Fix javadoc warnings in cronet's UploadDataProviders.java

components/cronet/android/api/src/org/chromium/net/UploadDataProviders.java

 // Copyright 2016 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;
 
 import android.os.ParcelFileDescriptor;
 
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.nio.channels.FileChannel;
 
 /**
  * Provides implementations of {@link UploadDataProvider} for common use cases.
  */
 public final class UploadDataProviders {
     /**
      * Uploads an entire file.
      *
      * @param file The file to upload
+     * @return A new UploadDataProvider for the given file
      */
     public static UploadDataProvider create(final File file) {
         return new FileUploadProvider(new FileChannelProvider() {
             @Override
             public FileChannel getChannel() throws IOException {
                 return new FileInputStream(file).getChannel();
             }
         });
     }
 
     /**
      * Uploads an entire file, closing the descriptor when it is no longer needed.
      *
      * @param fd The file descriptor to upload
      * @throws IllegalArgumentException if {@code fd} is not a file.
+     * @return A new UploadDataProvider for the given file descriptor
      */
     public static UploadDataProvider create(final ParcelFileDescriptor fd) {
         return new FileUploadProvider(new FileChannelProvider() {
             @Override
             public FileChannel getChannel() throws IOException {
                 if (fd.getStatSize() != -1) {
                     return new ParcelFileDescriptor.AutoCloseInputStream(fd).getChannel();
                 } else {
                     fd.close();
                     throw new IllegalArgumentException("Not a file: " + fd);
                 }
             }
         });
     }
 
     /**
      * Uploads a ByteBuffer, from the current {@code buffer.position()} to {@code buffer.limit()}
+     * @param buffer The data to upload
+     * @return A new UploadDataProvider for the given buffer
      */
     public static UploadDataProvider create(ByteBuffer buffer) {
         return new ByteBufferUploadProvider(buffer.slice());
     }
 
-    /** Uploads {@code length} bytes from {@code data}, starting from {@code offset} */
+    /**
+     * Uploads {@code length} bytes from {@code data}, starting from {@code offset}
+     * @param data Array containing data to upload
+     * @param offset Offset within data to start with
+     * @param length Number of bytes to upload
+     * @return A new UploadDataProvider for the given data
+     */
     public static UploadDataProvider create(byte[] data, int offset, int length) {
         return new ByteBufferUploadProvider(ByteBuffer.wrap(data, offset, length));
     }
 
-    /** Uploads the contents of {@code data} */
+    /**
+     * Uploads the contents of {@code data}
+     * @param data Array containing data to upload
+     * @return A new UploadDataProvider for the given data
+     */
     public static UploadDataProvider create(byte[] data) {
         return create(data, 0, data.length);
     }
 
     private interface FileChannelProvider { FileChannel getChannel() throws IOException; }
 
     private static final class FileUploadProvider extends UploadDataProvider {
         private volatile FileChannel mChannel;
         private final FileChannelProvider mProvider;
         /** Guards initalization of {@code mChannel} */
@@ skipping 87 matching lines @@
         @Override
         public void rewind(UploadDataSink uploadDataSink) {
             mUploadBuffer.position(0);
             uploadDataSink.onRewindSucceeded();
         }
     }
 
     // Prevent instantiation
     private UploadDataProviders() {}
 }