/*
   Copyright (c) 2010, 2011, Oracle and/or its affiliates. All rights reserved.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.

   This program is also distributed with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have included with MySQL.

   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 General Public License, version 2.0, for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA
*/

package com.mysql.clusterj.core.store;

import com.mysql.clusterj.ColumnType;

/** Column metadata for ndb columns.
 *
 */
public interface Column {

    /** Get the name of the column.
     * @return the name
     */
    public String getName();

    /** Get the store type of the column.
     * 
     * @return the store type
     */
    public ColumnType getType();

    /** Is this column a primary key column?
     * @return true if this column is a primary key column
     */
    public boolean isPrimaryKey();

    /** Is this column a partition key column?
     * @return true if this column is a partition key column
     */
    public boolean isPartitionKey();

    /** Get the Charset name of the column. This is the value of the 
     * CHARACTER SET parameter in the column definition, or if not specified,
     * the value of the DEFAULT CHARACTER SET parameter in the table definition.
     * 
     * @return the Charset name
     */
    public String getCharsetName();

    /** The charset number.
     * 
     * @return the Charset number
     */
    public int getCharsetNumber();

    /** For character columns, get the maximum length in bytes that can be stored
     * in the column, excluding the prefix, after conversion via the charset.
     */
    public int getLength();

    /** For variable size columns, get the length of the prefix (one or two bytes) 
     * that specifies the length of the column data.
     * @return the prefix length, either one or two bytes for variable sized columns, zero otherwise
     */
    public int getPrefixLength();

    /** The column ID, used for scans to compare column values.
     * 
     * @return the column id
     */
    public int getColumnId();

    /** The space needed to retrieve the value into memory, 
     * including the length byte or bytes at the beginning of the field.
     * 
     * @return the space required by the column
     */
    public int getColumnSpace();

    /** The precision of a decimal column (number of decimal digits before plus after
     * the decimal point).
     * 
     * @return the precision
     */
    public int getPrecision();

    /** The scale of a decimal column (the number of decimal digits after the decimal point).
     * 
     * @return the scale
     */
    public int getScale();

    /** Decode a byte[] into a String using this column's charset.
     * 
     * @param bytes the byte[] from the database
     * @return the decoded String
     */
    public String decode(byte[] bytes);

    /** Encode a String into a byte[] for storage or comparison.
     * 
     * @param string the String
     * @return the encoded byte[]
     */
    public byte[] encode(String string);

    /** Is this column nullable?
     * 
     * @return true if the column is nullable
     */
    public boolean getNullable();

}
