/**
* Copyright 2011-2013 FoundationDB, LLC
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* The original from which this derives bore the following: */
/*
Derby - Class org.apache.derby.impl.sql.compile.UserTypeConstantNode
Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements. See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to you under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package com.foundationdb.sql.parser;
import com.foundationdb.sql.StandardException;
import com.foundationdb.sql.types.DataTypeDescriptor;
import com.foundationdb.sql.types.TypeId;
import java.sql.Date;
import java.sql.Time;
import java.sql.Timestamp;
import java.sql.Types;
/**
User type constants. These are created by built-in types
that use user types as their implementation. This could also
potentially be used by an optimizer that wanted to store plans
for frequently-used parameter values.
This is also used to represent nulls in user types, which occurs
when NULL is inserted into or supplied as the update value for
a usertype column.
*/
public class UserTypeConstantNode extends ConstantNode
{
/*
** This value field hides the value in the super-type. It is here
** Because user-type constants work differently from built-in constants.
** User-type constant values are stored as Objects, while built-in
** constants are stored as StorableDataValues.
**
** RESOLVE: This is a bit of a mess, and should be fixed. All constants
** should be represented the same way.
*/
Object value;
/**
* Initializer for a typed null node
* or a date, time, or timestamp value. Parameters may be:
*
* <ul>
* <li>arg1 The TypeId for the type of the node</li>
* </ul>
*
* <p>
* - OR -
* </p>
*
* <ul>
* <li>arg1 the date, time, or timestamp value</li>
* </ul>
*
* @exception StandardException thrown on failure
*/
public void init(Object arg1) throws StandardException {
if (arg1 instanceof TypeId) {
super.init(arg1,
Boolean.TRUE,
DataTypeDescriptor.MAXIMUM_WIDTH_UNKNOWN);
}
else {
Integer maxWidth = null;
TypeId typeId = null;
if (arg1 instanceof Date) {
maxWidth = TypeId.DATE_MAXWIDTH;
typeId = TypeId.getBuiltInTypeId(Types.DATE);
}
else if (arg1 instanceof Time) {
maxWidth = TypeId.TIME_MAXWIDTH;
typeId = TypeId.getBuiltInTypeId(Types.TIME);
}
else if (arg1 instanceof Timestamp) {
maxWidth = TypeId.TIMESTAMP_MAXWIDTH;
typeId = TypeId.getBuiltInTypeId(Types.TIMESTAMP);
}
else {
assert false : "Unexpected class " + arg1.getClass().getName();
}
super.init(typeId,
(arg1 == null) ? Boolean.TRUE : Boolean.FALSE,
maxWidth);
// TODO: For now, these are the same.
setValue(arg1);
value = arg1;
}
}
/**
* Fill this node with a deep copy of the given node.
*/
public void copyFrom(QueryTreeNode node) throws StandardException {
super.copyFrom(node);
UserTypeConstantNode other = (UserTypeConstantNode)node;
this.value = other.value;
}
/**
* Return the object value of this user defined type.
*
* @return the value of this constant. can't use getValue() for this.
* getValue() returns the DataValueDescriptor for the built-in
* types that are implemented as user types (date, time, timestamp)
*/
public Object getObjectValue() {
return value;
}
/**
* Return whether or not this node represents a typed null constant.
*
*/
public boolean isNull() {
return (value == null);
}
/**
* Return an Object representing the bind time value of this
* expression tree. If the expression tree does not evaluate to
* a constant at bind time then we return null.
* This is useful for bind time resolution of VTIs.
* RESOLVE: What do we do for primitives?
*
* @return An Object representing the bind time value of this expression tree.
* (null if not a bind time constant.)
*
*/
public Object getConstantValueAsObject() {
return value;
}
}