brooklyn.internal.storage
[Java] Interface BrooklynStorage

public interface BrooklynStorage

getMap

public java.util.concurrent.ConcurrentMap getMap(java.lang.String id)

Creates a map backed by the storage-medium. If a map with this name has already been created, then that existing map will be returned. The returned map is a live view: changes made to the map will be persisted, and changes that others make will be reflected in the map. The map is thread-safe: java.util.Map#keySet() etc will iterate over a snapshot view of the contents.

Parameters:

id

getNonConcurrentList

@Beta
public Reference getNonConcurrentList(java.lang.String id)

Creates a list backed by the storage-medium. If a list with this name has already been created, then that existing list will be returned. The returned list is not a live view. Changes are made by calling reference.set(), and the view is refreshed by calling reference.get(). Changes are thread-safe, but callers must be careful not to overwrite other's changes. For example, the code below could overwrite another threads changes that are made to the map between the call to get() and the subsequent call to set().

 Reference> ref = storage.createNonConcurrentList("myid");
 List newval = ImmutableList.builder().addAll(ref.get()).add("another").builder();
 ref.set(newval);
 
 

TODO Aled says: Is getNonConcurrentList necessary? The purpose of this method, rather than just using Reference ref = getReference(id); ref.set(ImmutableList.of()) is to allow control of the serialization of the things inside the list (e.g. switching the Location object to serialize a proxy object of some sort). I don't want us to have to do deep inspection of every object being added to any map/ref. Feels like we can use normal serialization unless the top-level object matches an instanceof for special things like Entity, Location, etc. Peter responds: What I'm a bit scared of is that we need to write some kind of meta serialization mechanism on top of the mechanisms provided by e.g. Hazelcast or Infinispan. Hazelcast has a very extensive serialization library where you can plug in all kinds of serialization mechanisms.

Parameters:

id

getReference

public Reference getReference(java.lang.String id)

Creates a reference to a value, backed by the storage-medium. If a reference with this name has already been created, then that existing reference will be returned. The returned reference is a live view: changes made to the reference will be persisted, and changes that others make will be reflected in the reference. The reference is thread-safe. No additional synchronization is required when getting/setting the reference.

Parameters:

id

remove

public void remove(java.lang.String id)

Removes the data stored against this id, whether it is a map, ref or whatever.

terminate

public void terminate()

Terminates the BrooklynStorage.

Brooklyn Multi-Cloud Application Management Platform
brooklyncentral.github.com. Apache License. © 2012.