/**
* 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.hadoop.hive.ql.exec.vector;
import org.apache.hadoop.hive.ql.CompilationOpContext;
import org.apache.hadoop.hive.ql.exec.LimitOperator;
import org.apache.hadoop.hive.ql.metadata.HiveException;
import org.apache.hadoop.hive.ql.plan.LimitDesc;
import org.apache.hadoop.hive.ql.plan.OperatorDesc;
import com.google.common.annotations.VisibleForTesting;
/**
* Limit operator implementation Limits the number of rows to be passed on.
**/
public class VectorLimitOperator extends LimitOperator {
private static final long serialVersionUID = 1L;
/** Kryo ctor. */
@VisibleForTesting
public VectorLimitOperator() {
super();
}
public VectorLimitOperator(CompilationOpContext ctx) {
super(ctx);
}
public VectorLimitOperator(
CompilationOpContext ctx, VectorizationContext vContext, OperatorDesc conf) {
this(ctx);
this.conf = (LimitDesc) conf;
}
@Override
public void process(Object row, int tag) throws HiveException {
VectorizedRowBatch batch = (VectorizedRowBatch) row;
if (currCount + batch.size < offset) {
currCount += batch.size;
} else if (currCount >= offset + limit) {
setDone(true);
} else {
int skipSize = 0;
if (currCount < offset) {
skipSize = offset - currCount;
}
//skip skipSize rows of batch
batch.size = Math.min(batch.size, offset + limit - currCount);
if (batch.selectedInUse == false) {
batch.selectedInUse = true;
batch.selected = new int[batch.size];
for (int i = 0; i < batch.size - skipSize; i++) {
batch.selected[i] = skipSize + i;
}
} else {
for (int i = 0; i < batch.size - skipSize; i++) {
batch.selected[i] = batch.selected[skipSize + i];
}
}
forward(row, inputObjInspectors[tag]);
currCount += batch.size;
}
}
}