org.alfresco.service.cmr.attributes

Interface AttributeService

All Known Implementing Classes:

AttributeServiceImpl

@AlfrescoPublicApi
public interface AttributeService

This provides services for reading, writing, and querying global attributes.

Attributes are uniquely identified by up to 3 keys; null keys are themselves treated uniquely i.e. ['a','b'] is equivalent to ['a','b',null] in all cases except where multiple search results are possible. Keys can be any simple Serializable type, typically being convertable using DefaultTypeConverter. The attribute values persisted can be any Serializable (including collections) but the raw values should be convertable by the DefaultTypeConverter for the most efficient persistence.

Since:

3.4

Author:

Derek Hulley

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	AttributeService.AttributeQueryCallback Callback used for querying for lists of attributes.

Method Summary

Modifier and Type	Method and Description
void	createAttribute(Serializable value, Serializable... keys) Create an attribute with an optional value, assuming there is no existing attribute using the same keys.
boolean	exists(Serializable... keys) Determine if a particular attribute exists.
Serializable	getAttribute(Serializable... keys) Get an attribute using a list of unique keys
void	getAttributes(AttributeService.AttributeQueryCallback callback, Serializable... keys) Get all attributes that share the starter keys provided.
void	removeAttribute(Serializable... keys) Remove a specific attribute.
void	removeAttributes(Serializable... keys) Remove all attributes that share a set of keys (in order)
void	setAttribute(Serializable value, Serializable... keys) Set an attribute, overwriting its prior value if it already existed.
void	updateOrCreateAttribute(Serializable keyBefore1, Serializable keyBefore2, Serializable keyBefore3, Serializable keyAfter1, Serializable keyAfter2, Serializable keyAfter3) Update an attribute key whilst preserving the associated value (if any).

Method Detail

exists

boolean exists(Serializable... keys)

Determine if a particular attribute exists.

Parameters:

keys - List of 1 to 3 keys to uniquely identify the attribute

Returns:

true if the attribute exists (regardless of its value) or false if it doesn't exist

getAttribute

Serializable getAttribute(Serializable... keys)

Get an attribute using a list of unique keys

Parameters:

keys - List of 1 to 3 keys to uniquely identify the attribute

Returns:

The attribute value or null

getAttributes

void getAttributes(AttributeService.AttributeQueryCallback callback,
                   Serializable... keys)

Get all attributes that share the starter keys provided. If 3 key values are given, there can be, at most, one result.

Parameters:

callback - the callback that handles the results

keys - 0 to 3 key values to search against

setAttribute

void setAttribute(Serializable value,
                  Serializable... keys)

Set an attribute, overwriting its prior value if it already existed. null values are treated as unique i.e. if the value set is null then exists(Serializable...) will still return true. If the attribute doesn't exist, it will be created otherwise it will be modified.

Parameters:

value - The value to store (can be a collection or null)

keys - List of 1 to 3 keys to uniquely identify the attribute

createAttribute

void createAttribute(Serializable value,
                     Serializable... keys)

Create an attribute with an optional value, assuming there is no existing attribute using the same keys.

Parameters:

value - The value to store (can be a collection or null)

keys - List of 1 to 3 keys to uniquely identify the attribute

Throws:

DuplicateAttributeException - if the attribute already exists

updateOrCreateAttribute

void updateOrCreateAttribute(Serializable keyBefore1,
                             Serializable keyBefore2,
                             Serializable keyBefore3,
                             Serializable keyAfter1,
                             Serializable keyAfter2,
                             Serializable keyAfter3)

Update an attribute key whilst preserving the associated value (if any). If there is no existing key matching the original value, then nothing will happen.

Parameters:

keyBefore1 - the first part of the original unique key (never null)

keyBefore2 - the second part of the original unique key (null allowed)

keyBefore3 - the third part of the original unique key (null allowed)

keyAfter1 - the first part of the new unique key (never null)

keyAfter2 - the second part of the new unique key (null allowed)

keyAfter3 - the third part of the new unique key (null allowed)

removeAttribute

void removeAttribute(Serializable... keys)

Remove a specific attribute.

Parameters:

keys - up to 3 keys to uniquely identify the attribute

removeAttributes

void removeAttributes(Serializable... keys)

Remove all attributes that share a set of keys (in order)

Parameters:

keys - up to 3 keys to identify attributes to remove