org.apache.brooklyn.api.entity.Entity Maven / Gradle / Ivy
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* 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 org.apache.brooklyn.api.entity;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map;
import javax.annotation.Nullable;
import org.apache.brooklyn.api.effector.Effector;
import org.apache.brooklyn.api.location.Location;
import org.apache.brooklyn.api.mgmt.Task;
import org.apache.brooklyn.api.objs.BrooklynObject;
import org.apache.brooklyn.api.objs.EntityAdjunct;
import org.apache.brooklyn.api.policy.Policy;
import org.apache.brooklyn.api.policy.PolicySpec;
import org.apache.brooklyn.api.sensor.AttributeSensor;
import org.apache.brooklyn.api.sensor.Enricher;
import org.apache.brooklyn.api.sensor.EnricherSpec;
import org.apache.brooklyn.api.sensor.Feed;
import org.apache.brooklyn.api.sensor.Sensor;
import org.apache.brooklyn.api.sensor.SensorEvent;
import org.apache.brooklyn.config.ConfigKey;
import org.apache.brooklyn.config.ConfigKey.HasConfigKey;
import org.apache.brooklyn.util.guava.Maybe;
import com.google.common.annotations.Beta;
import com.google.common.base.Function;
/**
* The basic interface for a Brooklyn entity.
*
* Implementors of entities are strongly encouraged to extend {@link org.apache.brooklyn.core.entity.AbstractEntity}.
*
* To instantiate an entity, see {@code managementContext.getEntityManager().createEntity(entitySpec)}.
* Also see {@link org.apache.brooklyn.core.entity.factory.ApplicationBuilder},
* {@link org.apache.brooklyn.core.entity.AbstractEntity#addChild(EntitySpec)}, and
* {@link org.apache.brooklyn.api.entity.EntitySpec}.
*
*
* @see org.apache.brooklyn.core.entity.AbstractEntity
*/
public interface Entity extends BrooklynObject {
/**
* The unique identifier for this entity.
*/
@Override
String getId();
/**
* Returns the creation time for this entity, in UTC.
*/
long getCreationTime();
/**
* A display name; recommended to be a concise single-line description.
*/
String getDisplayName();
/**
* A URL pointing to an image which can be used to represent this entity.
*/
@Nullable String getIconUrl();
/**
* Information about the type of this entity; analogous to Java's object.getClass.
*/
EntityType getEntityType();
/**
* @return the {@link Application} this entity is registered with, or null if not registered.
*/
Application getApplication();
/**
* @return the id of the {@link Application} this entity is registered with, or null if not registered.
*/
String getApplicationId();
/**
* The parent of this entity, null if no parent.
*
* The parent is normally the entity responsible for creating/destroying/managing this entity.
*
* @see #setParent(Entity)
* @see #clearParent
*/
Entity getParent();
/**
* Return the entities that are children of (i.e. "owned by") this entity
*/
Collection getChildren();
/**
* Sets the entity's display name.
*/
void setDisplayName(String displayName);
/**
* Sets the parent (i.e. "owner") of this entity. Returns this entity, for convenience.
*
* @see #getParent
* @see #clearParent
*/
Entity setParent(Entity parent);
/**
* Clears the parent (i.e. "owner") of this entity. Also cleans up any references within its parent entity.
*
* @see #getParent
* @see #setParent
*/
void clearParent();
/**
* Add a child {@link Entity}, and set this entity as its parent,
* returning the added child.
*
* As with {@link #addChild(EntitySpec)} the child is not brought under management
* as part of this call. It should not be managed prior to this call either.
*/
T addChild(T child);
/**
* Creates an {@link Entity} from the given spec and adds it, setting this entity as the parent,
* returning the added child.
*
* The added child is not managed as part of this call, even if the parent is managed,
* so if adding post-management an explicit call to manage the child will be needed;
* see the convenience method Entities.manage(...)
.
* */
T addChild(EntitySpec spec);
/**
* Removes the specified child {@link Entity}; its parent will be set to null.
*
* @return True if the given entity was contained in the set of children
*/
boolean removeChild(Entity child);
/**
* @return an immutable thread-safe view of the policies.
*
* @deprecated since 0.9.0; see {@link PolicySupport#getPolicies()}
*/
@Deprecated
Collection getPolicies();
/**
* @return an immutable thread-safe view of the enrichers.
*
* @deprecated since 0.9.0; see {@link EnricherSupport#getEnrichers()}
*/
@Deprecated
Collection getEnrichers();
/**
* The {@link Collection} of {@link Group}s that this entity is a member of.
*
* Groupings can be used to allow easy management/monitoring of a group of entities.
*
* @deprecated since 0.9.0; see {@link GroupSupport#getGroups()} and {@link #groups()}
*/
@Deprecated
Collection getGroups();
/**
* Add this entity as a member of the given {@link Group}. Called by framework.
*
* Users should call {@link Group#addMember(Entity)} instead; this method will then
* automatically be called. However, the reverse is not true (calling this method will
* not tell the group; this behaviour may change in a future release!)
*
* @deprecated since 0.9.0; see {@link GroupSupport#add()} and {@link #groups()}
*/
@Deprecated
void addGroup(Group group);
/**
* Removes this entity as a member of the given {@link Group}. Called by framework.
*
* Users should call {@link Group#removeMember(Entity)} instead; this method will then
* automatically be called. However, the reverse is not true (calling this method will
* not tell the group; this behaviour may change in a future release!)
*
* @deprecated since 0.9.0; see {@link GroupSupport#remove()} and {@link #groups()}
*/
@Deprecated
void removeGroup(Group group);
/**
* Return all the {@link Location}s this entity is deployed to.
*/
Collection getLocations();
/**
* Convenience for calling {@link SensorSupport#get(AttributeSensor)},
* via code like {@code sensors().get(key)}.
*/
T getAttribute(AttributeSensor sensor);
/**
* @see {@link #getConfig(ConfigKey)}
*/
T getConfig(HasConfigKey key);
/**
* Invokes the given effector, with the given parameters to that effector.
*/
Task invoke(Effector eff, Map parameters);
/**
* Adds the given policy to this entity. Also calls policy.setEntity if available.
*
* @deprecated since 0.9.0; see {@link PolicySupport#add(Policy)}
*/
@Deprecated
void addPolicy(Policy policy);
/**
* Adds the given policy to this entity. Also calls policy.setEntity if available.
*
* @deprecated since 0.9.0; see {@link PolicySupport#add(PolicySpec)}
*/
@Deprecated
T addPolicy(PolicySpec policy);
/**
* Removes the given policy from this entity.
* @return True if the policy existed at this entity; false otherwise
*
* @deprecated since 0.9.0; see {@link PolicySupport#remove(Policy)}
*/
@Deprecated
boolean removePolicy(Policy policy);
/**
* Adds the given enricher to this entity. Also calls enricher.setEntity if available.
*
* @deprecated since 0.9.0; see {@link EnricherSupport#add(Enricher)}
*/
@Deprecated
void addEnricher(Enricher enricher);
/**
* Adds the given enricher to this entity. Also calls enricher.setEntity if available.
*
* @deprecated since 0.9.0; see {@link EnricherSupport#add(EnricherSpec)}
*/
@Deprecated
T addEnricher(EnricherSpec enricher);
/**
* Removes the given enricher from this entity.
* @return True if the policy enricher at this entity; false otherwise
*
* @deprecated since 0.9.0; see {@link EnricherSupport#remove(Enricher)}
*/
@Deprecated
boolean removeEnricher(Enricher enricher);
/**
* Adds the given feed to this entity. Also calls feed.setEntity if available.
*/
T addFeed(T feed);
SensorSupport sensors();
PolicySupport policies();
EnricherSupport enrichers();
GroupSupport groups();
@Override
RelationSupport relations();
@Beta
public interface SensorSupport {
/**
* Gets the value of the given attribute on this entity, or null if has not been set.
*
* Attributes can be things like workrate and status information, as well as
* configuration (e.g. url/jmxHost/jmxPort), etc.
*/
T get(AttributeSensor key);
/**
* Sets the {@link AttributeSensor} data for the given attribute to the specified value.
*
* This can be used to "enrich" the entity, such as adding aggregated information,
* rolling averages, etc.
*
* @return the old value for the attribute (possibly {@code null})
*/
T set(AttributeSensor attribute, T val);
/**
* Atomically modifies the {@link AttributeSensor}, ensuring that only one modification is done
* at a time.
*
* If the modifier returns {@link Maybe#absent()} then the attribute will be
* left unmodified, and the existing value will be returned.
*
* For details of the synchronization model used to achieve this, refer to the underlying
* attribute store (e.g. AttributeMap).
*
* @return the old value for the attribute (possibly {@code null})
* @since 0.7.0-M2
*/
@Beta
T modify(AttributeSensor attribute, Function super T, Maybe> modifier);
/**
* Emits a {@link SensorEvent} event on behalf of this entity (as though produced by this entity).
*
* Note that for attribute sensors it is nearly always recommended to use setAttribute,
* as this method will not update local values.
*/
void emit(Sensor sensor, T value);
}
public interface AdjunctSupport extends Iterable {
/**
* @return A read-only thread-safe iterator over all the instances.
*/
Iterator iterator();
int size();
boolean isEmpty();
/**
* Adds an instance.
*/
void add(T val);
/**
* Removes an instance.
*/
boolean remove(T val);
}
@Beta
public interface PolicySupport extends AdjunctSupport {
/**
* Adds the given policy to this entity. Also calls policy.setEntity if available.
*/
@Override
void add(Policy policy);
/**
* Removes the given policy from this entity.
* @return True if the policy existed at this entity; false otherwise
*/
@Override
boolean remove(Policy policy);
/**
* Adds the given policy to this entity. Also calls policy.setEntity if available.
*/
T add(PolicySpec enricher);
}
@Beta
public interface EnricherSupport extends AdjunctSupport {
/**
* Adds the given enricher to this entity. Also calls enricher.setEntity if available.
*/
@Override
void add(Enricher enricher);
/**
* Removes the given enricher from this entity.
* @return True if the policy enricher at this entity; false otherwise
*/
@Override
boolean remove(Enricher enricher);
/**
* Adds the given enricher to this entity. Also calls enricher.setEntity if available.
*/
T add(EnricherSpec enricher);
}
/**
* For managing/querying the group membership of this entity.
*
* Groupings can be used to allow easy management/monitoring of a group of entities.
*
* To add/remove this entity from a group, users should call {@link Group#addMember(Entity)}
* and {@link Group#removeMember(Entity)}. In a future release, add/remove methods may be
* added here.
*/
@Beta
public interface GroupSupport extends Iterable {
/**
* A read-only thread-safe iterator over all the {@link Group}s that this entity is a member of.
*/
@Override
Iterator iterator();
int size();
boolean isEmpty();
}
}