# RowStructure.java

    /*
    ** Module   : RowStructure.java
    ** Abstract : Defines a row structure in a query.
    **
    ** Copyright (c) 2020-2023, Golden Code Development Corporation.
    **
    ** -#- -I- --Date-- ----------------------------------------Description---------------------------------------
    ** 001 CA  20200615 Created initial version.
    ** 002 SBI 20221031 Added a "fields" member. It is used as a storage of fields of "select" query.
    ** 003 AL2 20231123 Refactored this as an interface. Moved implementation in AbstractRowStructure.
    **     AL2 20231211 Added getDmoMeta.
    */

    /*
    ** This program is free software: you can redistribute it and/or modify
    ** it under the terms of the GNU Affero General Public License as
    ** published by the Free Software Foundation, either version 3 of the
    ** License, or (at your option) any later version.
    **
    ** This program 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 Affero General Public License for more details.
    **
    ** You may find a copy of the GNU Affero GPL version 3 at the following
    ** location: https://www.gnu.org/licenses/agpl-3.0.en.html
    **
    ** Additional terms under GNU Affero GPL version 3 section 7:
    **
    **   Under Section 7 of the GNU Affero GPL version 3, the following additional
    **   terms apply to the works covered under the License.  These additional terms
    **   are non-permissive additional terms allowed under Section 7 of the GNU
    **   Affero GPL version 3 and may not be removed by you.
    **
    **   0. Attribution Requirement.
    **
    **     You must preserve all legal notices or author attributions in the covered
    **     work or Appropriate Legal Notices displayed by works containing the covered
    **     work.  You may not remove from the covered work any author or developer
    **     credit already included within the covered work.
    **
    **   1. No License To Use Trademarks.
    **
    **     This license does not grant any license or rights to use the trademarks
    **     Golden Code, FWD, any Golden Code or FWD logo, or any other trademarks
    **     of Golden Code Development Corporation. You are not authorized to use the
    **     name Golden Code, FWD, or the names of any author or contributor, for
    **     publicity purposes without written authorization.
    **
    **   2. No Misrepresentation of Affiliation.
    **
    **     You may not represent yourself as Golden Code Development Corporation or FWD.
    **
    **     You may not represent yourself for publicity purposes as associated with
    **     Golden Code Development Corporation, FWD, or any author or contributor to
    **     the covered work, without written authorization.
    **
    **   3. No Misrepresentation of Source or Origin.
    **
    **     You may not represent the covered work as solely your work.  All modified
    **     versions of the covered work must be marked in a reasonable way to make it
    **     clear that the modified work is not originating from Golden Code Development
    **     Corporation or FWD.  All modified versions must contain the notices of
    **     attribution required in this license.
    */

    package com.goldencode.p2j.persist.orm;

    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.util.Iterator;

    import com.goldencode.p2j.persist.DataModelObject;
    import com.goldencode.p2j.persist.PersistenceException;

    /**
     * Defines a row structure in a SELECT query. There are multiplex flavors of such structure, most of them
     * attempting to optimize the hydration or representation of selected fields. Refer to
     * {@link FullRowStructure} for an example of structure that represents the "select all" attempt.
     *
     * Non-expanded properties are logically part of this structure, but will only affect the {@link #hasExtents()}
     * flag. In other words, non-expanded properties will be hydrated only if a non-expanded property is appended,
     * making {@link #hasExtents()} return true (or use {@link #forceExtents}.
     * Otherwise, non-expanded extents won't be hydrated.
     */
    public interface RowStructure
    {
       /**
        * The DMO class whose properties are included in this structure.
        *
        * @return   The DMO class underlying this structure.
        */
       public Class<? extends DataModelObject> getDmoClass();

       /**
        * Append the recid to the row structure.
        *
        * @param   recid
        *          The recid property to be appended to the structure.
        *
        * @return  {@code true} if adding the recid to the row structure succeeded
        *          If there is some invariant on the structure, adding props may fail.
        */
       public boolean addRecid(Property recid);

       /**
        * Append the multiplex to the row structure.
        *
        * @param   multiplex
        *          The multiplex property to be appended to the structure.
        *
        * @return  {@code true} if adding the multiplex to the row structure succeeded
        *          If there is some invariant on the structure, adding props may fail.
        */
       public boolean addMultiplex(Property multiplex);

       /**
        * Append a property to the row structure. This doesn't check if the property actually belongs to the
        * DMO class used for this structure.
        *
        * @param   prop
        *          The property to be appended to the structure.
        *
        * @return  {@code true} if adding the prop to the row structure succeeded
        *          If there is some invariant on the structure, adding props may fail.
        */
       public boolean addProperty(Property prop);

       /**
        * Retrieve the number of SQL fields that will be interpreted by this row structure. This is not the
        * same as the number of properties (e.g. datetime-tz consumes 2 SQL columns)
        *
        * @return   The number of SQL fields that are covered by this row structure.
        */
       public int getCount();

       /**
        * Retrieve an iterator to all properties in this structure, including the recid and multiplex.
        *
        * @return   An iterator to all properties in this structure, in order of their append.
        */
       public Iterator<Property> getProps();

       /**
        * Check if this structure requires a hydration of non-expanded extent properties. This will only return true
        * if a non-expanded extent property was ever added through {@link #addProperty}  or {@link #forceExtents()} was
        * called.
        *
        * @return   {@code true} if this structure will also hydrate non-expanded properties.
        */
       public boolean hasExtents();

       /**
        * Force the non-expanded extents to be hydrated.
        */
       public void forceExtents();

       /**
        * The core hydration logic based on the row structure. This class is specialized in traversing the
        * result-set and populating the record with the data found there.
        *
        * @param   session
        *          The underlying session that generated the result-set. It is used only to emit
        *          load SQLs for the non-expanded extents. If this is {@code null}, the non-expanded
        *          extents will be skipped.
        * @param   resultSet
        *          The result-set that provides the low-level data that should be hydrated into
        *          the record.
        * @param   rsOffset
        *          The offset where the DMO starts. This is the case for queries that had joins,
        *          so the current record may not start at index 1.
        * @param   r
        *          The record to be hydrated.
        *
        * @return  The next rsOffset, from where the next DMO in the result-set will start (if any).
        *
        * @throws  PersistenceException
        *          thrown when hydrating extents fails (as it requires extra SQL queries to be run).
        * @throws  SQLException
        *          throw when failing to hydrate from the result-set.
        */
       public int hydrate(Session session, ResultSet resultSet, int rsOffset, BaseRecord r)
       throws PersistenceException,
              SQLException;

       /**
        * Retrieve the DMO meta used by the underlying DMO of this structure.
        *
        * @return   The DMO meta of the DMO used by this row structure
        */
       public DmoMeta getDmoMeta();

       /**
        * Check if the structure is incomplete. Most implementations are hydrate the record partially,
        * except for {@link FullRowStructure}.
        *
        * @return   {@code true} by default.
        */
       public default boolean isIncomplete()
       {
          return true;
       }
    }