infra/translate-utils/src/main/java/io/fd/honeycomb/translate/util/write/AbstractGenericWriter.java

   1 /*
   2  * Copyright (c) 2016 Cisco and/or its affiliates.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 package io.fd.honeycomb.translate.util.write;
  18
  19 import io.fd.honeycomb.translate.util.RWUtils;
  20 import io.fd.honeycomb.translate.write.WriteContext;
  21 import io.fd.honeycomb.translate.write.WriteFailedException;
  22 import io.fd.honeycomb.translate.write.Writer;
  23 import org.opendaylight.yangtools.yang.binding.DataObject;
  24 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
  25 import org.slf4j.Logger;
  26 import org.slf4j.LoggerFactory;
  27
  28 import javax.annotation.Nonnull;
  29 import javax.annotation.Nullable;
  30
  31 import static com.google.common.base.Preconditions.checkArgument;
  32
  33 public abstract class AbstractGenericWriter<D extends DataObject> implements Writer<D> {
  34
  35     private static final Logger LOG = LoggerFactory.getLogger(AbstractGenericWriter.class);
  36
  37     private final InstanceIdentifier<D> instanceIdentifier;
  38     private final boolean supportsUpdate;
  39
  40     protected AbstractGenericWriter(final InstanceIdentifier<D> type, final boolean supportsUpdate) {
  41         this.instanceIdentifier = RWUtils.makeIidWildcarded(type);
  42         this.supportsUpdate = supportsUpdate;
  43     }
  44
  45     protected void writeCurrent(final InstanceIdentifier<D> id, final D data, final WriteContext ctx)
  46         throws WriteFailedException {
  47         LOG.debug("{}: Writing current: {} data: {}", this, id, data);
  48         writeCurrentAttributes(id, data, ctx);
  49         LOG.debug("{}: Current node written successfully", this);
  50     }
  51
  52     protected void updateCurrent(final InstanceIdentifier<D> id, final D dataBefore, final D dataAfter,
  53                                  final WriteContext ctx) throws WriteFailedException {
  54         LOG.debug("{}: Updating current: {} dataBefore: {}, datAfter: {}", this, id, dataBefore, dataAfter);
  55
  56         if (dataBefore.equals(dataAfter)) {
  57             LOG.debug("{}: Skipping current(no update): {}", this, id);
  58             // No change, ignore
  59             return;
  60         }
  61         updateCurrentAttributes(id, dataBefore, dataAfter, ctx);
  62         LOG.debug("{}: Current node updated successfully", this);
  63     }
  64
  65     protected void deleteCurrent(final InstanceIdentifier<D> id, final D dataBefore, final WriteContext ctx)
  66         throws WriteFailedException {
  67         LOG.debug("{}: Deleting current: {} dataBefore: {}", this, id, dataBefore);
  68         deleteCurrentAttributes(id, dataBefore, ctx);
  69     }
  70
  71     @SuppressWarnings("unchecked")
  72     @Override
  73     public void processModification(@Nonnull final InstanceIdentifier<? extends DataObject> id,
  74                                     @Nullable final DataObject dataBefore,
  75                                     @Nullable final DataObject dataAfter,
  76                                     @Nonnull final WriteContext ctx) throws WriteFailedException {
  77         LOG.debug("{}: Updating : {}", this, id);
  78         LOG.trace("{}: Updating : {}, from: {} to: {}", this, id, dataBefore, dataAfter);
  79
  80         checkArgument(idPointsToCurrent(id), "Cannot handle data: %s. Only: %s can be handled by writer: %s",
  81                 id, getManagedDataObjectType(), this);
  82
  83         if (isWrite(dataBefore, dataAfter)) {
  84             writeCurrent((InstanceIdentifier<D>) id, castToManaged(dataAfter), ctx);
  85         } else if (isDelete(dataBefore, dataAfter)) {
  86             deleteCurrent((InstanceIdentifier<D>) id, castToManaged(dataBefore), ctx);
  87         } else {
  88             checkArgument(dataBefore != null && dataAfter != null, "No data to process");
  89             updateCurrent((InstanceIdentifier<D>) id, castToManaged(dataBefore), castToManaged(dataAfter), ctx);
  90         }
  91     }
  92
  93     private void checkDataType(@Nonnull final DataObject dataAfter) {
  94         checkArgument(getManagedDataObjectType().getTargetType().isAssignableFrom(dataAfter.getClass()));
  95     }
  96
  97     private D castToManaged(final DataObject data) {
  98         checkDataType(data);
  99         return getManagedDataObjectType().getTargetType().cast(data);
 100     }
 101
 102     private static boolean isWrite(final DataObject dataBefore,
 103                                     final DataObject dataAfter) {
 104         return dataBefore == null && dataAfter != null;
 105     }
 106
 107     private static boolean isDelete(final DataObject dataBefore,
 108                                     final DataObject dataAfter) {
 109         return dataAfter == null && dataBefore != null;
 110     }
 111
 112     private boolean idPointsToCurrent(final @Nonnull InstanceIdentifier<? extends DataObject> id) {
 113         return id.getTargetType().equals(getManagedDataObjectType().getTargetType());
 114     }
 115
 116     protected abstract void writeCurrentAttributes(@Nonnull final InstanceIdentifier<D> id,
 117                                                    @Nonnull final D data,
 118                                                    @Nonnull final WriteContext ctx) throws WriteFailedException;
 119
 120     protected abstract void deleteCurrentAttributes(@Nonnull final InstanceIdentifier<D> id,
 121                                                     @Nonnull final D dataBefore,
 122                                                     @Nonnull final WriteContext ctx) throws WriteFailedException;
 123
 124     protected abstract void updateCurrentAttributes(@Nonnull final InstanceIdentifier<D> id,
 125                                                     @Nonnull final D dataBefore,
 126                                                     @Nonnull final D dataAfter,
 127                                                     @Nonnull final WriteContext ctx) throws WriteFailedException;
 128
 129     @Nonnull
 130     @Override
 131     public InstanceIdentifier<D> getManagedDataObjectType() {
 132         return instanceIdentifier;
 133     }
 134
 135
 136     @Override
 137     public String toString() {
 138         return String.format("Writer[%s]", getManagedDataObjectType().getTargetType().getSimpleName());
 139     }
 140
 141     @Override
 142     public boolean supportsDirectUpdate() {
 143         return supportsUpdate;
 144     }
 145 }