org.alfresco.service.cmr.repository

Interface ContentService

All Known Implementing Classes:

ContentServiceImpl, RoutingContentService

@AlfrescoPublicApi
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.

Author:

Derek Hulley

See Also:

ContentStore, ContentReader, ContentWriter

Method Summary

Modifier and Type	Method and Description
List<ContentTransformer>	getActiveTransformers(String sourceMimetype, long sourceSize, String targetMimetype, TransformationOptions options) Deprecated. use getTransformers(String, String, long, String, TransformationOptions).
List<ContentTransformer>	getActiveTransformers(String sourceMimetype, String targetMimetype, TransformationOptions options) Deprecated. use getTransformers(String, String, long, String, TransformationOptions).
ContentTransformer	getImageTransformer() Fetch the transformer that is capable of transforming image content.
long	getMaxSourceSizeBytes(String sourceMimetype, String targetMimetype, TransformationOptions options) Returns the maximum source size of any content that may transformed between the supplied mimetypes using the supplied options.
org.alfresco.service.cmr.repository.ContentReader	getRawReader(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(String sourceMimetype, String targetMimetype) Fetch the transformer that is capable of transforming the content in the given source mimetype to the given target mimetype.
ContentTransformer	getTransformer(String sourceUrl, String sourceMimetype, long sourceSize, 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.
ContentTransformer	getTransformer(String sourceMimetype, String targetMimetype, TransformationOptions options) Deprecated. use overloaded method with sourceSize parameter.
List<ContentTransformer>	getTransformers(String sourceUrl, String sourceMimetype, long sourceSize, String targetMimetype, TransformationOptions options) Fetch the transformers that are 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) Deprecated. use isTransformable(ContentReader, ContentWriter, TransformationOptions).
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, Map<String,Object> options) Deprecated. As of release 3.0 the TransformOptions class should be used to pass transformation options to a transformation execution.
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(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,
                                                                                 Map<String,Object> options)
                                                                          throws NoTransformerException,
                                                                                 org.alfresco.service.cmr.repository.ContentIOException

Deprecated. As of release 3.0 the TransformOptions class should be used to pass transformation options to a transformation execution.

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:

transform(ContentReader, ContentWriter), 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(String sourceMimetype,
                                                                                             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:

sourceMimetype - the source mimetype

targetMimetype - the target mimetype

Returns:

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

See Also:

getTransformer(String, String, long, String, TransformationOptions), ContentAccessor.getMimetype()

getTransformers

@Auditable(parameters={"sourceMimetype","sourceSize","targetMimetype","options"})
List<ContentTransformer> getTransformers(String sourceUrl,
                                                                                                                           String sourceMimetype,
                                                                                                                           long sourceSize,
                                                                                                                           String targetMimetype,
                                                                                                                           TransformationOptions options)

Fetch 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.

Parameters:

sourceUrl - TODO

sourceMimetype - the source mimetype

sourceSize - the source size (bytes). Ignored if negative.

targetMimetype - the target mimetype

options - the transformation options

Returns:

ContentTransformer the transformers that can be used, or null if none are available

getTransformer

@Auditable(parameters={"sourceMimetype","sourceSize","targetMimetype","options"})
ContentTransformer getTransformer(String sourceUrl,
                                                                                                                    String sourceMimetype,
                                                                                                                    long sourceSize,
                                                                                                                    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:

sourceUrl - TODO

sourceMimetype - the source mimetype

sourceSize - the source size (bytes). Ignored if negative.

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()

getTransformer

ContentTransformer getTransformer(String sourceMimetype,
                                  String targetMimetype,
                                  TransformationOptions options)

Deprecated. use overloaded method with sourceSize parameter.

getMaxSourceSizeBytes

@Auditable(parameters={"sourceMimetype","targetMimetype","options"})
long getMaxSourceSizeBytes(String sourceMimetype,
                                                                                                String targetMimetype,
                                                                                                TransformationOptions options)

Returns the maximum source size of any content that may transformed between the supplied mimetypes using the supplied options.

Parameters:

sourceMimetype - source mime type

targetMimetype - target mime type

options - transformation options

Returns:

0 if there are no transformers, -1 if there is no limit or if positive number the size in bytes.

getActiveTransformers

@Auditable(parameters={"sourceMimetype","sourceSize","targetMimetype","options"})
List<ContentTransformer> getActiveTransformers(String sourceMimetype,
                                                                                                                                 long sourceSize,
                                                                                                                                 String targetMimetype,
                                                                                                                                 TransformationOptions options)

Deprecated. use getTransformers(String, String, long, String, TransformationOptions).

Since:

3.5

getActiveTransformers

List<ContentTransformer> getActiveTransformers(String sourceMimetype,
                                               String targetMimetype,
                                               TransformationOptions options)

Deprecated. use getTransformers(String, String, long, String, TransformationOptions).

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)

Deprecated. use 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.

If you are about to call transform(ContentReader, ContentWriter, TransformationOptions) it is best NOT to call this method first as it must perform the same steps and will throw NoTransformerException if there are no transformers.

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