opendaylight/netconf/config-persister-impl/src/main/java/org/opendaylight/controller/netconf/persist/impl/PersisterImpl.java

   1 /*
   2  * Copyright (c) 2013 Cisco Systems, Inc. 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
   9 package org.opendaylight.controller.netconf.persist.impl;
  10
  11 import com.google.common.annotations.VisibleForTesting;
  12 import com.google.common.base.Optional;
  13 import org.opendaylight.controller.config.persist.api.Persister;
  14 import org.opendaylight.controller.config.persist.api.storage.StorageAdapter;
  15 import org.opendaylight.controller.config.persist.api.storage.StorageAdapter.PropertiesProvider;
  16 import org.opendaylight.controller.netconf.persist.impl.osgi.ConfigPersisterActivator;
  17
  18 import java.io.IOException;
  19
  20 /**
  21  * {@link Persister} implementation that delegates persisting functionality to
  22  * underlying {@link Persister} called Storage Adapter.
  23  *
  24  * Storage adapters are low level persisters that do the heavy lifting for this
  25  * class. Instances of storage adapters can be injected directly via constructor
  26  * or instantiated from a full name of its class provided in a properties file.
  27  *
  28  * Name of storage adapter class should be located under
  29  * {@link #STORAGE_ADAPTER_CLASS_PROP} key.
  30  */
  31 public final class PersisterImpl implements Persister {
  32
  33
  34     private final StorageAdapter storage;
  35
  36     public PersisterImpl(StorageAdapter storage) {
  37         this.storage = storage;
  38     }
  39
  40     public static PersisterImpl createFromProperties(PropertiesProvider propertiesProvider) {
  41         String storageAdapterClass = propertiesProvider.getProperty(ConfigPersisterActivator.STORAGE_ADAPTER_CLASS_PROP_SUFFIX);
  42         StorageAdapter storage;
  43         if (storageAdapterClass == null || storageAdapterClass.equals("")) {
  44             throw new IllegalStateException("No persister is defined in " +
  45                     propertiesProvider.getFullKeyForReporting(ConfigPersisterActivator.STORAGE_ADAPTER_CLASS_PROP_SUFFIX)
  46                     + " property. For noop persister use " + NoOpStorageAdapter.class.getCanonicalName()
  47                     + " . Persister is not operational");
  48         }
  49
  50         try {
  51             Class<?> clazz = Class.forName(storageAdapterClass);
  52             boolean implementsCorrectIfc = StorageAdapter.class.isAssignableFrom(clazz);
  53             if (implementsCorrectIfc == false) {
  54                 throw new IllegalArgumentException("Storage adapter " + clazz + " does not implement " + StorageAdapter.class);
  55             }
  56             storage = StorageAdapter.class.cast(clazz.newInstance());
  57
  58             storage.setProperties(propertiesProvider);
  59
  60         } catch (InstantiationException | IllegalAccessException | ClassNotFoundException e) {
  61             throw new IllegalArgumentException("Unable to instantiate storage adapter from " + storageAdapterClass, e);
  62         }
  63
  64         return new PersisterImpl(storage);
  65     }
  66
  67     @Override
  68     public void persistConfig(ConfigSnapshotHolder holder) throws IOException {
  69         storage.persistConfig(holder);
  70     }
  71
  72     @Override
  73     public Optional<ConfigSnapshotHolder> loadLastConfig() throws IOException {
  74         return storage.loadLastConfig();
  75     }
  76
  77     @VisibleForTesting
  78     StorageAdapter getStorage() {
  79         return storage;
  80     }
  81
  82     @Override
  83     public void close() throws IOException {
  84         storage.close();
  85     }
  86
  87     @Override
  88     public String toString() {
  89         return "PersisterImpl [storage=" + storage + "]";
  90     }
  91 }