LazyInitReaderReleaseShim.java

/*
 * stringhold
 *
 * Copyright 2022-2024 Christian Kohlschütter
 *
 * 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.kohlschutter.stringhold;

import java.io.IOException;
import java.io.Reader;
import java.io.Writer;

abstract class LazyInitReaderReleaseShim extends Reader {
  protected abstract class KickstartPlaceholderReleaseShim extends Reader {

    @Override
    public long transferTo(Writer out) throws IOException {
      return init().transferTo(out);
    }
  }

  @Override
  public long transferTo(Writer out) throws IOException {
    return currentReader().transferTo(out);
  }

  abstract Reader currentReader();

  abstract Reader init() throws IOException;
}