| /* |
| * 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.vxquery.runtime.functions.step; |
| |
| import java.io.IOException; |
| |
| import org.apache.vxquery.datamodel.accessors.TaggedValuePointable; |
| import org.apache.vxquery.datamodel.values.ValueTag; |
| import org.apache.vxquery.exceptions.ErrorCode; |
| import org.apache.vxquery.exceptions.SystemException; |
| |
| import edu.uci.ics.hyracks.algebricks.runtime.base.IScalarEvaluator; |
| import edu.uci.ics.hyracks.api.context.IHyracksTaskContext; |
| import edu.uci.ics.hyracks.data.std.api.IPointable; |
| import edu.uci.ics.hyracks.data.std.util.ArrayBackedValueStorage; |
| |
| public class DescendantPathStepScalarEvaluator extends AbstractDescendantPathStepScalarEvaluator { |
| private final TaggedValuePointable rootTVP; |
| |
| private final ArrayBackedValueStorage seqAbvs; |
| |
| public DescendantPathStepScalarEvaluator(IScalarEvaluator[] args, IHyracksTaskContext ctx) { |
| super(args, ctx); |
| rootTVP = (TaggedValuePointable) TaggedValuePointable.FACTORY.createPointable(); |
| seqAbvs = new ArrayBackedValueStorage(); |
| } |
| |
| @Override |
| protected final void evaluate(TaggedValuePointable[] args, IPointable result) throws SystemException { |
| try { |
| if (args[0].getTag() != ValueTag.NODE_TREE_TAG) { |
| throw new SystemException(ErrorCode.SYSE0001); |
| } |
| args[0].getValue(ntp); |
| |
| // Set up the result sequence and get the root node. |
| seqAbvs.reset(); |
| seqb.reset(seqAbvs); |
| ntp.getRootNode(rootTVP); |
| |
| // Solve for descendants. |
| searchSubtree(rootTVP); |
| |
| seqb.finish(); |
| result.set(seqAbvs); |
| } catch (IOException e) { |
| throw new SystemException(ErrorCode.SYSE0001, e); |
| } |
| } |
| |
| } |