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.spi;
  
  import java.lang.annotation.*;
  
  /**
   * Annotation for Provider class of SPI.
   *
   * @see SpiLoader
   * @author cdfive
   */
  @Retention(RetentionPolicy.RUNTIME)
  @Target({ElementType.TYPE})
  @Documented
  public @interface Spi {
  
      /**
       * Alias name of Provider class
       */
      String value() default "";
  
      /**
       * Whether create singleton instance
       */
      boolean isSingleton() default true;
  
      /**
       * Whether is the default Provider
       */
      boolean isDefault() default false;
  
      /**
       * Order priority of Provider class
       */
      int order() default 0;
  
      int ORDER_HIGHEST = Integer.MIN_VALUE;
  
      int ORDER_LOWEST = Integer.MAX_VALUE;
  }
  