io.trino.sql.planner.SubExpressionExtractor Maven / Gradle / Ivy
/*
* 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.
*/
package io.trino.sql.planner;
import io.trino.sql.tree.Expression;
import io.trino.sql.util.AstUtils;
import java.util.stream.Stream;
/**
* Extracts and returns the stream of all expression subtrees within an Expression, including Expression itself
*/
public final class SubExpressionExtractor
{
private SubExpressionExtractor() {}
public static Stream extract(Expression expression)
{
return AstUtils.preOrder(expression)
.filter(Expression.class::isInstance)
.map(Expression.class::cast);
}
}