[Cronet] Implement getOutputStream in CronetHttpURLConnection

components/cronet/android/java/src/org/chromium/net/urlconnection/CronetBufferedOutputStream.java

Index: components/cronet/android/java/src/org/chromium/net/urlconnection/CronetBufferedOutputStream.java
diff --git a/components/cronet/android/java/src/org/chromium/net/urlconnection/CronetBufferedOutputStream.java b/components/cronet/android/java/src/org/chromium/net/urlconnection/CronetBufferedOutputStream.java
new file mode 100644
index 0000000000000000000000000000000000000000..9eb03bcf82c386f4b2e26e3129d8ada5a28f1ee3
--- /dev/null
+++ b/components/cronet/android/java/src/org/chromium/net/urlconnection/CronetBufferedOutputStream.java
@@ -0,0 +1,105 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.net.urlconnection;
+
+import org.chromium.net.UploadDataProvider;
+import org.chromium.net.UploadDataSink;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.nio.ByteBuffer;
+
+/**
+ * An implementation of {@link java.io.OutputStream} that buffers entire request
+ * body in memory. This is used when neither
+ * {@link CronetHttpURLConnection#setFixedLengthStreamingMode}
+ * or {@link CronetHttpURLConnection#setChunkedStreamingMode} is set.
+ */
+final class CronetBufferedOutputStream extends OutputStream
+        implements UploadDataProvider {
+    private final int mInitialContentLength;
+    private final CronetHttpURLConnection mConnection;
+    // Internal buffer that is used to buffer the request body.
+    private final ByteArrayOutputStream mBuffer;
+    // Number of bytes consumed by the native UploadDataStream.
+    private int mBytesConsumed;
+
+    /**
+     * Packaged protected constructor.

[mef, 2015/03/10 16:48:22]

nit: Package protected constructor.

[xunjieli, 2015/03/12 21:55:09]

Done.

+     * @param connection The CronetHttpURLConnection object.
+     * @param contentLength The content length of the request body. If content
+     *            length cannot be determined in advance, use -1.
+     */
+    CronetBufferedOutputStream(final CronetHttpURLConnection connection,
+            final long contentLength) {
+        if (connection == null) {
+            throw new NullPointerException();
+        }
+
+        if (contentLength > Integer.MAX_VALUE) {

[mef, 2015/03/10 16:48:22]

what if it is negative, but not -1?

[xunjieli, 2015/03/12 21:55:09]

Done. Right, we should handle that case. To make argument checking clearer, I
have separate the constructor into two. One is for when content length is known,
the other is when content length is unknown.

+            throw new IllegalStateException("Use setFixedLengthStreamingMode()"
+                + " or setChunkedStreamingMode() for requests larger than 2GB.");
+        }
+        mConnection = connection;
+        mInitialContentLength = (int) contentLength;
+        if (mInitialContentLength == -1) {
+            // Bufferring without knowing content-length.
+            mBuffer = new ByteArrayOutputStream();
+        } else {
+            mBuffer = new ByteArrayOutputStream(mInitialContentLength);
+        }
+        mBytesConsumed = 0;
+    }
+
+    @Override
+    public void write(int oneByte) throws IOException {
+        mBuffer.write((byte) oneByte);
+        if (mBuffer.size() == mInitialContentLength) {

[mef, 2015/03/10 16:48:22]

what happens if app will write more than expected?

[xunjieli, 2015/03/12 21:55:09]

Done. Good catch, it should fail with a java.net.ProtocolException. I have added
a test to verify against the default behavior.

+            // Entire post data has been received. Now start the request.
+            mConnection.connect();
+        }
+    }
+
+    @Override
+    public void write(byte[] buffer, int offset, int count) throws IOException {
+        mBuffer.write(buffer, offset, count);
+        if (mInitialContentLength != -1 && mBuffer.size() > mInitialContentLength) {
+            throw new IllegalStateException("Writing out of bound.");
+        }
+        if (mBuffer.size() == mInitialContentLength) {

[mef, 2015/03/10 16:48:22]

When does it connect() if mInitialContentLength == -1?

[xunjieli, 2015/03/12 21:55:09]

The embedder calls connect() or any function that implicitly calls connect()
(e.g/ getHttpStatusCode, getInputStream)

+            // Entire post data has been received. Now start the request.
+            mConnection.connect();
+        }
+    }
+
+    @Override

[mef, 2015/03/10 16:48:22]

nit: Add comment that these methods are implementation of UploadDataProvider.

[xunjieli, 2015/03/12 21:55:09]

Done.

+    public long getLength() {
+        // This method is supposed to be called just before starting the request.
+        // If content length is not initially passed in, the number of bytes
+        // written will be used as the content length.
+        if (mInitialContentLength < 0) {
+            return mBuffer.size();
+        }
+        return mInitialContentLength;
+    }
+
+    @Override
+    public void read(UploadDataSink uploadDataSink, ByteBuffer byteBuffer) {
+        int toConsume = Math.min(byteBuffer.remaining(),
+                mBuffer.size() - mBytesConsumed);
+        if (toConsume > 0) {
+            byteBuffer.put(mBuffer.toByteArray(), mBytesConsumed, toConsume);
+        }
+        mBytesConsumed += toConsume;
+        uploadDataSink.onReadSucceeded(false);
+    }
+
+    @Override
+    public void rewind(UploadDataSink uploadDataSink) {
+        mBytesConsumed = 0;
+        uploadDataSink.onRewindSucceeded();
+    }
+}