[Cronet] Initial implementation of HttpURLConnection

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

+// Copyright 2014 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 java.io.InputStream;
+import java.nio.ByteBuffer;
+
+/**
+ * Wrapper class to construct an InputSteam based on a ByteBuffer.
+ */
+class ByteBufferInputStream extends InputStream {
+
+    private final ByteBuffer mBuf;
+
+    public ByteBufferInputStream(ByteBuffer buf) {
+        // Makes a read-only copy of the buffer passed in.
+        mBuf = buf.asReadOnlyBuffer();
+    }
+
+    @Override
+    public int read() {
+        if (!mBuf.hasRemaining()) {
+            return -1;
+        }
+        return mBuf.get() & 0xFF;
+    }
+
+    @Override
+    public int read(byte[] bytes, int off, int len) {
+        if (!mBuf.hasRemaining()) {
+            return -1;
+        }
+
+        len = Math.min(len, mBuf.remaining());
+        mBuf.get(bytes, off, len);
+        return len;
+    }
+}