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 * Copyright (c)  2017, 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

package jdk.incubator.sql2;

import java.io.Reader;

import java.io.Writer;

import java.util.concurrent.CompletionStage;

/**

 * A reference to a CHARACTER LARGE OBJECT in the attached database.

 *

 */

public interface SqlClob extends AutoCloseable {

  /**

   * Return an {@link Operation} that will release the temporary resources

   * associated with this {@link SqlClob}.

   *

   * @return an {@link Operation} that will release the temporary resources

   * associated with this {@link SqlClob}.

   */

  public Operation<Void> closeOperation();

  @Override

  public default void close() {

    this.closeOperation().submit();

  }

  /**

   * Return a {@link Operation} that fetches the position of this {@link SqlClob}.

   * Position 0 is immediately before the first char in the {@link SqlClob}.

   * Position 1 is the first char in the {@link SqlClob}, etc. Position

   * {@link length()} is the last char in the {@link SqlClob}.

   *

   * Position is between 0 and length + 1.

   *

   * @return an {@link Operation} that returns the position of this {@link SqlClob}

   * {@link SqlClob} is closed.;

   */

  public Operation<Long> getPositionOperation();

  /**

   * Get the position of this {@link SqlClob}. Position 0 is immediately before the

   * first char in the {@link SqlClob}. Position 1 is the first char in the

   * {@link SqlClob}, etc. Position {@link length()} is the last char in the SqlClob.

 Position is between 0 and length + 1.

 ISSUE: Should position be 1-based as SQL seems to do or 0-based as Java

 does?

   *

   * @return a future which value is the position of this {@link SqlClob}

   * {@link SqlClob} is closed.

   */

  public default CompletionStage<Long> getPosition() {

    return getPositionOperation().submit().getCompletionStage();

  }

  /**

   * Return a {@link Operation} that fetches the length of this {@link SqlClob}.

   *

   * @return a {@link Operation} that returns the length of this {@link SqlClob}

   * {@link SqlClob} is closed.

   */

  public Operation<Long> lengthOperation();

  /**

   * Get the length of this {@link SqlClob}.

   *

   * @return a {@link java.util.concurrent.Future} which value is the number of

   * chars in this {@link SqlClob}

   * {@link SqlClob} is closed.

   */

  public default CompletionStage<Long> length() {

    return lengthOperation().submit().getCompletionStage();

  }

  /**

   * Return an {@link Operation} that sets the position of this {@link SqlClob}. If

   * {@code offset} exceeds the length of this {@link SqlClob} set position to the

   * length + 1 of this {@link SqlClob}, ie one past the last char.

   *

   * @param offset a non-negative number

   * @return a {@link Operation} that sets the position of this {@link SqlClob}

   * @throws IllegalArgumentException if {@code offset} is less than 0

   * {@link SqlClob} is closed.

   */

  public Operation<Long> setPositionOperation(long offset);

  /**

   * Set the position of this {@link SqlClob}. If {@code offset} exceeds the length

   * of this {@link SqlClob} set position to the length + 1 of this {@link SqlClob},

   * ie one past the last char.

   *

   * @param offset the 1-based position to set

   * @return this {@link SqlClob}

   * @throws IllegalArgumentException if {@code offset} is less than 0

   * {@link SqlClob} is closed.

   */

  public default SqlClob setPosition(long offset) {

    setPositionOperation(offset).submit();

    return this;

  }

  /**

   * Return an {@link Operation} to set the position to the beginning of the

   * next occurrence of the target after the position. If there is no such

   * occurrence set the position to 0.

   *

   * containing the char sequence to search for

   * @return an {@link Operation} that locates {@code target} in this

   * {@link SqlClob}

   * @throws IllegalArgumentException if {@code target} was created by some

   * {@link SqlClob} is closed.

   */

  public Operation<Long> locateOperation(SqlClob target);

  /**

   * Set the position to the beginning of the next occurrence of the target

   * after the position. If there is no such occurrence set the position to 0.

   *

   * @param target the char sequence to search for

   * @return this {@link SqlClob}

   * @throws IllegalArgumentException if {@code target} was created by some

   * {@link SqlClob} is closed

   */

  public default SqlClob locate(SqlClob target) {

    locateOperation(target).submit();

    return this;

  }

  /**

   * Return an {@link Operation} to set the position to the beginning of the

   * next occurrence of the target after the position. If there is no such

   * occurrence set the position to 0.

   *

   * @param target the char sequence to search for. Not {@code null}. Captured.

   * @return an {@link Operation} that locates {@code target} in this

   * {@link SqlClob}

   * {@link SqlClob} is closed.

   */

  public Operation<Long> locateOperation(CharSequence target);

  /**

   * Set the position to the beginning of the next occurrence of the target

   * after the position. If there is no such occurrence set the position to 0.

   *

   * @param target the char sequence to search for

   * @return this {@link SqlClob}

   * {@link SqlClob} is closed.

   */

  public default SqlClob locate(CharSequence target) {

    locateOperation(target).submit();

    return this;

  }

  /**

   * Return an {@link Operation} that truncates this {@link SqlClob} so that the

   * current position is the end of the {@link SqlClob}. If the position is N, then

   * after trim() the length is N - 1. The position is still N. This will fail

   * if position is 0.

   *

   * @return an {@link Operation} that trims the length of this {@link SqlClob}

   * {@link SqlClob} is closed or position is 0.

   */

  public Operation<Long> trimOperation();

  /**

   * Truncate this {@link SqlClob} so that the current position is the end of the

   * {@link SqlClob}. If the position is N, then after {@link trim()} the length is

   * N - 1. The position is still N. This will fail if position is 0.

   *

   * @return this {@link SqlClob}

   * {@link SqlClob} is closed or position is 0.

   */

  public default SqlClob trim() {

    trimOperation().submit();

    return this;

  }

  /**

   * Returns a {@link Reader} for the characters in this {@link SqlClob}.

   * Characters are read starting at the current position. Each character read

   * advances the position by one.

   *

   * ISSUE: There is no character analog to

   * {@link java.nio.channels.AsynchronousByteChannel}. It is trivial to

   * construct a {@link java.io.Reader} from an

   * {@link java.nio.channels.AsynchronousByteChannel} however.

   *

   * @return a Reader for the characters in this SqlClob

   */

  public Reader getReader();

  /**

   * Returns a Writer for this {@link SqlClob}. Characters are written starting at

   * the current position. Each character written advances the position by one.

   *

   * ISSUE: There is no character analog to

   * {@link java.nio.channels.AsynchronousByteChannel}. It is trivial to

   * construct a {@link java.io.Writer} from an

   * {@link java.nio.channels.AsynchronousByteChannel} however.

   *

   * @return a Writer for the characters of this SqlClob

   */

  public Writer getWriter();

}