vxquery-core/src/main/java/org/apache/vxquery/runtime/functions/jsonitem/ObjectConstructorScalarEvaluator.java

/*
 * 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.jsonitem;

import org.apache.hyracks.algebricks.runtime.base.IScalarEvaluator;
import org.apache.hyracks.api.context.IHyracksTaskContext;
import org.apache.hyracks.data.std.api.IPointable;
import org.apache.hyracks.data.std.primitive.UTF8StringPointable;
import org.apache.hyracks.data.std.primitive.VoidPointable;
import org.apache.hyracks.data.std.util.ArrayBackedValueStorage;
import org.apache.vxquery.datamodel.accessors.SequencePointable;
import org.apache.vxquery.datamodel.accessors.TaggedValuePointable;
import org.apache.vxquery.datamodel.builders.jsonitem.ObjectBuilder;
import org.apache.vxquery.datamodel.values.ValueTag;
import org.apache.vxquery.exceptions.ErrorCode;
import org.apache.vxquery.exceptions.SystemException;
import org.apache.vxquery.runtime.functions.base.AbstractTaggedValueArgumentScalarEvaluator;
import org.apache.vxquery.runtime.functions.util.FunctionHelper;

import java.io.IOException;

public class ObjectConstructorScalarEvaluator extends AbstractTaggedValueArgumentScalarEvaluator {
    private ObjectBuilder ob;
    private TaggedValuePointable[] pointables;
    private IPointable vp;
    private UTF8StringPointable sp;
    private SequencePointable seqp;
    protected final IHyracksTaskContext ctx;
    private final ArrayBackedValueStorage abvs;

    public ObjectConstructorScalarEvaluator(IHyracksTaskContext ctx, IScalarEvaluator[] args) {
        super(args);
        this.ctx = ctx;
        abvs = new ArrayBackedValueStorage();
        ob = new ObjectBuilder();
        vp = VoidPointable.FACTORY.createPointable();
        sp = (UTF8StringPointable) UTF8StringPointable.FACTORY.createPointable();
        seqp = (SequencePointable) SequencePointable.FACTORY.createPointable();
    }

    private boolean isDuplicate(TaggedValuePointable tempKey) {
        for (TaggedValuePointable tvp : pointables) {
            tempKey.getValue(vp);
            if (tvp != null && FunctionHelper.arraysEqual(tvp, vp)) {
                return true;
            }
        }
        return false;
    }

    @Override
    protected void evaluate(TaggedValuePointable[] args, IPointable result) throws SystemException {
        TaggedValuePointable tvp;
        TaggedValuePointable tempKey = ppool.takeOne(TaggedValuePointable.class);
        TaggedValuePointable tempValue = ppool.takeOne(TaggedValuePointable.class);
        try {
            ob.reset(abvs);

            tvp = args[0];
            if (tvp.getTag() == ValueTag.SEQUENCE_TAG) {
                tvp.getValue(seqp);
                int len = seqp.getEntryCount();
                pointables = new TaggedValuePointable[len / 2];
                for (int i = 0; i < len; i += 2) {
                    seqp.getEntry(i, tempKey);
                    seqp.getEntry(i + 1, tempValue);
                    if (!isDuplicate(tempKey)) {
                        pointables[i / 2] = (TaggedValuePointable) TaggedValuePointable.FACTORY.createPointable();
                        tempKey.getValue(pointables[i / 2]);
                        sp.set(vp);
                        ob.addItem(sp, tempValue);
                    } else {
                        throw new SystemException(ErrorCode.JNDY0003);
                    }
                }
            }
            ob.finish();
            result.set(abvs);
        } catch (IOException e) {
            throw new SystemException(ErrorCode.SYSE0001, e);
        } finally {
            ppool.giveBack(tempKey);
            ppool.giveBack(tempValue);
        }
    }
}