testkit/src/main/java/org/apache/calcite/test/catalog/CountingFactory.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.calcite.test.catalog;

import org.apache.calcite.plan.RelOptTable;
import org.apache.calcite.rel.type.RelDataType;
import org.apache.calcite.rel.type.RelDataTypeField;
import org.apache.calcite.rex.RexBuilder;
import org.apache.calcite.rex.RexNode;
import org.apache.calcite.schema.ColumnStrategy;
import org.apache.calcite.sql.SqlFunction;
import org.apache.calcite.sql2rel.InitializerContext;
import org.apache.calcite.sql2rel.InitializerExpressionFactory;
import org.apache.calcite.sql2rel.NullInitializerExpressionFactory;

import com.google.common.collect.ImmutableList;

import java.math.BigDecimal;
import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

/** To check whether
 * {@link InitializerExpressionFactory#newColumnDefaultValue} is called.
 *
 * <p>If a column is in {@code defaultColumns}, returns 1 as the default
 * value. */
public class CountingFactory extends NullInitializerExpressionFactory {
  public static final ThreadLocal<AtomicInteger> THREAD_CALL_COUNT =
      ThreadLocal.withInitial(AtomicInteger::new);

  private final List<String> defaultColumns;

  CountingFactory(List<String> defaultColumns) {
    this.defaultColumns = ImmutableList.copyOf(defaultColumns);
  }

  @Override public ColumnStrategy generationStrategy(RelOptTable table,
      int iColumn) {
    final RelDataTypeField field =
        table.getRowType().getFieldList().get(iColumn);
    if (defaultColumns.contains(field.getName())) {
      return ColumnStrategy.DEFAULT;
    }
    return super.generationStrategy(table, iColumn);
  }

  @Override public RexNode newColumnDefaultValue(RelOptTable table,
      int iColumn, InitializerContext context) {
    THREAD_CALL_COUNT.get().incrementAndGet();
    final RelDataTypeField field =
        table.getRowType().getFieldList().get(iColumn);
    if (defaultColumns.contains(field.getName())) {
      final RexBuilder rexBuilder = context.getRexBuilder();
      return rexBuilder.makeExactLiteral(BigDecimal.ONE);
    }
    return super.newColumnDefaultValue(table, iColumn, context);
  }

  @Override public RexNode newAttributeInitializer(RelDataType type,
      SqlFunction constructor, int iAttribute,
      List<RexNode> constructorArgs, InitializerContext context) {
    THREAD_CALL_COUNT.get().incrementAndGet();
    return super.newAttributeInitializer(type, constructor, iAttribute,
       constructorArgs, context);
  }
}