iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/transformation/dag/column/ternary/CompareTernaryColumnTransformer.java

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 * 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
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package org.apache.iotdb.db.queryengine.transformation.dag.column.ternary;

import org.apache.iotdb.db.queryengine.transformation.dag.column.ColumnTransformer;
import org.apache.iotdb.tsfile.read.common.block.column.Column;
import org.apache.iotdb.tsfile.read.common.block.column.ColumnBuilder;
import org.apache.iotdb.tsfile.read.common.type.Type;
import org.apache.iotdb.tsfile.read.common.type.TypeEnum;

public abstract class CompareTernaryColumnTransformer extends TernaryColumnTransformer {
  protected CompareTernaryColumnTransformer(
      Type returnType,
      ColumnTransformer firstColumnTransformer,
      ColumnTransformer secondColumnTransformer,
      ColumnTransformer thirdColumnTransformer) {
    super(returnType, firstColumnTransformer, secondColumnTransformer, thirdColumnTransformer);
  }

  @Override
  public void evaluate() {
    firstColumnTransformer.tryEvaluate();
    secondColumnTransformer.tryEvaluate();
    thirdColumnTransformer.tryEvaluate();
    // attention: get positionCount before calling getColumn
    int positionCount = firstColumnTransformer.getColumnCachePositionCount();
    Column firstColumn = firstColumnTransformer.getColumn();
    Column secondColumn = secondColumnTransformer.getColumn();
    Column thirdColumn = thirdColumnTransformer.getColumn();
    ColumnBuilder columnBuilder = returnType.createColumnBuilder(positionCount);
    doTransform(firstColumn, secondColumn, thirdColumn, columnBuilder, positionCount);
    initializeColumnCache(columnBuilder.build());
  }

  @Override
  protected final void checkType() {
    if (firstColumnTransformer.isReturnTypeNumeric()
            && secondColumnTransformer.isReturnTypeNumeric()
            && thirdColumnTransformer.isReturnTypeNumeric()
        || firstColumnTransformer.typeEquals(TypeEnum.BINARY)
            && secondColumnTransformer.typeEquals(TypeEnum.BINARY)
            && thirdColumnTransformer.typeEquals(TypeEnum.BINARY)) {
      return;
    }

    throw new UnsupportedOperationException(
        "The Type of three subExpression should be all Numeric or Text");
  }

  protected abstract void doTransform(
      Column firstColumn,
      Column secondColumn,
      Column thirdColumn,
      ColumnBuilder builder,
      int positionCount);
}