| /* |
| * 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.iotdb.db.queryengine.plan.planner.plan.node.process; |
| |
| import org.apache.iotdb.db.queryengine.plan.planner.plan.node.PlanNode; |
| import org.apache.iotdb.db.queryengine.plan.planner.plan.node.PlanNodeId; |
| import org.apache.iotdb.db.queryengine.plan.planner.plan.node.PlanNodeType; |
| import org.apache.iotdb.db.queryengine.plan.planner.plan.node.PlanVisitor; |
| |
| import org.apache.tsfile.utils.ReadWriteIOUtils; |
| |
| import java.io.DataOutputStream; |
| import java.io.IOException; |
| import java.nio.ByteBuffer; |
| import java.util.List; |
| import java.util.Objects; |
| |
| /** |
| * OffsetNode is used to skip top n result from upstream nodes. It uses the default order of |
| * upstream nodes |
| */ |
| public class OffsetNode extends SingleChildProcessNode { |
| |
| private final long offset; |
| |
| public OffsetNode(PlanNodeId id, long offset) { |
| super(id); |
| this.offset = offset; |
| } |
| |
| public OffsetNode(PlanNodeId id, PlanNode child, long offset) { |
| super(id, child); |
| this.offset = offset; |
| } |
| |
| @Override |
| public PlanNodeType getType() { |
| return PlanNodeType.OFFSET; |
| } |
| |
| @Override |
| public PlanNode clone() { |
| return new OffsetNode(getPlanNodeId(), offset); |
| } |
| |
| @Override |
| public List<String> getOutputColumnNames() { |
| return child.getOutputColumnNames(); |
| } |
| |
| @Override |
| public <R, C> R accept(PlanVisitor<R, C> visitor, C context) { |
| return visitor.visitOffset(this, context); |
| } |
| |
| @Override |
| protected void serializeAttributes(ByteBuffer byteBuffer) { |
| PlanNodeType.OFFSET.serialize(byteBuffer); |
| ReadWriteIOUtils.write(offset, byteBuffer); |
| } |
| |
| @Override |
| protected void serializeAttributes(DataOutputStream stream) throws IOException { |
| PlanNodeType.OFFSET.serialize(stream); |
| ReadWriteIOUtils.write(offset, stream); |
| } |
| |
| public static OffsetNode deserialize(ByteBuffer byteBuffer) { |
| long offset = ReadWriteIOUtils.readLong(byteBuffer); |
| PlanNodeId planNodeId = PlanNodeId.deserialize(byteBuffer); |
| return new OffsetNode(planNodeId, offset); |
| } |
| |
| public long getOffset() { |
| return offset; |
| } |
| |
| @Override |
| public String toString() { |
| return "OffsetNode-" + this.getPlanNodeId(); |
| } |
| |
| @Override |
| public boolean equals(Object o) { |
| if (this == o) { |
| return true; |
| } |
| if (o == null || getClass() != o.getClass()) { |
| return false; |
| } |
| if (!super.equals(o)) { |
| return false; |
| } |
| OffsetNode that = (OffsetNode) o; |
| return offset == that.offset; |
| } |
| |
| @Override |
| public int hashCode() { |
| return Objects.hash(super.hashCode(), offset); |
| } |
| } |