/**
   * Sets up projection that will transfer all of the columns in batch, and also populate the
   * partition column based on which partition a record falls into in the partition table
   *
   * @param batch
   * @throws SchemaChangeException
   */
  protected void setupNewSchema(VectorAccessible batch) throws SchemaChangeException {
    container.clear();
    final ErrorCollector collector = new ErrorCollectorImpl();
    final List<TransferPair> transfers = Lists.newArrayList();

    final ClassGenerator<OrderedPartitionProjector> cg =
        CodeGenerator.getRoot(
            OrderedPartitionProjector.TEMPLATE_DEFINITION, context.getFunctionRegistry());

    for (VectorWrapper<?> vw : batch) {
      TransferPair tp = vw.getValueVector().getTransferPair();
      transfers.add(tp);
      container.add(tp.getTo());
    }

    cg.setMappingSet(mainMapping);

    int count = 0;
    for (Ordering od : popConfig.getOrderings()) {
      final LogicalExpression expr =
          ExpressionTreeMaterializer.materialize(
              od.getExpr(), batch, collector, context.getFunctionRegistry());
      if (collector.hasErrors())
        throw new SchemaChangeException(
            "Failure while materializing expression. " + collector.toErrorString());
      cg.setMappingSet(incomingMapping);
      ClassGenerator.HoldingContainer left = cg.addExpr(expr, false);
      cg.setMappingSet(partitionMapping);
      ClassGenerator.HoldingContainer right =
          cg.addExpr(
              new ValueVectorReadExpression(new TypedFieldId(expr.getMajorType(), count++)), false);
      cg.setMappingSet(mainMapping);

      LogicalExpression fh =
          FunctionGenerationHelper.getComparator(left, right, context.getFunctionRegistry());
      ClassGenerator.HoldingContainer out = cg.addExpr(fh, false);
      JConditional jc = cg.getEvalBlock()._if(out.getValue().ne(JExpr.lit(0)));

      if (od.getDirection() == Direction.ASCENDING) {
        jc._then()._return(out.getValue());
      } else {
        jc._then()._return(out.getValue().minus());
      }
    }

    cg.getEvalBlock()._return(JExpr.lit(0));

    container.add(this.partitionKeyVector);
    container.buildSchema(batch.getSchema().getSelectionVectorMode());

    try {
      this.projector = context.getImplementationClass(cg);
      projector.setup(
          context, batch, this, transfers, partitionVectors, partitions, popConfig.getRef());
    } catch (ClassTransformationException | IOException e) {
      throw new SchemaChangeException("Failure while attempting to load generated class", e);
    }
  }
  private MSorter createNewMSorter(
      FragmentContext context,
      List<Ordering> orderings,
      VectorAccessible batch,
      MappingSet mainMapping,
      MappingSet leftMapping,
      MappingSet rightMapping)
      throws ClassTransformationException, IOException, SchemaChangeException {
    CodeGenerator<MSorter> cg =
        CodeGenerator.get(
            MSorter.TEMPLATE_DEFINITION, context.getFunctionRegistry(), context.getOptions());
    ClassGenerator<MSorter> g = cg.getRoot();
    g.setMappingSet(mainMapping);

    for (Ordering od : orderings) {
      // first, we rewrite the evaluation stack for each side of the comparison.
      ErrorCollector collector = new ErrorCollectorImpl();
      final LogicalExpression expr =
          ExpressionTreeMaterializer.materialize(
              od.getExpr(), batch, collector, context.getFunctionRegistry());
      if (collector.hasErrors()) {
        throw new SchemaChangeException(
            "Failure while materializing expression. " + collector.toErrorString());
      }
      g.setMappingSet(leftMapping);
      HoldingContainer left = g.addExpr(expr, ClassGenerator.BlkCreateMode.FALSE);
      g.setMappingSet(rightMapping);
      HoldingContainer right = g.addExpr(expr, ClassGenerator.BlkCreateMode.FALSE);
      g.setMappingSet(mainMapping);

      // next we wrap the two comparison sides and add the expression block for the comparison.
      LogicalExpression fh =
          FunctionGenerationHelper.getOrderingComparator(
              od.nullsSortHigh(), left, right, context.getFunctionRegistry());
      HoldingContainer out = g.addExpr(fh, ClassGenerator.BlkCreateMode.FALSE);
      JConditional jc = g.getEvalBlock()._if(out.getValue().ne(JExpr.lit(0)));

      if (od.getDirection() == Direction.ASCENDING) {
        jc._then()._return(out.getValue());
      } else {
        jc._then()._return(out.getValue().minus());
      }
      g.rotateBlock();
    }

    g.rotateBlock();
    g.getEvalBlock()._return(JExpr.lit(0));

    return context.getImplementationClass(cg);
  }
  /**
   * Creates a copier that does a project for every Nth record from a VectorContainer incoming into
   * VectorContainer outgoing. Each Ordering in orderings generates a column, and evaluation of the
   * expression associated with each Ordering determines the value of each column. These records
   * will later be sorted based on the values in each column, in the same order as the orderings.
   *
   * @param sv4
   * @param incoming
   * @param outgoing
   * @param orderings
   * @return
   * @throws SchemaChangeException
   */
  private SampleCopier getCopier(
      SelectionVector4 sv4,
      VectorContainer incoming,
      VectorContainer outgoing,
      List<Ordering> orderings,
      List<ValueVector> localAllocationVectors)
      throws SchemaChangeException {
    final ErrorCollector collector = new ErrorCollectorImpl();
    final ClassGenerator<SampleCopier> cg =
        CodeGenerator.getRoot(SampleCopier.TEMPLATE_DEFINITION, context.getFunctionRegistry());

    int i = 0;
    for (Ordering od : orderings) {
      final LogicalExpression expr =
          ExpressionTreeMaterializer.materialize(
              od.getExpr(), incoming, collector, context.getFunctionRegistry());
      SchemaPath schemaPath = SchemaPath.getSimplePath("f" + i++);
      TypeProtos.MajorType.Builder builder =
          TypeProtos.MajorType.newBuilder()
              .mergeFrom(expr.getMajorType())
              .clearMode()
              .setMode(TypeProtos.DataMode.REQUIRED);
      TypeProtos.MajorType newType = builder.build();
      MaterializedField outputField = MaterializedField.create(schemaPath, newType);
      if (collector.hasErrors()) {
        throw new SchemaChangeException(
            String.format(
                "Failure while trying to materialize incoming schema.  Errors:\n %s.",
                collector.toErrorString()));
      }

      ValueVector vector = TypeHelper.getNewVector(outputField, oContext.getAllocator());
      localAllocationVectors.add(vector);
      TypedFieldId fid = outgoing.add(vector);
      ValueVectorWriteExpression write = new ValueVectorWriteExpression(fid, expr, true);
      HoldingContainer hc = cg.addExpr(write);
      cg.getEvalBlock()._if(hc.getValue().eq(JExpr.lit(0)))._then()._return(JExpr.FALSE);
    }
    cg.rotateBlock();
    cg.getEvalBlock()._return(JExpr.TRUE);
    outgoing.buildSchema(BatchSchema.SelectionVectorMode.NONE);
    try {
      SampleCopier sampleCopier = context.getImplementationClass(cg);
      sampleCopier.setupCopier(context, sv4, incoming, outgoing);
      return sampleCopier;
    } catch (ClassTransformationException | IOException e) {
      throw new SchemaChangeException(e);
    }
  }
  private void generateComparisons(ClassGenerator<?> g, VectorAccessible batch)
      throws SchemaChangeException {
    g.setMappingSet(MAIN_MAPPING);

    for (Ordering od : popConfig.getOrderings()) {
      // first, we rewrite the evaluation stack for each side of the comparison.
      ErrorCollector collector = new ErrorCollectorImpl();
      final LogicalExpression expr =
          ExpressionTreeMaterializer.materialize(
              od.getExpr(), batch, collector, context.getFunctionRegistry());
      if (collector.hasErrors()) {
        throw new SchemaChangeException(
            "Failure while materializing expression. " + collector.toErrorString());
      }
      g.setMappingSet(LEFT_MAPPING);
      HoldingContainer left = g.addExpr(expr, ClassGenerator.BlkCreateMode.FALSE);
      g.setMappingSet(RIGHT_MAPPING);
      HoldingContainer right = g.addExpr(expr, ClassGenerator.BlkCreateMode.FALSE);
      g.setMappingSet(MAIN_MAPPING);

      // next we wrap the two comparison sides and add the expression block for the comparison.
      LogicalExpression fh =
          FunctionGenerationHelper.getOrderingComparator(
              od.nullsSortHigh(), left, right, context.getFunctionRegistry());
      HoldingContainer out = g.addExpr(fh, ClassGenerator.BlkCreateMode.FALSE);
      JConditional jc = g.getEvalBlock()._if(out.getValue().ne(JExpr.lit(0)));

      if (od.getDirection() == Direction.ASCENDING) {
        jc._then()._return(out.getValue());
      } else {
        jc._then()._return(out.getValue().minus());
      }
      g.rotateBlock();
    }

    g.rotateBlock();
    g.getEvalBlock()._return(JExpr.lit(0));
  }
  private StreamingAggregator createAggregatorInternal()
      throws SchemaChangeException, ClassTransformationException, IOException {
    ClassGenerator<StreamingAggregator> cg =
        CodeGenerator.getRoot(
            StreamingAggTemplate.TEMPLATE_DEFINITION, context.getFunctionRegistry());
    container.clear();

    LogicalExpression[] keyExprs = new LogicalExpression[popConfig.getKeys().length];
    LogicalExpression[] valueExprs = new LogicalExpression[popConfig.getExprs().length];
    TypedFieldId[] keyOutputIds = new TypedFieldId[popConfig.getKeys().length];

    ErrorCollector collector = new ErrorCollectorImpl();

    for (int i = 0; i < keyExprs.length; i++) {
      final NamedExpression ne = popConfig.getKeys()[i];
      final LogicalExpression expr =
          ExpressionTreeMaterializer.materialize(
              ne.getExpr(), incoming, collector, context.getFunctionRegistry());
      if (expr == null) {
        continue;
      }
      keyExprs[i] = expr;
      final MaterializedField outputField =
          MaterializedField.create(ne.getRef(), expr.getMajorType());
      final ValueVector vector = TypeHelper.getNewVector(outputField, oContext.getAllocator());
      keyOutputIds[i] = container.add(vector);
    }

    for (int i = 0; i < valueExprs.length; i++) {
      final NamedExpression ne = popConfig.getExprs()[i];
      final LogicalExpression expr =
          ExpressionTreeMaterializer.materialize(
              ne.getExpr(), incoming, collector, context.getFunctionRegistry());
      if (expr instanceof IfExpression) {
        throw UserException.unsupportedError(
                new UnsupportedOperationException(
                    "Union type not supported in aggregate functions"))
            .build(logger);
      }
      if (expr == null) {
        continue;
      }

      final MaterializedField outputField =
          MaterializedField.create(ne.getRef(), expr.getMajorType());
      ValueVector vector = TypeHelper.getNewVector(outputField, oContext.getAllocator());
      TypedFieldId id = container.add(vector);
      valueExprs[i] = new ValueVectorWriteExpression(id, expr, true);
    }

    if (collector.hasErrors()) {
      throw new SchemaChangeException(
          "Failure while materializing expression. " + collector.toErrorString());
    }

    setupIsSame(cg, keyExprs);
    setupIsSameApart(cg, keyExprs);
    addRecordValues(cg, valueExprs);
    outputRecordKeys(cg, keyOutputIds, keyExprs);
    outputRecordKeysPrev(cg, keyOutputIds, keyExprs);

    cg.getBlock("resetValues")._return(JExpr.TRUE);
    getIndex(cg);

    container.buildSchema(SelectionVectorMode.NONE);
    StreamingAggregator agg = context.getImplementationClass(cg);
    agg.setup(oContext, incoming, this);
    return agg;
  }
  private IterOutcome doWork()
      throws ClassTransformationException, IOException, SchemaChangeException {
    if (allocationVectors != null) {
      for (ValueVector v : allocationVectors) {
        v.clear();
      }
    }

    allocationVectors = Lists.newArrayList();
    transfers.clear();

    final ClassGenerator<UnionAller> cg =
        CodeGenerator.getRoot(UnionAller.TEMPLATE_DEFINITION, context.getFunctionRegistry());
    int index = 0;
    for (VectorWrapper<?> vw : current) {
      ValueVector vvIn = vw.getValueVector();
      // get the original input column names
      SchemaPath inputPath = vvIn.getField().getPath();
      // get the renamed column names
      SchemaPath outputPath = outputFields.get(index).getPath();

      final ErrorCollector collector = new ErrorCollectorImpl();
      // According to input data names, Minortypes, Datamodes, choose to
      // transfer directly,
      // rename columns or
      // cast data types (Minortype or DataMode)
      if (hasSameTypeAndMode(outputFields.get(index), vw.getValueVector().getField())) {
        // Transfer column
        if (outputFields.get(index).getPath().equals(inputPath)) {
          final LogicalExpression expr =
              ExpressionTreeMaterializer.materialize(
                  inputPath, current, collector, context.getFunctionRegistry());
          if (collector.hasErrors()) {
            throw new SchemaChangeException(
                String.format(
                    "Failure while trying to materialize incoming schema.  Errors:\n %s.",
                    collector.toErrorString()));
          }

          ValueVectorReadExpression vectorRead = (ValueVectorReadExpression) expr;
          ValueVector vvOut =
              container.addOrGet(MaterializedField.create(outputPath, vectorRead.getMajorType()));
          TransferPair tp = vvIn.makeTransferPair(vvOut);
          transfers.add(tp);
          // Copy data in order to rename the column
        } else {
          final LogicalExpression expr =
              ExpressionTreeMaterializer.materialize(
                  inputPath, current, collector, context.getFunctionRegistry());
          if (collector.hasErrors()) {
            throw new SchemaChangeException(
                String.format(
                    "Failure while trying to materialize incoming schema.  Errors:\n %s.",
                    collector.toErrorString()));
          }

          MaterializedField outputField = MaterializedField.create(outputPath, expr.getMajorType());
          ValueVector vv = container.addOrGet(outputField, callBack);
          allocationVectors.add(vv);
          TypedFieldId fid = container.getValueVectorId(outputField.getPath());
          ValueVectorWriteExpression write = new ValueVectorWriteExpression(fid, expr, true);
          cg.addExpr(write);
        }
        // Cast is necessary
      } else {
        LogicalExpression expr =
            ExpressionTreeMaterializer.materialize(
                inputPath, current, collector, context.getFunctionRegistry());
        if (collector.hasErrors()) {
          throw new SchemaChangeException(
              String.format(
                  "Failure while trying to materialize incoming schema.  Errors:\n %s.",
                  collector.toErrorString()));
        }

        // If the inputs' DataMode is required and the outputs' DataMode is not required
        // cast to the one with the least restriction
        if (vvIn.getField().getType().getMode() == DataMode.REQUIRED
            && outputFields.get(index).getType().getMode() != DataMode.REQUIRED) {
          expr =
              ExpressionTreeMaterializer.convertToNullableType(
                  expr,
                  vvIn.getField().getType().getMinorType(),
                  context.getFunctionRegistry(),
                  collector);
          if (collector.hasErrors()) {
            throw new SchemaChangeException(
                String.format(
                    "Failure while trying to materialize incoming schema.  Errors:\n %s.",
                    collector.toErrorString()));
          }
        }

        // If two inputs' MinorTypes are different,
        // Insert a cast before the Union operation
        if (vvIn.getField().getType().getMinorType()
            != outputFields.get(index).getType().getMinorType()) {
          expr =
              ExpressionTreeMaterializer.addCastExpression(
                  expr,
                  outputFields.get(index).getType(),
                  context.getFunctionRegistry(),
                  collector);
          if (collector.hasErrors()) {
            throw new SchemaChangeException(
                String.format(
                    "Failure while trying to materialize incoming schema.  Errors:\n %s.",
                    collector.toErrorString()));
          }
        }

        final MaterializedField outputField =
            MaterializedField.create(outputPath, expr.getMajorType());
        ValueVector vector = container.addOrGet(outputField, callBack);
        allocationVectors.add(vector);
        TypedFieldId fid = container.getValueVectorId(outputField.getPath());

        boolean useSetSafe = !(vector instanceof FixedWidthVector);
        ValueVectorWriteExpression write = new ValueVectorWriteExpression(fid, expr, useSetSafe);
        cg.addExpr(write);
      }
      ++index;
    }

    unionall = context.getImplementationClass(cg.getCodeGenerator());
    unionall.setup(context, current, this, transfers);

    if (!schemaAvailable) {
      container.buildSchema(BatchSchema.SelectionVectorMode.NONE);
      schemaAvailable = true;
    }

    if (!doAlloc()) {
      return IterOutcome.OUT_OF_MEMORY;
    }

    recordCount = unionall.unionRecords(0, current.getRecordCount(), 0);
    setValueCount(recordCount);
    return IterOutcome.OK;
  }