org.alfresco.repo.content.filestore

Class FileContentReader

java.lang.Object

org.alfresco.repo.content.AbstractContentAccessor

org.alfresco.repo.content.AbstractContentReader

org.alfresco.repo.content.filestore.FileContentReader

All Implemented Interfaces:

org.alfresco.service.cmr.repository.ContentAccessor, org.alfresco.service.cmr.repository.ContentReader, org.alfresco.service.cmr.repository.FileContentReader

@AlfrescoPublicApi
public class FileContentReader
extends AbstractContentReader
implements org.alfresco.service.cmr.repository.FileContentReader

Provides direct access to a local file.

This class does not provide remote access to the file.

Author:

Derek Hulley

Nested Class Summary

Nested classes/interfaces inherited from class org.alfresco.repo.content.AbstractContentAccessor

AbstractContentAccessor.CallbackFileChannel, AbstractContentAccessor.ChannelCloseCallbackAdvise

Field Summary

Fields

Modifier and Type	Field and Description
static String	MSG_MISSING_CONTENT message key for missing content.

Constructor Summary

Constructors

Constructor and Description
FileContentReader(File file) Constructor that builds a URL based on the absolute path of the file.
FileContentReader(File file, String url) Constructor that explicitely sets the URL that the reader represents.

Method Summary

Modifier and Type	Method and Description
boolean	canWrite() Deprecated. Since 5.1. This method has no value: a file reader can never write (DH: 2015/02/17)
protected org.alfresco.service.cmr.repository.ContentReader	createReader() The URL of the write is known from the start and this method contract states that no consideration needs to be taken w.r.t.
boolean	exists()
protected ReadableByteChannel	getDirectReadableChannel() Provides low-level access to read content from the repository.
File	getFile()
long	getLastModified()
static org.alfresco.service.cmr.repository.ContentReader	getSafeContentReader(org.alfresco.service.cmr.repository.ContentReader existingReader, String msgTemplate, Object... args) Checks the existing reader provided and replaces it with a reader onto some fake content if required.
long	getSize()

Methods inherited from class org.alfresco.repo.content.AbstractContentReader

addListener, compareContentReaders, getContent, getContent, getContentInputStream, getContentString, getContentString, getFileChannel, getLimits, getReadableChannel, getReader, getTransformerDebug, getUseBufferedInputStream, isChannelOpen, isClosed, setLimits, setTransformerDebug, setUseBufferedInputStream

Methods inherited from class org.alfresco.repo.content.AbstractContentAccessor

channelOpened, finalize, getCallbackFileChannel, getContentData, getContentUrl, getEncoding, getLocale, getMimetype, setContentUrl, setEncoding, setLocale, setMimetype, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.alfresco.service.cmr.repository.ContentReader

getContent, getContent, getContentInputStream, getContentString, getContentString, getFileChannel, getReadableChannel, getReader, isClosed

Methods inherited from interface org.alfresco.service.cmr.repository.ContentAccessor

addListener, getContentData, getContentUrl, getEncoding, getLocale, getMimetype, isChannelOpen, setEncoding, setLocale, setMimetype

Field Detail

MSG_MISSING_CONTENT

public static final String MSG_MISSING_CONTENT

message key for missing content. Parameters are

• NodeRef
• ContentReader

See Also:

Constant Field Values

Constructor Detail

FileContentReader

public FileContentReader(File file)

Constructor that builds a URL based on the absolute path of the file.

Parameters:

file - the file for reading. This will most likely be directly related to the content URL.

FileContentReader

public FileContentReader(File file,
                         String url)

Constructor that explicitely sets the URL that the reader represents.

Parameters:

file - the file for reading. This will most likely be directly related to the content URL.

url - the relative url that the reader represents

Method Detail

getSafeContentReader

public static org.alfresco.service.cmr.repository.ContentReader getSafeContentReader(org.alfresco.service.cmr.repository.ContentReader existingReader,
                                                                                     String msgTemplate,
                                                                                     Object... args)

Checks the existing reader provided and replaces it with a reader onto some fake content if required. If the existing reader is invalid, an debug message will be logged under this classname category.

It is a convenience method that clients can use to cheaply get a reader that is valid, regardless of whether the initial reader is valid.

Parameters:

existingReader - a potentially invalid reader or null

msgTemplate - the template message that will used to format the final fake content

args - arguments to put into the fake content

Returns:

Returns a the existing reader or a new reader onto some generated text content

getFile

public File getFile()

Specified by:

getFile in interface org.alfresco.service.cmr.repository.FileContentReader

Returns:

Returns the file that this reader accesses

exists

public boolean exists()

Specified by:

exists in interface org.alfresco.service.cmr.repository.ContentReader

Specified by:

exists in interface org.alfresco.service.cmr.repository.FileContentReader

Returns:

Whether the file exists or not

getSize

public long getSize()

Specified by:

getSize in interface org.alfresco.service.cmr.repository.ContentAccessor

See Also:

File.length()

getLastModified

public long getLastModified()

Specified by:

getLastModified in interface org.alfresco.service.cmr.repository.ContentReader

See Also:

File.lastModified()

createReader

protected org.alfresco.service.cmr.repository.ContentReader createReader()
                                                                  throws org.alfresco.service.cmr.repository.ContentIOException

The URL of the write is known from the start and this method contract states that no consideration needs to be taken w.r.t. the stream state.

Specified by:

createReader in class AbstractContentReader

Returns:

Returns a reader onto the location referenced by this instance. The instance must always be a new instance.

Throws:

org.alfresco.service.cmr.repository.ContentIOException

getDirectReadableChannel

protected ReadableByteChannel getDirectReadableChannel()
                                                throws org.alfresco.service.cmr.repository.ContentIOException

Description copied from class: AbstractContentReader

Provides low-level access to read content from the repository.

This is the only of the content reading methods that needs to be implemented by derived classes. All other content access methods make use of this in their underlying implementations.

Specified by:

getDirectReadableChannel in class AbstractContentReader

Returns:

Returns a channel from which content can be read

Throws:

org.alfresco.service.cmr.repository.ContentIOException - if the channel could not be opened or the underlying content has disappeared

canWrite

@Deprecated
public boolean canWrite()

Deprecated. Since 5.1. This method has no value: a file reader can never write (DH: 2015/02/17)

Returns:

Returns false as this is a reader