org.alfresco.service.cmr.repository
Interface ContentService

All Known Implementing Classes:
ContentServiceImpl, RoutingContentService

public interface ContentService

Provides methods for accessing and transforming content.

Implementations of this service are primarily responsible for ensuring that the correct store is used to access content, and that reads and writes for the same node reference are routed to the same store instance.

The mechanism for selecting an appropriate store is not prescribed by the interface, but typically the decision will be made on the grounds of content type.

Whereas the content stores have no knowledge of nodes other than their references, the ContentService is responsible for ensuring that all the relevant node-content relationships are maintained.

See Also:
ContentStore, ContentReader, ContentWriter

Method Summary
 java.util.List getActiveTransformers(java.lang.String sourceMimetype, java.lang.String targetMimetype, TransformationOptions options)
          Fetch all the transformers that are capable of transforming the content in the given source mimetype to the given target mimetype with the provided transformation options.
 ContentTransformer getImageTransformer()
          Fetch the transformer that is capable of transforming image content.
 org.alfresco.service.cmr.repository.ContentReader getRawReader(java.lang.String contentUrl)
          Fetch content from the low-level stores using a content URL.
 org.alfresco.service.cmr.repository.ContentReader getReader(org.alfresco.service.cmr.repository.NodeRef nodeRef, org.alfresco.service.namespace.QName propertyQName)
          Gets a reader for the content associated with the given node property.
 long getStoreFreeSpace()
          Gets the remaing available space in the underlying content store.
 long getStoreTotalSpace()
          Gets the total space of the underlying content store (not exclusively Alfresco-controlled binaries).
 org.alfresco.service.cmr.repository.ContentWriter getTempWriter()
          Gets a writer to a temporary location.
 ContentTransformer getTransformer(java.lang.String sourceMimetype, java.lang.String targetMimetype)
          Fetch the transformer that is capable of transforming the content in the given source mimetype to the given target mimetype.
 ContentTransformer getTransformer(java.lang.String sourceMimetype, java.lang.String targetMimetype, TransformationOptions options)
          Fetch the transformer that is capable of transforming the content in the given source mimetype to the given target mimetype with the provided transformation options.
 org.alfresco.service.cmr.repository.ContentWriter getWriter(org.alfresco.service.cmr.repository.NodeRef nodeRef, org.alfresco.service.namespace.QName propertyQName, boolean update)
          Get a content writer for the given node property, choosing to optionally have the node property updated automatically when the content stream closes.
 boolean isTransformable(org.alfresco.service.cmr.repository.ContentReader reader, org.alfresco.service.cmr.repository.ContentWriter writer)
          Returns whether a transformer exists that can read the content from the reader and write the content back out to the writer.
 boolean isTransformable(org.alfresco.service.cmr.repository.ContentReader reader, org.alfresco.service.cmr.repository.ContentWriter writer, TransformationOptions options)
          Returns whether a transformer exists that can read the content from the reader and write the content back out to the writer with the provided tranformation options.
 void transform(org.alfresco.service.cmr.repository.ContentReader reader, org.alfresco.service.cmr.repository.ContentWriter writer)
          Transforms the content from the reader and writes the content back out to the writer.
 void transform(org.alfresco.service.cmr.repository.ContentReader reader, org.alfresco.service.cmr.repository.ContentWriter writer, java.util.Map options)
          Deprecated. 
 void transform(org.alfresco.service.cmr.repository.ContentReader reader, org.alfresco.service.cmr.repository.ContentWriter writer, TransformationOptions options)
           
 

Method Detail

getStoreTotalSpace

long getStoreTotalSpace()
Gets the total space of the underlying content store (not exclusively Alfresco-controlled binaries).

Returns:
Returns the total, possibly approximate, size (in bytes) of of the store or -1 if no size data is available.
Since:
3.3.3

getStoreFreeSpace

long getStoreFreeSpace()
Gets the remaing available space in the underlying content store.

Returns:
Returns the total, possibly approximate, remaining space (in bytes) available to store content or -1 if no size data is available.
Since:
3.3.3

getRawReader

@Auditable(parameters="contentUrl")
org.alfresco.service.cmr.repository.ContentReader getRawReader(java.lang.String contentUrl)
Fetch content from the low-level stores using a content URL. None of the metadata associated with the content will be populated. This method should be used only to stream the binary data out when no other metadata is required.

null is never returned, but the reader should always be checked for existence.

Parameters:
contentUrl - a content store URL
Returns:
Returns a reader for the URL that needs to be checked.

getReader

@Auditable(parameters={"nodeRef", "propertyQName"})
org.alfresco.service.cmr.repository.ContentReader getReader(org.alfresco.service.cmr.repository.NodeRef nodeRef,
                                                                      org.alfresco.service.namespace.QName propertyQName)
                                                            throws org.alfresco.service.cmr.repository.InvalidNodeRefException,
                                                                   org.alfresco.service.cmr.dictionary.InvalidTypeException
Gets a reader for the content associated with the given node property.

If a content URL is present for the given node then a reader must be returned. The exists method should then be used to detect 'missing' content.

Parameters:
nodeRef - a reference to a node having a content property
propertyQName - the name of the property, which must be of type content
Returns:
Returns a reader for the content associated with the node property, or null if no content has been written for the property
Throws:
InvalidNodeRefException - if the node doesn't exist
org.alfresco.service.cmr.dictionary.InvalidTypeException - if the node is not of type content
See Also:
FileContentReader.getSafeContentReader(ContentReader, String, Object[])

getWriter

@Auditable(parameters={"nodeRef", "propertyQName", "update"})
org.alfresco.service.cmr.repository.ContentWriter getWriter(org.alfresco.service.cmr.repository.NodeRef nodeRef,
                                                                      org.alfresco.service.namespace.QName propertyQName,
                                                                      boolean update)
                                                            throws org.alfresco.service.cmr.repository.InvalidNodeRefException,
                                                                   org.alfresco.service.cmr.dictionary.InvalidTypeException
Get a content writer for the given node property, choosing to optionally have the node property updated automatically when the content stream closes.

If the update flag is off, then the state of the node property will remain unchanged regardless of the state of the written binary data. If the flag is on, then the node property will be updated on the same thread as the code that closed the write channel.

If no node is supplied, then the writer will provide a stream into the backing content store, but will not be associated with any new or previous content.

NOTE: The content URL provided will be registered for automatic cleanup in the event that the transaction, in which this method was called, rolls back. If the transaction is successful, the writer may still be open and available for use but the underlying binary will not be cleaned up subsequently. The recommended pattern is to group calls to retrieve the writer in the same transaction as the calls to subsequently update and close the write stream - including setting of the related content properties.

Parameters:
nodeRef - a reference to a node having a content property, or null to just get a valid writer into a backing content store.
propertyQName - the name of the property, which must be of type content
update - true if the property must be updated atomically when the content write stream is closed (attaches a listener to the stream); false if the client code will perform the updates itself.
Returns:
Returns a writer for the content associated with the node property
Throws:
InvalidNodeRefException - if the node doesn't exist
org.alfresco.service.cmr.dictionary.InvalidTypeException - if the node property is not of type content

getTempWriter

@Auditable
org.alfresco.service.cmr.repository.ContentWriter getTempWriter()
Gets a writer to a temporary location. The longevity of the stored temporary content is determined by the system.

Returns:
Returns a writer onto a temporary location

transform

@Auditable(parameters={"reader", "writer"})
void transform(org.alfresco.service.cmr.repository.ContentReader reader,
                         org.alfresco.service.cmr.repository.ContentWriter writer)
               throws NoTransformerException,
                      org.alfresco.service.cmr.repository.ContentIOException
Transforms the content from the reader and writes the content back out to the writer.

The mimetypes used for the transformation must be set both on the reader and on the writer.

Parameters:
reader - the source content location and mimetype
writer - the target content location and mimetype
Throws:
NoTransformerException - if no transformer exists for the given source and target mimetypes of the reader and writer
ContentIOException - if the transformation fails

transform

@Auditable(parameters={"reader", "writer", "options"})
@Deprecated
void transform(org.alfresco.service.cmr.repository.ContentReader reader,
                                    org.alfresco.service.cmr.repository.ContentWriter writer,
                                    java.util.Map options)
               throws NoTransformerException,
                      org.alfresco.service.cmr.repository.ContentIOException
Deprecated. 

Parameters:
reader - the source content location and mimetype
writer - the target content location and mimetype
options - the options for the transformation
Throws:
NoTransformerException - if no transformer exists for the given source and target mimetypes of the reader and writer
ContentIOException - if the transformation fails
See Also:
org.aflresco.service.cmr.repository.ContentService.transform(ContentReader, ContentReader), A map of transform options can be provided.

transform

@Auditable(parameters={"reader", "writer", "options"})
void transform(org.alfresco.service.cmr.repository.ContentReader reader,
                         org.alfresco.service.cmr.repository.ContentWriter writer,
                         TransformationOptions options)
               throws NoTransformerException,
                      org.alfresco.service.cmr.repository.ContentIOException
Parameters:
reader - the source content location and mimetype
writer - the target content location and mimetype
options - the options for the transformation
Throws:
NoTransformerException - if no transformer exists for the given source and target mimetypes of the reader and writer
ContentIOException - if the transformation fails
See Also:
A transformation options can be provided.

getTransformer

@Auditable(parameters={"sourceMimetype", "targetMimetype"})
ContentTransformer getTransformer(java.lang.String sourceMimetype,
                                            java.lang.String targetMimetype)
Fetch the transformer that is capable of transforming the content in the given source mimetype to the given target mimetype.

Since no transformation options are provided only the source and destination mimetypes are considered when getting the correct transformer.

Parameters:
the - source mimetype
the - target mimetype
Returns:
Returns a transformer that can be used, or null if one was not available
See Also:
org.alfresco.service.cmr.respository.ContentService.getTransformer(String, String, TransformationOptions), ContentAccessor.getMimetype()

getTransformer

@Auditable(parameters={"sourceMimetype", "targetMimetype", "options"})
ContentTransformer getTransformer(java.lang.String sourceMimetype,
                                            java.lang.String targetMimetype,
                                            TransformationOptions options)
Fetch the transformer that is capable of transforming the content in the given source mimetype to the given target mimetype with the provided transformation options.

The transformation options provide a finer grain way of discovering the correct transformer, since the values and type of the options provided are considered by the transformer when deciding whether it can satisfy the transformation request.

Parameters:
sourceMimetype - the source mimetype
targetMimetype - the target mimetype
options - the transformation options
Returns:
ContentTransformer a transformer that can be used, or null if one was not available
See Also:
ContentAccessor.getMimetype()

getActiveTransformers

@Auditable(parameters={"sourceMimetype", "targetMimetype", "options"})
java.util.List getActiveTransformers(java.lang.String sourceMimetype,
                                               java.lang.String targetMimetype,
                                               TransformationOptions options)
Fetch all the transformers that are capable of transforming the content in the given source mimetype to the given target mimetype with the provided transformation options.

The transformation options provide a finer grain way of discovering the correct transformer, since the values and type of the options provided are considered by the transformer when deciding whether it can satisfy the transformation request.

The list will contain all currently active, applicable transformers sorted in repository preference order. The contents of this list may change depending on such factors as the availability of particular transformers as well as their current behaviour. For these reasons, this list should not be cached.

Parameters:
sourceMimetype - the source mimetype
targetMimetype - the target mimetype
options - the transformation options
Returns:
ContentTransformers a List of the transformers that can be used, or the empty list if none were available
Since:
3.5
See Also:
ContentAccessor.getMimetype()

getImageTransformer

@Auditable
ContentTransformer getImageTransformer()
Fetch the transformer that is capable of transforming image content.

Returns:
Returns a transformer that can be used, or null if one was not available

isTransformable

@Auditable(parameters={"reader", "writer"})
boolean isTransformable(org.alfresco.service.cmr.repository.ContentReader reader,
                                  org.alfresco.service.cmr.repository.ContentWriter writer)
Returns whether a transformer exists that can read the content from the reader and write the content back out to the writer.

Since no transformation options are specified, only the source and target mimetypes will be considered when making this decision.

The mimetypes used for the transformation must be set both on the reader and on the writer.

Parameters:
reader - the source content location and mimetype
writer - the target content location and mimetype
Returns:
true if a transformer exists, false otherwise
See Also:
org.alfresco.service.cmr.repository.ContentService.isTransformable(ContentReader, ContentWriter, TransformationOptions)

isTransformable

@Auditable(parameters={"reader", "writer", "options"})
boolean isTransformable(org.alfresco.service.cmr.repository.ContentReader reader,
                                  org.alfresco.service.cmr.repository.ContentWriter writer,
                                  TransformationOptions options)
Returns whether a transformer exists that can read the content from the reader and write the content back out to the writer with the provided tranformation options.

The mimetypes used for the transformation must be set both on the reader and on the writer.

Parameters:
reader - the source content location and mimetype
writer - the target content location and mimetype
options - the transformation options
Returns:
boolean true if a transformer exists, false otherwise


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