/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.fory.io;

import java.nio.ByteBuffer;
import java.nio.channels.WritableByteChannel;

/**
 * A helper class to track the size of allocations. Writes to this stream do not copy or retain any
 * data, they just bump a size counter that can be later used to know exactly which data size needs
 * to be allocated for actual writing.
 */
public class MockWritableChannel implements WritableByteChannel {
  private boolean open = true;
  private int totalBytes;

  @Override
  public int write(ByteBuffer src) {
    int remaining = src.remaining();
    src.position(src.limit());
    totalBytes += remaining;
    return remaining;
  }

  public int totalBytes() {
    return totalBytes;
  }

  @Override
  public boolean isOpen() {
    return open;
  }

  @Override
  public void close() {
    open = false;
  }
}
