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/*
 * Copyright 2017-2024 O2 Czech Republic, a.s.
 *
 * 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 cz.o2.proxima.direct.io.cassandra;

import java.io.Serializable;
import java.nio.charset.StandardCharsets;
import javax.annotation.Nullable;
import javax.annotation.concurrent.ThreadSafe;

/** A converter between a specified java type and {@code String}. */
@ThreadSafe
public interface StringConverter extends Serializable {

  class DefaultConverter implements StringConverter {

    private static final long serialVersionUID = 1L;

    /** String value that all strings should be less than. */
    static final String MAX = new String(new byte[] {(byte) 0xFF}, 0, 1, StandardCharsets.US_ASCII);

    /** String value that all strings should be greater or equal to. */
    static final String MIN = "";

    @Override
    public String asString(String what) {
      return what;
    }

    @Override
    public @Nullable String fromString(String what) {
      return what;
    }

    @Override
    public String max() {
      return MAX;
    }

    @Override
    public String min() {
      return MIN;
    }
  }

  static StringConverter getDefault() {
    return new DefaultConverter();
  }

  /**
   * Convert type to string.
   *
   * @param what input type
   * @return string representation of what
   */
  String asString(T what);

  /**
   * Convert type from string.
   *
   * @param what string representation
   * @return the original object
   */
  T fromString(String what);

  /**
   * Retrieve maximal element.
   *
   * @return instance of maximal object
   */
  T max();

  /**
   * Retrieve minimal element
   *
   * @return instance of minimal object
   */
  T min();
}