DataHandler.java
/*
** Module : DataHandler.java
** Abstract : Groups together Converter and ParameterSetter functional interfaces.
**
** Copyright (c) 2019-2024, Golden Code Development Corporation.
**
** -#- -I- --Date-- ---------------------------------Description---------------------------------
** 001 OM 20191101 Created initial version.
** 002 TJD 20240123 Java 17 compatibility updates
*/
/*
** 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.types;
import com.goldencode.p2j.persist.Record;
import com.goldencode.p2j.persist.orm.*;
import com.goldencode.p2j.util.*;
/**
* Groups together {@code PropertyReader}, {@code ParameterSetter}, and {@code InitialValueFactory}
* functional interfaces. This forces implementing classes to write the conversion between/from
* SQL supported values and {@code BaseDataType} in the same location, as well as an interpreter
* for legacy initial value strings.
*/
public interface DataHandler
extends ParameterSetter,
PropertyReader
{
/**
* Instantiate a low-level initial value suitable for storage in a {@link BaseRecord}'s data
* array, parsed from a string representation.
*
* @param text
* String representation of the initial value.
* @param meta
* Property metadata.
*
* @throws UnsupportedOperationException
* in the default implementation. All concrete, leaf, base data types which can be the
* actual data type of a converted record field must override this implementation.
*/
public default Object initialValue(String text, PropertyMeta meta)
{
throw new UnsupportedOperationException(
"Method initialValue() not implemented for " + this.getClass());
}
/**
* Converts to and returns a {@code BaseDataType} from a SQL value.
*
* @param sqlVal
* A value obtained from a SQL query, which needs to be converted to a
* {@code BaseDataType}.
*
* @return a specific {@code BaseDataType}, or {@code null} if conversion is not possible.
*/
public default BaseDataType convert(Object sqlVal)
{
throw new UnsupportedOperationException(
"Method convert() not implemented for " + this.getClass());
}
/**
* Compute the size in bytes taken by a specified value for the data type handled by this
* class. The returned value is used to compute the index size.
*
* @param val
* The value to be computed the size.
*
* @return the number of bytes the {@code val} object occupies.
*/
public default int getFieldSizeInIndex(Object val)
{
throw new UnsupportedOperationException(
"Method computeFieldSize() not implemented for " + this.getClass());
}
/**
* Sets a value of a property in a {@code Record}. The specified value is converted from
* {@code BaseDataType} FWD standard to plain Java, as the {@code data} array expects before
* assigning the value to right offset.
*
* @param data
* The {@code data} array of the record to be altered.
* @param val
* The {@code BaseDataType} value to be set.
* @param offset
* The offset of the property, ie, the entry in {@code data} array. This includes both
* base property offset and the eventual extent index.
* @param meta
* Property metadata. Used to fine-tune stored data.
*/
public void setField(Object[] data, BaseDataType val, int offset, PropertyMeta meta);
/**
* Obtain the value of the property of a {@code Record} located at a specified offset in {@code data}
* array. It assumes the data at specified offset is compatible with this data handler.
*
* @param r
* The {@code Record}.
* @param offset
* The offset.
*
* @return The value requested wrapped as a {@code BaseDataType}.
*/
public BaseDataType getField(Record r, int offset);
}