iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/statement/literal/NullLiteral.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.plan.statement.literal;

import org.apache.iotdb.tsfile.common.conf.TSFileConfig;
import org.apache.iotdb.tsfile.file.metadata.enums.TSDataType;
import org.apache.iotdb.tsfile.utils.Binary;
import org.apache.iotdb.tsfile.utils.ReadWriteIOUtils;

import java.io.DataOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;

public class NullLiteral extends Literal {

  @Override
  public void serialize(ByteBuffer byteBuffer) {
    ReadWriteIOUtils.write(LiteralType.NULL.ordinal(), byteBuffer);
  }

  @Override
  public void serialize(DataOutputStream stream) throws IOException {
    ReadWriteIOUtils.write(LiteralType.NULL.ordinal(), stream);
  }

  @Override
  public boolean isDataTypeConsistency(TSDataType dataType) {
    return false;
  }

  @Override
  public String getDataTypeString() {
    return "NULL";
  }

  @Override
  public Binary getBinary() {
    return new Binary("null", TSFileConfig.STRING_CHARSET);
  }

  @Override
  public boolean equals(Object o) {
    if (this == o) {
      return true;
    }
    return o != null && getClass() == o.getClass();
  }

  @Override
  public int hashCode() {
    return getClass().hashCode();
  }

  @Override
  public String toString() {
    return "null";
  }
}