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

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