| /* |
| * 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 org.apache.phoenix.parse; |
| |
| import java.sql.SQLException; |
| import java.util.List; |
| |
| import org.apache.phoenix.compile.ColumnResolver; |
| |
| |
| |
| |
| /** |
| * |
| * Abstract base class for a parse node in SQL |
| * |
| * |
| * @since 0.1 |
| */ |
| public abstract class ParseNode { |
| public abstract List<ParseNode> getChildren(); |
| public abstract <T> T accept(ParseNodeVisitor<T> visitor) throws SQLException; |
| |
| public boolean isStateless() { |
| return false; |
| } |
| |
| /** |
| * Allows node to override what the alias is for a given node. |
| * Useful for a column reference, as JDBC says that the alias |
| * name for "a.b" should be "b" |
| * @return the alias to use for this node or null for no alias |
| */ |
| public String getAlias() { |
| return null; |
| } |
| |
| @Override |
| public final String toString() { |
| StringBuilder buf = new StringBuilder(); |
| toSQL(null, buf); |
| return buf.toString(); |
| } |
| |
| public abstract void toSQL(ColumnResolver resolver, StringBuilder buf); |
| } |