content: /*
   * Copyright (C) 2016 The Android Open Source Project
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package com.android.apksig.util;
  
  import com.android.apksig.internal.util.ByteArrayDataSink;
  import com.android.apksig.internal.util.MessageDigestSink;
  import com.android.apksig.internal.util.OutputStreamDataSink;
  import com.android.apksig.internal.util.RandomAccessFileDataSink;
  import java.io.OutputStream;
  import java.io.RandomAccessFile;
  import java.security.MessageDigest;
  
  /**
   * Utility methods for working with {@link DataSink} abstraction.
   */
  public abstract class DataSinks {
      private DataSinks() {}
  
      /**
       * Returns a {@link DataSink} which outputs received data into the provided
       * {@link OutputStream}.
       */
      public static DataSink asDataSink(OutputStream out) {
          return new OutputStreamDataSink(out);
      }
  
      /**
       * Returns a {@link DataSink} which outputs received data into the provided file, sequentially,
       * starting at the beginning of the file.
       */
      public static DataSink asDataSink(RandomAccessFile file) {
          return new RandomAccessFileDataSink(file);
      }
  
      /**
       * Returns a {@link DataSink} which forwards data into the provided {@link MessageDigest}
       * instances via their {@code update} method. Each {@code MessageDigest} instance receives the
       * same data.
       */
      public static DataSink asDataSink(MessageDigest... digests) {
          return new MessageDigestSink(digests);
      }
  
      /**
       * Returns a new in-memory {@link DataSink} which exposes all data consumed so far via the
       * {@link DataSource} interface.
       */
      public static ReadableDataSink newInMemoryDataSink() {
          return new ByteArrayDataSink();
      }
  
      /**
       * Returns a new in-memory {@link DataSink} which exposes all data consumed so far via the
       * {@link DataSource} interface.
       *
       * @param initialCapacity initial capacity in bytes
       */
      public static ReadableDataSink newInMemoryDataSink(int initialCapacity) {
          return new ByteArrayDataSink(initialCapacity);
      }
  }
  