code: @Override
    protected Schema fetchSchemaByKey(String key) throws SchemaRegistryException {
      String schemaUrl = KafkaAvroSchemaRegistry.this.url + GET_RESOURCE_BY_ID + key;
  
      GetMethod get = new GetMethod(schemaUrl);
  
      int statusCode;
      String schemaString;
      HttpClient httpClient = this.borrowClient();
      try {
        statusCode = httpClient.executeMethod(get);
        schemaString = get.getResponseBodyAsString();
      } catch (IOException e) {
        throw new SchemaRegistryException(e);
      } finally {
        get.releaseConnection();
        this.httpClientPool.returnObject(httpClient);
      }
  
      if (statusCode != HttpStatus.SC_OK) {
        throw new SchemaRegistryException(
            String.format("Schema with key %s cannot be retrieved, statusCode = %d", key, statusCode));
      }
  
      Schema schema;
      try {
        schema = new Schema.Parser().parse(schemaString);
      } catch (Throwable t) {
        throw new SchemaRegistryException(String.format("Schema with ID = %s cannot be parsed", key), t);
      }
  
      return schema;
    }
docs: Fetch schema by key.