content: /*
   * Copyright 1999-2018 Alibaba Group Holding Ltd.
   *
   * Licensed 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 com.alibaba.csp.sentinel.datasource;
  
  import com.alibaba.csp.sentinel.property.DynamicSentinelProperty;
  import com.alibaba.csp.sentinel.property.SentinelProperty;
  
  /**
   * The abstract readable data source provides basic functionality for loading and parsing config.
   *
   * @param <S> source data type
   * @param <T> target data type
   * @author Carpenter Lee
   * @author Eric Zhao
   */
  public abstract class AbstractDataSource<S, T> implements ReadableDataSource<S, T> {
  
      protected final Converter<S, T> parser;
      protected final SentinelProperty<T> property;
  
      public AbstractDataSource(Converter<S, T> parser) {
          if (parser == null) {
              throw new IllegalArgumentException("parser can't be null");
          }
          this.parser = parser;
          this.property = new DynamicSentinelProperty<T>();
      }
  
      @Override
      public T loadConfig() throws Exception {
          return loadConfig(readSource());
      }
  
      public T loadConfig(S conf) throws Exception {
          T value = parser.convert(conf);
          return value;
      }
  
      @Override
      public SentinelProperty<T> getProperty() {
          return property;
      }
  }
  