ecomp-portal-BE-common/src/main/java/org/openecomp/portalapp/portal/utils/ParallelExecutor.java

   1 /*-\r
   2  * ================================================================================\r
   3  * ECOMP Portal\r
   4  * ================================================================================\r
   5  * Copyright (C) 2017 AT&T Intellectual Property\r
   6  * ================================================================================\r
   7  * Licensed under the Apache License, Version 2.0 (the "License");\r
   8  * you may not use this file except in compliance with the License.\r
   9  * You may obtain a copy of the License at\r
  10  * \r
  11  *      http://www.apache.org/licenses/LICENSE-2.0\r
  12  * \r
  13  * Unless required by applicable law or agreed to in writing, software\r
  14  * distributed under the License is distributed on an "AS IS" BASIS,\r
  15  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\r
  16  * See the License for the specific language governing permissions and\r
  17  * limitations under the License.\r
  18  * ================================================================================\r
  19  */\r
  20 package org.openecomp.portalapp.portal.utils;\r
  21 \r
  22 import java.util.ArrayList;\r
  23 import java.util.List;\r
  24 import java.util.concurrent.Callable;\r
  25 import java.util.concurrent.ExecutorService;\r
  26 import java.util.concurrent.Executors;\r
  27 import java.util.concurrent.Future;\r
  28 \r
  29 import org.openecomp.portalsdk.core.logging.logic.EELFLoggerDelegate;\r
  30 \r
  31 public abstract class ParallelExecutor<T> {\r
  32 \r
  33         EELFLoggerDelegate logger = EELFLoggerDelegate.getLogger(ParallelExecutor.class);\r
  34 \r
  35         protected static abstract class ThreadOperation<T> {\r
  36                 public abstract T execute(List<Object> parms);\r
  37         }\r
  38 \r
  39         protected abstract ThreadOperation<T> getThreadOperation();\r
  40 \r
  41         private static class CallableOperationThread<T> implements Callable<T> {\r
  42 \r
  43                 List<Object> parms;\r
  44 \r
  45                 private ThreadOperation<T> operation;\r
  46 \r
  47                 public CallableOperationThread(ThreadOperation<T> operation, List<Object> parms) {\r
  48                         this.parms = parms;\r
  49                         this.operation = operation;\r
  50                 }\r
  51 \r
  52                 @Override\r
  53                 public T call() throws Exception {\r
  54                         return this.operation.execute(this.parms);\r
  55                 }\r
  56 \r
  57         }\r
  58 \r
  59         public List<T> performAllOperations(int ThreadPoolSize, List<List<Object>> listOfParms) {\r
  60                 List<T> result = new ArrayList<T>();\r
  61                 if (ThreadPoolSize > 0 && listOfParms != null) {\r
  62                         ExecutorService executor = Executors.newFixedThreadPool(ThreadPoolSize);\r
  63                         List<Future<T>> list = new ArrayList<Future<T>>();\r
  64                         for (List<Object> parms : listOfParms) {\r
  65                                 CallableOperationThread<T> getter = new CallableOperationThread<T>(this.getThreadOperation(), parms);\r
  66                                 Future<T> submit = executor.submit(getter);\r
  67                                 list.add(submit);\r
  68                         }\r
  69                         for (Future<T> future : list) {\r
  70                                 try {\r
  71                                         if (future != null) {\r
  72                                                 result.add(future.get());\r
  73                                         }\r
  74                                 } catch (Exception e) {\r
  75                                         logger.error(EELFLoggerDelegate.errorLogger, EcompPortalUtils.getStackTrace(e));\r
  76                                 }\r
  77                         }\r
  78                         executor.shutdown();\r
  79                 }\r
  80                 return result;\r
  81         }\r
  82 \r
  83 }\r