com.hazelcast.org.apache.calcite.rex.RexWindowBound Maven / Gradle / Ivy
/*
* 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.hazelcast.org.apache.calcite.rex;
import com.hazelcast.org.apache.calcite.sql.SqlNode;
/**
* Abstracts "XX PRECEDING/FOLLOWING" and "CURRENT ROW" bounds for windowed
* aggregates.
*
* @see RexWindowBounds
*/
public abstract class RexWindowBound {
/** Use {@link RexWindowBounds#create(SqlNode, RexNode)}. */
@Deprecated // to be removed before 2.0
public static RexWindowBound create(SqlNode node, RexNode rexNode) {
return RexWindowBounds.create(node, rexNode);
}
/**
* Returns if the bound is unbounded.
* @return if the bound is unbounded
*/
public boolean isUnbounded() {
return false;
}
/**
* Returns if the bound is PRECEDING.
* @return if the bound is PRECEDING
*/
public boolean isPreceding() {
return false;
}
/**
* Returns if the bound is FOLLOWING.
* @return if the bound is FOLLOWING
*/
public boolean isFollowing() {
return false;
}
/**
* Returns if the bound is CURRENT ROW.
* @return if the bound is CURRENT ROW
*/
public boolean isCurrentRow() {
return false;
}
/**
* Returns offset from XX PRECEDING/FOLLOWING.
*
* @return offset from XX PRECEDING/FOLLOWING
*/
public RexNode getOffset() {
return null;
}
/**
* Returns relative sort offset when known at compile time.
* For instance, UNBOUNDED PRECEDING is less than CURRENT ROW.
*
* @return relative order or -1 when order is not known
*/
public int getOrderKey() {
return -1;
}
/**
* Transforms the bound via {@link com.hazelcast.org.apache.calcite.rex.RexVisitor}.
* @param visitor visitor to accept
* @param return type of the visitor
* @return transformed bound
*/
public RexWindowBound accept(RexVisitor visitor) {
return this;
}
/**
* Returns the number of nodes in this bound.
*
* @see RexNode#nodeCount()
*/
public int nodeCount() {
return 1;
}
}