content: /*
   * 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.beam.sdk.coders;
  
  import java.io.Serializable;
  import java.util.Collections;
  import java.util.List;
  
  /**
   * An abstract base class that implements all methods of {@link Coder} except {@link Coder#encode}
   * and {@link Coder#decode}.
   *
   * @param <T> the type of values being encoded and decoded
   */
  public abstract class CustomCoder<T> extends Coder<T> implements Serializable {
  
    /**
     * {@inheritDoc}.
     *
     * <p>Returns an empty list. A {@link CustomCoder} has no default argument {@link Coder coders}.
     */
    @Override
    public List<? extends Coder<?>> getCoderArguments() {
      return Collections.emptyList();
    }
  
    /**
     * {@inheritDoc}
     *
     * @throws NonDeterministicException a {@link CustomCoder} is presumed nondeterministic.
     */
    @Override
    public void verifyDeterministic() throws NonDeterministicException {
      throw new NonDeterministicException(
          this,
          "CustomCoder implementations must override verifyDeterministic,"
              + " or they are presumed nondeterministic.");
    }
  
    // This coder inherits isRegisterByteSizeObserverCheap,
    // getEncodedElementByteSize and registerByteSizeObserver
    // from Coder. Override if we can do better.
  }
  