/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* License: GNU Lesser General Public License (LGPL), version 2.1 or later.
* See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
*/
package org.hibernate;
/**
* Defines precedence of null values within {@code ORDER BY} clause.
*
* @author Lukasz Antoniak (lukasz dot antoniak at gmail dot com)
*/
public enum NullPrecedence {
/**
* Null precedence not specified. Relies on the RDBMS implementation.
*/
NONE,
/**
* Null values appear at the beginning of the sorted collection.
*/
FIRST,
/**
* Null values appear at the end of the sorted collection.
*/
LAST;
/**
* Interprets a string representation of a NullPrecedence, returning {@code null} by default. For
* alternative default handling, see {@link #parse(String, NullPrecedence)}
*
* @param name The String representation to interpret
*
* @return The recognized NullPrecedence, or {@code null}
*/
public static NullPrecedence parse(String name) {
if ( "none".equalsIgnoreCase( name ) ) {
return NullPrecedence.NONE;
}
else if ( "first".equalsIgnoreCase( name ) ) {
return NullPrecedence.FIRST;
}
else if ( "last".equalsIgnoreCase( name ) ) {
return NullPrecedence.LAST;
}
return null;
}
/**
* Interprets a string representation of a NullPrecedence, returning the specified default if not recognized.
*
* @param name The String representation to interpret
* @param defaultValue The default value to use
*
* @return The recognized NullPrecedence, or {@code defaultValue}.
*/
public static NullPrecedence parse(String name, NullPrecedence defaultValue) {
final NullPrecedence value = parse( name );
return value != null ? value : defaultValue;
}
}