content: /*
   * 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.arrow.gandiva.expression;
  
  import com.google.protobuf.ByteString;
  import java.nio.charset.Charset;
  import org.apache.arrow.gandiva.exceptions.GandivaException;
  import org.apache.arrow.gandiva.ipc.GandivaTypes;
  
  /** Used to represent expression tree nodes representing utf8 constants. */
  class StringNode implements TreeNode {
    private static final Charset charset = Charset.forName("UTF-8");
    private final String value;
  
    public StringNode(String value) {
      this.value = value;
    }
  
    @Override
    public GandivaTypes.TreeNode toProtobuf() throws GandivaException {
      GandivaTypes.StringNode stringNode =
          GandivaTypes.StringNode.newBuilder()
              .setValue(ByteString.copyFrom(value.getBytes(charset)))
              .build();
  
      return GandivaTypes.TreeNode.newBuilder().setStringNode(stringNode).build();
    }
  }
  