Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. */ package brooklyn.entity.rebind; import java.lang.reflect.Field; import java.util.Collections; import java.util.Map; import java.util.NoSuchElementException; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import brooklyn.config.ConfigKey; import brooklyn.entity.rebind.dto.MementosGenerators; import brooklyn.location.Location; import brooklyn.location.basic.AbstractLocation; import brooklyn.mementos.LocationMemento; import brooklyn.util.collections.MutableMap; import brooklyn.util.flags.FlagUtils; import brooklyn.util.flags.TypeCoercions; import com.google.common.collect.Sets; public class BasicLocationRebindSupport extends AbstractBrooklynObjectRebindSupport<LocationMemento> { private static final Logger LOG = LoggerFactory.getLogger(BasicLocationRebindSupport.class); private final AbstractLocation location; public BasicLocationRebindSupport(AbstractLocation location) { super(location); this.location = location; } // Can rely on super-type once the deprecated getMementoWithProperties is deleted @Override public LocationMemento getMemento() { return getMementoWithProperties(Collections.<String, Object>emptyMap()); } /** * @deprecated since 0.7.0; use generic config/attributes rather than "custom fields", so use {@link #getMemento()} */ @Deprecated protected LocationMemento getMementoWithProperties(Map<String, ?> props) { LocationMemento memento = MementosGenerators.newLocationMementoBuilder(location).customFields(props) .build(); if (LOG.isTraceEnabled()) LOG.trace("Creating memento for location: {}", memento.toVerboseString()); return memento; } @Override protected void addConfig(RebindContext rebindContext, LocationMemento memento) { // FIXME Treat config like we do for entities; this code will disappear when locations become entities. // Note that the flags have been set in the constructor // FIXME Relies on location.config().getLocalBag() being mutable (to modify the location's own config) location.config().getLocalBag().putAll(memento.getLocationConfig()) .markAll(Sets.difference(memento.getLocationConfig().keySet(), memento.getLocationConfigUnused())) .setDescription(memento.getLocationConfigDescription()); for (Map.Entry<String, Object> entry : memento.getLocationConfig().entrySet()) { String flagName = entry.getKey(); try { Field field = FlagUtils.findFieldForFlag(flagName, location); Class<?> fieldType = field.getType(); Object value = entry.getValue(); // Field is either of type ConfigKey, or it's a vanilla java field annotated with @SetFromFlag. // If the former, need to look up the field value (i.e. the ConfigKey) to find out the type. // If the latter, just want to look at the field itself to get the type. // Then coerce the value we have to that type. // And use magic of setFieldFromFlag's magic to either set config or field as appropriate. if (ConfigKey.class.isAssignableFrom(fieldType)) { ConfigKey<?> configKey = (ConfigKey<?>) FlagUtils.getField(location, field); value = TypeCoercions.coerce(entry.getValue(), configKey.getTypeToken()); } else { value = TypeCoercions.coerce(entry.getValue(), fieldType); } if (value != null) { location.config().addToLocalBag(MutableMap.of(flagName, value)); FlagUtils.setFieldFromFlag(location, flagName, value); } } catch (NoSuchElementException e) { // FIXME How to do findFieldForFlag without throwing exception if it's not there? } } } @Override protected void addCustoms(RebindContext rebindContext, LocationMemento memento) { setParent(rebindContext, memento); addChildren(rebindContext, memento); location.init(); // TODO deprecated calling init; will be deleted } @Override public void addFeeds(RebindContext rebindContext, LocationMemento Memento) { throw new UnsupportedOperationException(); } protected void addChildren(RebindContext rebindContext, LocationMemento memento) { for (String childId : memento.getChildren()) { Location child = rebindContext.lookup().lookupLocation(childId); if (child != null) { location.addChild(child); } else { LOG.warn("Ignoring child {} of location {}({}), as cannot be found", new Object[] { childId, memento.getType(), memento.getId() }); } } } protected void setParent(RebindContext rebindContext, LocationMemento memento) { Location parent = (memento.getParent() != null) ? rebindContext.lookup().lookupLocation(memento.getParent()) : null; if (parent != null) { location.setParent(parent); } else if (memento.getParent() != null) { LOG.warn("Ignoring parent {} of location {}({}), as cannot be found", new Object[] { memento.getParent(), memento.getType(), memento.getId() }); } } }