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.kafka.common.serialization;
  
  import org.apache.kafka.common.errors.SerializationException;
  import org.apache.kafka.common.header.Headers;
  import org.apache.kafka.common.utils.Utils;
  
  import java.nio.ByteBuffer;
  import java.nio.charset.Charset;
  import java.nio.charset.IllegalCharsetNameException;
  import java.nio.charset.StandardCharsets;
  import java.nio.charset.UnsupportedCharsetException;
  import java.util.Map;
  
  /**
   * String encoding defaults to UTF8 and can be customized by setting the property key.deserializer.encoding,
   * value.deserializer.encoding or deserializer.encoding. The first two take precedence over the last.
   */
  public class StringDeserializer implements Deserializer<String> {
      private Charset encoding = StandardCharsets.UTF_8;
  
      @Override
      public void configure(Map<String, ?> configs, boolean isKey) {
          String propertyName = isKey ? "key.deserializer.encoding" : "value.deserializer.encoding";
          Object encodingValue = configs.get(propertyName);
          if (encodingValue == null)
              encodingValue = configs.get("deserializer.encoding");
          if (encodingValue instanceof String) {
              String encodingName = (String) encodingValue;
              try {
                  encoding = Charset.forName(encodingName);
              } catch (UnsupportedCharsetException | IllegalCharsetNameException e) {
                  throw new SerializationException("Unsupported encoding " + encodingName, e);
              }
          }
      }
  
      @Override
      public String deserialize(String topic, byte[] data) {
          if (data == null)
              return null;
          else
              return new String(data, encoding);
      }
  
      @Override
      public String deserialize(String topic, Headers headers, ByteBuffer data) {
          if (data == null) {
              return null;
          }
  
          if (data.hasArray()) {
              return new String(data.array(), data.position() + data.arrayOffset(), data.remaining(), encoding);
          }
          return new String(Utils.toArray(data), encoding);
      }
  }
  