iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/transformation/dag/transformer/unary/scalar/ReplaceFunctionTransformer.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.iotdb.db.queryengine.transformation.dag.transformer.unary.scalar;

import org.apache.iotdb.db.exception.query.QueryProcessException;
import org.apache.iotdb.db.queryengine.transformation.api.LayerPointReader;
import org.apache.iotdb.db.queryengine.transformation.dag.transformer.unary.UnaryTransformer;
import org.apache.iotdb.tsfile.common.conf.TSFileConfig;
import org.apache.iotdb.tsfile.file.metadata.enums.TSDataType;
import org.apache.iotdb.tsfile.utils.BytesUtils;

import java.io.IOException;

public class ReplaceFunctionTransformer extends UnaryTransformer {
  private final String from;
  private final String to;

  public ReplaceFunctionTransformer(LayerPointReader layerPointReader, String from, String to) {
    super(layerPointReader);
    this.from = from;
    this.to = to;
  }

  @Override
  public TSDataType getDataType() {
    return TSDataType.TEXT;
  }

  @Override
  protected void transformAndCache() throws QueryProcessException, IOException {
    cachedBinary =
        BytesUtils.valueOf(
            layerPointReader
                .currentBinary()
                .getStringValue(TSFileConfig.STRING_CHARSET)
                .replace(from, to));
  }
}