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.distributedlog.injector;
  
  /**
   * Failure Injector that works in asynchronous way.
   */
  public interface AsyncFailureInjector {
  
      AsyncFailureInjector NULL = new AsyncFailureInjector() {
          @Override
          public void injectErrors(boolean enabled) {
              // no-op
          }
  
          @Override
          public boolean shouldInjectErrors() {
              return false;
          }
  
          @Override
          public void injectDelays(boolean enabled) {
              // no-op
          }
  
          @Override
          public boolean shouldInjectDelays() {
              return false;
          }
  
          @Override
          public int getInjectedDelayMs() {
              return 0;
          }
  
          @Override
          public void injectStops(boolean enabled) {
              // no-op
          }
  
          @Override
          public boolean shouldInjectStops() {
              return false;
          }
  
          @Override
          public boolean shouldInjectCorruption(long startEntryId, long endEntryId) {
              return false;
          }
  
          @Override
          public String toString() {
              return "NULL";
          }
      };
  
      /**
       * Enable or disable error injection.
       *
       * @param enabled
       *          flag to enable or disable error injection.
       */
      void injectErrors(boolean enabled);
  
      /**
       * Return the flag indicating if should inject errors.
       *
       * @return true to inject errors otherwise false.
       */
      boolean shouldInjectErrors();
  
      /**
       * Enable or disable delay injection.
       *
       * @param enabled
       *          flag to enable or disable delay injection.
       */
      void injectDelays(boolean enabled);
  
      /**
       * Return the flag indicating if should inject delays.
       *
       * @return true to inject delays otherwise false.
       */
      boolean shouldInjectDelays();
  
      /**
       * Return the injected delay in milliseconds.
       *
       * @return the injected delay in milliseconds.
       */
      int getInjectedDelayMs();
  
      /**
       * Enable or disable injecting stops. This could be used
       * for simulating stopping an action.
       */
      void injectStops(boolean enabled);
  
      /**
       * Return the flag indicating if should inject stops.
       *
       * @return true to inject stops otherwise false.
       */
      boolean shouldInjectStops();
  
      /**
       * Return the flag indicating if should inject corruption.
       *
       * @param startEntryId the start entry id
       * @param endEntryId the end entry id
       * @return true to inject corruption otherwise false.
       */
      boolean shouldInjectCorruption(long startEntryId, long endEntryId);
  
  }
  