Namevalueobjectarchive, Namevalueschema, Objectidentifier – Sun Microsystems Sun StorageTek 5800 User Manual
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For more information on using these classes, see
NameValueObjectArchive
The NameValueObjectArchive class is the main entry point into the 5800 system. Each instance
of NameValueObjectArchive provides access to a specific 5800 system server, functioning as a
proxy object on which operations can be performed. Multiple simultaneous operations can be
accomplished in separate threads on the same NameValueObjectArchive instance.
Communication with the 5800 system server is entirely by means of HTTP requests. A pool of
HTTP connections is maintained for efficiency.
A NameValueObjectArchive instance enables you to store, retrieve, query and delete object
data and associated metadata records. Metadata is associated with an object in a set of
name-value pairs (see
). Metadata records can be used to
associate application-specific information with the raw data, such as name, mime type, or purge
date. Metadata records consist of structured data that can be queried. Object data is opaque to
the 5800 system.
A NameValueObjectArchive instance always ensures that a metadata record is created on the
5800 system server for each newly stored object, even if no metadata is provided with the store.
This enables a model of programming where every stored data object is accessed by name-value
metadata records (for example, for examining results from queries or performing delete
operations). Object data is never deleted directly; it is deleted when its last referencing metadata
record is deleted.
For additional information, see
“NameValueObjectArchive Application Access” on page 30
NameValueSchema
An instance of NameValueSchema represents information about the name-value metadata that
the 5800 system system uses to index data. This instance can be used to enumerate the fields
available in the schema as attributes. Each attribute has a name and a type.
See the Sun StorageTek 5800 System Administrator’s Guide for information on how to define
attributes.
ObjectIdentifier
Instances of ObjectIdentifier uniquely represent objects in a 5800 system store. The 5800
system creates these instances when objects are stored and are returned to the client as part of
the store result.ObjectIdentifier instances can be stored outside of the 5800 system and used
Java API
Chapter 2 • Sun StorageTek 5800 System Java Client API
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