Package io.bdeploy.bhive.meta

Class MetaManifest<T>

java.lang.Object

io.bdeploy.bhive.meta.MetaManifest<T>

public class MetaManifest<T>
extends Object

A MetaManifest allows to persist an load metadata associated with a given Manifest.

It is possible to put multiple metadata infos on a single Manifest, distinguished by the Class simple name. Each metadata object is stored in a separate blob to allow cheap reading of individual data streams without the need to touch/read any other metadata object.

Field Summary

Fields

Modifier and Type	Field	Description
static final int	META_HIST_SIZE
static final String	META_PREFIX

Constructor Summary

Constructors

Constructor	Description
MetaManifest(Manifest.Key parent, boolean useParentTag, Class<T> metaClazz)	Create a MetaManifest for the given Manifest.Key which identifies the Manifest to "annotate" with metadata.

Method Summary

Modifier and Type	Method	Description
String	getMetaName()
static boolean	isMetaManifest(Manifest.Key meta)
static boolean	isParentAlive(Manifest.Key meta, BHiveExecution hive, SortedSet<Manifest.Key> ignore)
T	read(BHiveExecution source)	Read the current metadata from the given BHiveExecution.
Manifest.Key	remove(BHiveExecution target)	Removes the metadata from the given BHiveExecution.
Manifest.Key	write(BHiveExecution target, T meta)	Writes the given metadata object to the given BHiveExecution.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

META_PREFIX

public static final String META_PREFIX

See Also:

• Constant Field Values

META_HIST_SIZE

public static final int META_HIST_SIZE

See Also:

• Constant Field Values

Constructor Details

MetaManifest

public MetaManifest(Manifest.Key parent,
 boolean useParentTag,
 Class<T> metaClazz)

Create a MetaManifest for the given Manifest.Key which identifies the Manifest to "annotate" with metadata.

Parameters:

parent - the parent Manifests Manifest.Key.

useParentTag - whether the metadata is tag specific or valid for any tag of the given Manifest. Attention: reading and writing must happen with the same parameter. Tag specific metadata is not read by a non-tag specific MetaManifest and vice versa.

metaClazz - the Class of the metadata to store. This Class must be serializable by the StorageHelper.

Method Details

isMetaManifest

public static boolean isMetaManifest(Manifest.Key meta)

isParentAlive

public static boolean isParentAlive(Manifest.Key meta,
 BHiveExecution hive,
 SortedSet<Manifest.Key> ignore)

read

public T read(BHiveExecution source)

Read the current metadata from the given BHiveExecution.

Parameters:

source - the source BHiveExecution

Returns:

The current version of the metadata. null if no metadata for the given Class is present.

write

public Manifest.Key write(BHiveExecution target,
 T meta)

Writes the given metadata object to the given BHiveExecution.

Parameters:

target - the target BHiveExecution

meta - the metadata object. null will cause the entry to be deleted, so subsequent read(io.bdeploy.bhive.BHiveExecution) calls will return null as well.

Returns:

the Manifest.Key of the current metadata manifest.

remove

public Manifest.Key remove(BHiveExecution target)

Removes the metadata from the given BHiveExecution. Convenience shortcut for write(target, null).

Parameters:

target - the target to delete from.

Returns:

the Manifest.Key of the current metadata manifest.

getMetaName

public String getMetaName()