| /* |
| * 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.execution.operator.schema; |
| |
| import org.apache.iotdb.commons.exception.runtime.SchemaExecutionException; |
| import org.apache.iotdb.db.queryengine.execution.driver.SchemaDriverContext; |
| import org.apache.iotdb.db.queryengine.execution.operator.OperatorContext; |
| import org.apache.iotdb.db.queryengine.execution.operator.schema.source.ISchemaSource; |
| import org.apache.iotdb.db.queryengine.execution.operator.source.SourceOperator; |
| import org.apache.iotdb.db.queryengine.plan.planner.plan.node.PlanNodeId; |
| import org.apache.iotdb.db.schemaengine.schemaregion.ISchemaRegion; |
| import org.apache.iotdb.db.schemaengine.schemaregion.read.resp.info.ISchemaInfo; |
| import org.apache.iotdb.db.schemaengine.schemaregion.read.resp.reader.ISchemaReader; |
| import org.apache.iotdb.tsfile.file.metadata.enums.TSDataType; |
| import org.apache.iotdb.tsfile.read.common.block.TsBlock; |
| import org.apache.iotdb.tsfile.read.common.block.TsBlockBuilder; |
| |
| import com.google.common.util.concurrent.ListenableFuture; |
| |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.NoSuchElementException; |
| |
| public class SchemaCountOperator<T extends ISchemaInfo> implements SourceOperator { |
| |
| private static final List<TSDataType> OUTPUT_DATA_TYPES = |
| Collections.singletonList(TSDataType.INT64); |
| |
| private final PlanNodeId sourceId; |
| private final OperatorContext operatorContext; |
| |
| private final ISchemaSource<T> schemaSource; |
| |
| private ISchemaReader<T> schemaReader; |
| private int count; |
| private boolean isFinished; |
| private ListenableFuture<?> isBlocked; |
| private TsBlock next; // next will be set only when done |
| |
| public SchemaCountOperator( |
| PlanNodeId sourceId, OperatorContext operatorContext, ISchemaSource<T> schemaSource) { |
| this.sourceId = sourceId; |
| this.operatorContext = operatorContext; |
| this.schemaSource = schemaSource; |
| } |
| |
| private ISchemaRegion getSchemaRegion() { |
| return ((SchemaDriverContext) operatorContext.getDriverContext()).getSchemaRegion(); |
| } |
| |
| private ISchemaReader<T> createSchemaReader() { |
| return schemaSource.getSchemaReader(getSchemaRegion()); |
| } |
| |
| @Override |
| public OperatorContext getOperatorContext() { |
| return operatorContext; |
| } |
| |
| @Override |
| public ListenableFuture<?> isBlocked() { |
| if (isBlocked == null) { |
| isBlocked = tryGetNext(); |
| } |
| return isBlocked; |
| } |
| |
| /** |
| * Try to get next TsBlock. If the next is not ready, return a future. After success, {@link |
| * SchemaCountOperator#next} will be set. |
| */ |
| private ListenableFuture<?> tryGetNext() { |
| ISchemaRegion schemaRegion = getSchemaRegion(); |
| if (schemaSource.hasSchemaStatistic(schemaRegion)) { |
| next = constructTsBlock(schemaSource.getSchemaStatistic(schemaRegion)); |
| return NOT_BLOCKED; |
| } else { |
| if (schemaReader == null) { |
| schemaReader = createSchemaReader(); |
| } |
| while (true) { |
| try { |
| ListenableFuture<?> readerBlocked = schemaReader.isBlocked(); |
| if (!readerBlocked.isDone()) { |
| return readerBlocked; |
| } else if (schemaReader.hasNext()) { |
| schemaReader.next(); |
| count++; |
| } else { |
| next = constructTsBlock(count); |
| return NOT_BLOCKED; |
| } |
| } catch (Exception e) { |
| throw new SchemaExecutionException(e); |
| } |
| } |
| } |
| } |
| |
| @Override |
| public TsBlock next() throws Exception { |
| if (!hasNext()) { |
| throw new NoSuchElementException(); |
| } |
| if (next != null) { |
| isFinished = true; |
| } |
| isBlocked = null; |
| return next; |
| } |
| |
| @Override |
| public boolean hasNext() throws Exception { |
| isBlocked().get(); // wait for the next TsBlock |
| if (schemaReader != null && !schemaReader.isSuccess()) { |
| throw new SchemaExecutionException(schemaReader.getFailure()); |
| } |
| return !isFinished; |
| } |
| |
| private TsBlock constructTsBlock(long count) { |
| TsBlockBuilder tsBlockBuilder = new TsBlockBuilder(OUTPUT_DATA_TYPES); |
| tsBlockBuilder.getTimeColumnBuilder().writeLong(0L); |
| tsBlockBuilder.getColumnBuilder(0).writeLong(count); |
| tsBlockBuilder.declarePosition(); |
| return tsBlockBuilder.build(); |
| } |
| |
| @Override |
| public boolean isFinished() throws Exception { |
| return isFinished; |
| } |
| |
| @Override |
| public long calculateMaxPeekMemory() { |
| // the long used for count |
| return 8L; |
| } |
| |
| @Override |
| public long calculateMaxReturnSize() { |
| // the long used for count |
| return 8L; |
| } |
| |
| @Override |
| public long calculateRetainedSizeAfterCallingNext() { |
| return 0; |
| } |
| |
| @Override |
| public PlanNodeId getSourceId() { |
| return sourceId; |
| } |
| |
| @Override |
| public void close() throws Exception { |
| if (schemaReader != null) { |
| schemaReader.close(); |
| schemaReader = null; |
| } |
| } |
| } |