/* Copyright (c) 2001-2011, The HSQL Development Group
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of the HSQL Development Group nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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package org.hsqldb.types;
import org.hsqldb.
Session;
import org.hsqldb.
SessionInterface;
import org.hsqldb.
Tokens;
import org.hsqldb.error.
Error;
import org.hsqldb.error.
ErrorCode;
/**
* Type subclass for untyped NULL values.<p>
*
* @author Fred Toussi (fredt@users dot sourceforge.net)
* @version 2.3.1
* @since 1.9.0
*/
public final class
NullType extends
Type {
static final
NullType nullType = new
NullType();
private
NullType() {
super(
Types.
SQL_ALL_TYPES,
Types.
SQL_ALL_TYPES, 0, 0);
}
public int
displaySize() {
return 4;
}
public int
getJDBCTypeCode() {
return
typeCode;
}
public
Class getJDBCClass() {
return java.lang.
Void.class;
}
public
String getJDBCClassName() {
return "java.lang.Void";
}
public
String getNameString() {
return
Tokens.
T_NULL;
}
public
String getDefinition() {
return
Tokens.
T_NULL;
}
public
Type getAggregateType(
Type other) {
return
other;
}
public
Type getCombinedType(
Session session,
Type other, int
operation) {
return
other;
}
public int
compare(
Session session,
Object a,
Object b) {
throw
Error.
runtimeError(
ErrorCode.
U_S0500, "NullType");
}
public
Object convertToTypeLimits(
SessionInterface session,
Object a) {
return null;
}
public
Object convertToType(
SessionInterface session,
Object a,
Type otherType) {
return null;
}
public
Object convertToDefaultType(
SessionInterface session,
Object a) {
return null;
}
public
String convertToString(
Object a) {
return
Tokens.
T_NULL;
}
public
String convertToSQLString(
Object a) {
return
Tokens.
T_NULL;
}
public boolean
canConvertFrom(
Type otherType) {
return true;
}
public static
Type getNullType() {
return
nullType;
}
}