| /** |
| * 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.drill.exec.record; |
| |
| import org.apache.drill.exec.exception.SchemaChangeException; |
| import org.apache.drill.exec.memory.OutOfMemoryException; |
| import org.apache.drill.exec.ops.FragmentContext; |
| import org.apache.drill.exec.physical.base.PhysicalOperator; |
| import org.apache.drill.exec.record.BatchSchema.SelectionVectorMode; |
| import org.apache.drill.exec.vector.SchemaChangeCallBack; |
| |
| public abstract class AbstractSingleRecordBatch<T extends PhysicalOperator> extends AbstractRecordBatch<T> { |
| final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(this.getClass()); |
| |
| protected final RecordBatch incoming; |
| protected boolean outOfMemory = false; |
| protected SchemaChangeCallBack callBack = new SchemaChangeCallBack(); |
| |
| public AbstractSingleRecordBatch(T popConfig, FragmentContext context, RecordBatch incoming) throws OutOfMemoryException { |
| super(popConfig, context, false); |
| this.incoming = incoming; |
| } |
| |
| @Override |
| protected void killIncoming(boolean sendUpstream) { |
| incoming.kill(sendUpstream); |
| } |
| |
| @Override |
| public IterOutcome innerNext() { |
| // Short circuit if record batch has already sent all data and is done |
| if (state == BatchState.DONE) { |
| return IterOutcome.NONE; |
| } |
| |
| IterOutcome upstream = next(incoming); |
| if (state != BatchState.FIRST && upstream == IterOutcome.OK && incoming.getRecordCount() == 0) { |
| do { |
| for (VectorWrapper w : incoming) { |
| w.clear(); |
| } |
| } while ((upstream = next(incoming)) == IterOutcome.OK && incoming.getRecordCount() == 0); |
| } |
| if ((state == BatchState.FIRST) && upstream == IterOutcome.OK) { |
| upstream = IterOutcome.OK_NEW_SCHEMA; |
| } |
| switch (upstream) { |
| case NONE: |
| case NOT_YET: |
| case STOP: |
| if (state == BatchState.FIRST) { |
| container.buildSchema(SelectionVectorMode.NONE); |
| } |
| return upstream; |
| case OUT_OF_MEMORY: |
| return upstream; |
| case OK_NEW_SCHEMA: |
| if (state == BatchState.FIRST) { |
| state = BatchState.NOT_FIRST; |
| } |
| try { |
| stats.startSetup(); |
| if (!setupNewSchema()) { |
| upstream = IterOutcome.OK; |
| } |
| } catch (SchemaChangeException ex) { |
| kill(false); |
| logger.error("Failure during query", ex); |
| context.fail(ex); |
| return IterOutcome.STOP; |
| } finally { |
| stats.stopSetup(); |
| } |
| // fall through. |
| case OK: |
| assert state != BatchState.FIRST : "First batch should be OK_NEW_SCHEMA"; |
| container.zeroVectors(); |
| IterOutcome out = doWork(); |
| |
| // since doWork method does not know if there is a new schema, it will always return IterOutcome.OK if it was successful. |
| // But if upstream is IterOutcome.OK_NEW_SCHEMA, we should return that |
| if (out != IterOutcome.OK) { |
| upstream = out; |
| } |
| |
| if (outOfMemory) { |
| outOfMemory = false; |
| return IterOutcome.OUT_OF_MEMORY; |
| } |
| |
| // Check if schema has changed |
| if (callBack.getSchemaChange()) { |
| return IterOutcome.OK_NEW_SCHEMA; |
| } |
| |
| return upstream; // change if upstream changed, otherwise normal. |
| default: |
| throw new UnsupportedOperationException(); |
| } |
| } |
| |
| @Override |
| public void cleanup() { |
| // logger.debug("Cleaning up."); |
| super.cleanup(); |
| incoming.cleanup(); |
| } |
| |
| @Override |
| public BatchSchema getSchema() { |
| return container.getSchema(); |
| } |
| |
| protected abstract boolean setupNewSchema() throws SchemaChangeException; |
| protected abstract IterOutcome doWork(); |
| } |