opendaylight/md-sal/sal-dom-compat/src/main/java/org/opendaylight/controller/sal/core/compat/AbstractDOMRpcResultFutureAdapter.java

   1 /*
   2  * Copyright (c) 2018 Inocybe Technologies and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.controller.sal.core.compat;
   9
  10 import com.google.common.util.concurrent.AbstractFuture;
  11 import com.google.common.util.concurrent.ListenableFuture;
  12 import java.util.Optional;
  13 import java.util.concurrent.ExecutionException;
  14 import java.util.concurrent.Executor;
  15 import java.util.concurrent.TimeUnit;
  16 import java.util.concurrent.TimeoutException;
  17 import org.opendaylight.mdsal.dom.api.DOMRpcException;
  18 import org.opendaylight.mdsal.dom.api.DOMRpcResult;
  19 import org.opendaylight.yangtools.util.concurrent.ExceptionMapper;
  20
  21 /**
  22  * Base for a DOMRpcResult future adapter.
  23  *
  24  * @author Thomas Pantelis
  25  */
  26 @Deprecated
  27 @SuppressWarnings("checkstyle:ClassTypeParameterName")
  28 public abstract class AbstractDOMRpcResultFutureAdapter<T extends DOMRpcResult, F extends DOMRpcResult,
  29         D extends ListenableFuture<F>, E extends DOMRpcException> extends AbstractFuture<T> {
  30     private final D delegate;
  31     private final ExceptionMapper<E> exMapper;
  32     private volatile Optional<T> result;
  33
  34     AbstractDOMRpcResultFutureAdapter(D delegate, ExceptionMapper<E> exMapper) {
  35         this.delegate = delegate;
  36         this.exMapper = exMapper;
  37     }
  38
  39     protected abstract T transform(F fromResult);
  40
  41     public D delegate() {
  42         return delegate;
  43     }
  44
  45     @Override
  46     public void addListener(Runnable listener, Executor executor) {
  47         delegate.addListener(listener, executor);
  48     }
  49
  50     @Override
  51     public boolean cancel(boolean mayInterruptIfRunning) {
  52         return delegate.cancel(mayInterruptIfRunning);
  53     }
  54
  55     @Override
  56     public boolean isCancelled() {
  57         return delegate.isCancelled();
  58     }
  59
  60     @Override
  61     public boolean isDone() {
  62         return delegate.isDone();
  63     }
  64
  65     @Override
  66     public T get() throws InterruptedException, ExecutionException {
  67         if (result != null) {
  68             return result.orElse(null);
  69         }
  70
  71         try {
  72             return transformIfNecessary(delegate.get());
  73         } catch (ExecutionException e) {
  74             throw new ExecutionException(e.getMessage(), exMapper.apply(e));
  75         }
  76     }
  77
  78     @Override
  79     public T get(final long timeout, final TimeUnit unit) throws InterruptedException, ExecutionException,
  80             TimeoutException {
  81         if (result != null) {
  82             return result.orElse(null);
  83         }
  84
  85         try {
  86             return transformIfNecessary(delegate.get(timeout, unit));
  87         } catch (ExecutionException e) {
  88             throw new ExecutionException(e.getMessage(), exMapper.apply(e));
  89         }
  90     }
  91
  92     private synchronized T transformIfNecessary(F delegateResult) {
  93         if (result == null) {
  94             if (delegateResult == null) {
  95                 result = Optional.empty();
  96             } else {
  97                 result = Optional.of(transform(delegateResult));
  98             }
  99         }
 100
 101         return result.orElse(null);
 102     }
 103 }