
+        if (headers == null) {
+            return defaultCharset;
+        }
         String contentType = headers.get(HEADER_CONTENT_TYPE);
         if (contentType != null) {
             String[] params = contentType.split(";", 0);
@@ -180,7 +201,7 @@ public class HttpHeaderParser {
      * Returns the charset specified in the Content-Type of this header, or the HTTP default
      * (ISO-8859-1) if none can be found.
      */
-    public static String parseCharset(Map<String, String> headers) {
+    public static String parseCharset(@Nullable Map<String, String> headers) {
         return parseCharset(headers, DEFAULT_CONTENT_CHARSET);
     }
 
diff --git a/src/main/java/com/android/volley/toolbox/HurlStack.java b/src/main/java/com/android/volley/toolbox/HurlStack.java
index f85d42c..9c38023 100644
--- a/src/main/java/com/android/volley/toolbox/HurlStack.java
+++ b/src/main/java/com/android/volley/toolbox/HurlStack.java
@@ -25,6 +25,7 @@ import java.io.DataOutputStream;
 import java.io.FilterInputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.io.OutputStream;
 import java.net.HttpURLConnection;
 import java.net.URL;
 import java.util.ArrayList;
@@ -111,7 +112,7 @@ public class HurlStack extends BaseHttpStack {
                     responseCode,
                     convertHeaders(connection.getHeaderFields()),
                     connection.getContentLength(),
-                    new UrlConnectionInputStream(connection));
+                    createInputStream(request, connection));
         } finally {
             if (!keepConnectionOpen) {
                 connection.disconnect();
@@ -169,6 +170,19 @@ public class HurlStack extends BaseHttpStack {
     }
 
     /**
+     * Create and return an InputStream from which the response will be read.
+     *
+     * <p>May be overridden by subclasses to manipulate or monitor this input stream.
+     *
+     * @param request current request.
+     * @param connection current connection of request.
+     * @return an InputStream from which the response will be read.
+     */
+    protected InputStream createInputStream(Request<?> request, HttpURLConnection connection) {
+        return new UrlConnectionInputStream(connection);
+    }
+
+    /**
      * Initializes an {@link InputStream} from the given {@link HttpURLConnection}.
      *
      * @param connection
@@ -223,7 +237,7 @@ public class HurlStack extends BaseHttpStack {
     // NOTE: Any request headers added here (via setRequestProperty or addRequestProperty) should be
     // checked against the existing properties in the connection and not overridden if already set.
     @SuppressWarnings("deprecation")
-    /* package */ static void setConnectionParametersForRequest(
+    /* package */ void setConnectionParametersForRequest(
             HttpURLConnection connection, Request<?> request) throws IOException, AuthFailureError {
         switch (request.getMethod()) {
             case Method.DEPRECATED_GET_OR_POST:
@@ -270,7 +284,7 @@ public class HurlStack extends BaseHttpStack {
         }
     }
 
-    private static void addBodyIfExists(HttpURLConnection connection, Request<?> request)
+    private void addBodyIfExists(HttpURLConnection connection, Request<?> request)
             throws IOException, AuthFailureError {
         byte[] body = request.getBody();
         if (body != null) {
@@ -278,7 +292,7 @@ public class HurlStack extends BaseHttpStack {
         }
     }
 
-    private static void addBody(HttpURLConnection connection, Request<?> request, byte[] body)
+    private void addBody(HttpURLConnection connection, Request<?> request, byte[] body)
             throws IOException {
         // Prepare output. There is no need to set Content-Length explicitly,
         // since this is handled by HttpURLConnection using the size of the prepared
@@ -289,8 +303,25 @@ public class HurlStack extends BaseHttpStack {
             connection.setRequestProperty(
                     HttpHeaderParser.HEADER_CONTENT_TYPE, request.getBodyContentType());
         }
-        DataOutputStream out = new DataOutputStream(connection.getOutputStream());
+        DataOutputStream out =
+                new DataOutputStream(createOutputStream(request, connection, body.length));
         out.write(body);
         out.close();
     }
+
+    /**
+     * Create and return an OutputStream to which the request body will be written.
+     *
+     * <p>May be overridden by subclasses to manipulate or monitor this output stream.
+     *
+     * @param request current request.
+     * @param connection current connection of request.
+     * @param length size of stream to write.
+     * @return an OutputStream to which the request body will be written.
+     * @throws IOException if an I/O error occurs while creating the stream.
+     */
+    protected OutputStream createOutputStream(
+            Request<?> request, HttpURLConnection connection, int length) throws IOException {
+        return connection.getOutputStream();
+    }
 }
diff --git a/src/main/java/com/android/volley/toolbox/ImageLoader.java b/src/main/java/com/android/volley/toolbox/ImageLoader.java
index b80072b..eece2cf 100644
--- a/src/main/java/com/android/volley/toolbox/ImageLoader.java
+++ b/src/main/java/com/android/volley/toolbox/ImageLoader.java
@@ -20,6 +20,7 @@ import android.os.Looper;
 import android.widget.ImageView;
 import android.widget.ImageView.ScaleType;
 import androidx.annotation.MainThread;
+import androidx.annotation.Nullable;
 import com.android.volley.Request;
 import com.android.volley.RequestQueue;
 import com.android.volley.Response.ErrorListener;
@@ -70,6 +71,7 @@ public class ImageLoader {
      * LruCache is recommended.
      */
     public interface ImageCache {
+        @Nullable
         Bitmap getBitmap(String url);
 
         void putBitmap(String url, Bitmap bitmap);
diff --git a/src/main/java/com/android/volley/toolbox/Volley.java b/src/main/java/com/android/volley/toolbox/Volley.java
index 1982802..bc65c9c 100644
--- a/src/main/java/com/android/volley/toolbox/Volley.java
+++ b/src/main/java/com/android/volley/toolbox/Volley.java
@@ -86,8 +86,22 @@ public class Volley {
     }
 
     private static RequestQueue newRequestQueue(Context context, Network network) {
-        File cacheDir = new File(context.getCacheDir(), DEFAULT_CACHE_DIR);
-        RequestQueue queue = new RequestQueue(new DiskBasedCache(cacheDir), network);
+        final Context appContext = context.getApplicationContext();
+        // Use a lazy supplier for the cache directory so that newRequestQueue() can be called on
+        // main thread without causing strict mode violation.
+        DiskBasedCache.FileSupplier cacheSupplier =
+                new DiskBasedCache.FileSupplier() {
+                    private File cacheDir = null;
+
+                    @Override
+                    public File get() {
+                        if (cacheDir == null) {
+                            cacheDir = new File(appContext.getCacheDir(), DEFAULT_CACHE_DIR);
+                        }
+                        return cacheDir;
+                    }
+                };
+        RequestQueue queue = new RequestQueue(new DiskBasedCache(cacheSupplier), network);
         queue.start();
         return queue;
     }