| /* |
| * 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.Collections; |
| import java.util.List; |
| |
| import org.apache.phoenix.compile.ColumnResolver; |
| |
| |
| |
| /** |
| * |
| * Node representing the IS NULL and IS NOT NULL expressions in SQL |
| * |
| * |
| * @since 0.1 |
| */ |
| public class IsNullParseNode extends UnaryParseNode { |
| private final boolean negate; |
| |
| IsNullParseNode(ParseNode expr, boolean negate) { |
| super(expr); |
| this.negate = negate; |
| } |
| |
| public boolean isNegate() { |
| return negate; |
| } |
| |
| @Override |
| public <T> T accept(ParseNodeVisitor<T> visitor) throws SQLException { |
| List<T> l = Collections.emptyList(); |
| if (visitor.visitEnter(this)) { |
| l = acceptChildren(visitor); |
| } |
| return visitor.visitLeave(this, l); |
| } |
| |
| @Override |
| public int hashCode() { |
| final int prime = 31; |
| int result = super.hashCode(); |
| result = prime * result + (negate ? 1231 : 1237); |
| return result; |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (this == obj) |
| return true; |
| if (!super.equals(obj)) |
| return false; |
| if (getClass() != obj.getClass()) |
| return false; |
| IsNullParseNode other = (IsNullParseNode) obj; |
| if (negate != other.negate) |
| return false; |
| return true; |
| } |
| |
| @Override |
| public void toSQL(ColumnResolver resolver, StringBuilder buf) { |
| getChildren().get(0).toSQL(resolver, buf); |
| buf.append(" IS"); |
| if (negate) buf.append(" NOT"); |
| buf.append(" NULL "); |
| } |
| } |