com.hazelcast.org.apache.calcite.linq4j.tree.Expression 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.linq4j.tree;
import java.lang.reflect.Type;
/**
* Analogous to LINQ's System.Linq.Expression.
*/
public abstract class Expression extends AbstractNode {
/**
* Creates an Expression.
*
* The type of the expression may, at the caller's discretion, be a
* regular class (because {@link Class} implements {@link Type}) or it may
* be a different implementation that retains information about type
* parameters.
*
* @param nodeType Node type
* @param type Type of the expression
*/
protected Expression(ExpressionType nodeType, Type type) {
super(nodeType, type);
assert nodeType != null;
assert type != null;
}
@Override // More specific return type.
public abstract Expression accept(Shuttle shuttle);
/**
* Indicates that the node can be reduced to a simpler node. If this
* returns true, Reduce() can be called to produce the reduced form.
*/
public boolean canReduce() {
return false;
}
}