org.restlet.util
Class WrapperRepresentation

java.lang.Object
  org.restlet.resource.Variant
      org.restlet.resource.Representation
          org.restlet.util.WrapperRepresentation

Direct Known Subclasses:

DigestRepresentation

public class WrapperRepresentation
extends Representation

Representation wrapper. Useful for application developer who need to enrich the representation with application related properties and behavior.

Author:

Jerome Louvel

See Also:

The decorator (aka wrapper) pattern

Field Summary

Fields inherited from class org.restlet.resource.Representation

UNKNOWN_SIZE

Constructor Summary

WrapperRepresentation(Representation wrappedRepresentation)
Constructor.

Method Summary

boolean	checkDigest() Check that the digest computed from the representation content and the digest declared by the representation are the same. Since this method relies on the Representation.computeDigest(String) method, and since this method reads entirely the representation's stream, user must take care of the content of the representation in case the latter is transient.
boolean	checkDigest(String algorithm) Check that the digest computed from the representation content and the digest declared by the representation are the same.
Digest	computeDigest(String algorithm) Compute the representation digest according to the given algorithm. Since this method reads entirely the representation's stream, user must take care of the content of the representation in case the latter is transient.
long	exhaust() Exhauts the content of the representation by reading it and silently discarding anything read.
long	getAvailableSize() Returns the size effectively available.
ReadableByteChannel	getChannel() Returns a channel with the representation's content. If it is supported by a file, a read-only instance of FileChannel is returned. This method is ensured to return a fresh channel for each invocation unless it is a transient representation, in which case null is returned.
CharacterSet	getCharacterSet() Returns the character set or null if not applicable.
Digest	getDigest() Returns the representation digest if any.
String	getDownloadName() Returns the suggested download file name for this representation.
List<Encoding>	getEncodings() Returns the modifiable list of encodings applied to the entity-body.
Date	getExpirationDate() Returns the future date when this representation expire.
Reference	getIdentifier() Returns an optional identifier.
List<Language>	getLanguages() Returns the modifiable list of languages.
MediaType	getMediaType() Returns the media type.
Date	getModificationDate() Returns the last date when this representation was modified.
Range	getRange() Returns the range where in the full content the partial content available should be applied.
Reader	getReader() Returns a characters reader with the representation's content.
long	getSize() Returns the size in bytes if known, UNKNOWN_SIZE (-1) otherwise.
InputStream	getStream() Returns a stream with the representation's content.
Tag	getTag() Returns the tag.
String	getText() Converts the representation to a string value.
Representation	getWrappedRepresentation() Returns the wrapped representation.
boolean	isAvailable() Indicates if some fresh content is available, without having to actually call one of the content manipulation method like getStream() that would actually consume it.
boolean	isDownloadable() Indicates if the representation is downloadable which means that it can be obtained via a download dialog box.
boolean	isTransient() Indicates if the representation's content is transient, which means that it can be obtained only once.
void	release() Releases the representation's content and all associated objects like sockets, channels or files.
void	setAvailable(boolean isAvailable) Indicates if some fresh content is available.
void	setCharacterSet(CharacterSet characterSet) Sets the character set or null if not applicable.
void	setDigest(Digest digest) Sets the representation digest.
void	setDownloadable(boolean downloadable) Indicates if the representation is downloadable which means that it can be obtained via a download dialog box.
void	setDownloadName(String fileName) Set the suggested download file name for this representation.
void	setEncodings(List<Encoding> encodings) Sets the list of encodings applied to the entity-body.
void	setExpirationDate(Date expirationDate) Sets the future date when this representation expire.
void	setIdentifier(Reference identifier) Sets the optional identifier.
void	setIdentifier(String identifierUri) Sets the identifier from a URI string.
void	setLanguages(List<Language> languages) Sets the list of languages.
void	setMediaType(MediaType mediaType) Sets the media type.
void	setModificationDate(Date modificationDate) Sets the last date when this representation was modified.
void	setRange(Range range) Sets the range where in the full content the partial content available should be applied.
void	setSize(long expectedSize) Sets the expected size in bytes if known, -1 otherwise.
void	setTag(Tag tag) Sets the tag.
void	setTransient(boolean isTransient) Indicates if the representation's content is transient.
void	write(OutputStream outputStream) Writes the representation to a byte stream.
void	write(WritableByteChannel writableChannel) Writes the representation to a byte channel.
void	write(Writer writer) Writes the representation to a characters writer.

Methods inherited from class org.restlet.resource.Representation

createEmpty

Methods inherited from class java.lang.Object

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

Constructor Detail

WrapperRepresentation

public WrapperRepresentation(Representation wrappedRepresentation)

Constructor.

Parameters:

wrappedRepresentation - The wrapped representation.

Method Detail

checkDigest

public boolean checkDigest()

Description copied from class: Representation

Check that the digest computed from the representation content and the digest declared by the representation are the same.
Since this method relies on the Representation.computeDigest(String) method, and since this method reads entirely the representation's stream, user must take care of the content of the representation in case the latter is transient. Representation.isTransient

Overrides:

checkDigest in class Representation

Returns:

True if both digests are not null and equals.

checkDigest

public boolean checkDigest(String algorithm)

Description copied from class: Representation

Check that the digest computed from the representation content and the digest declared by the representation are the same. It also first checks that the algorithms are the same.
Since this method relies on the Representation.computeDigest(String) method, and since this method reads entirely the representation's stream, user must take care of the content of the representation in case the latter is transient. Representation.isTransient

Overrides:

checkDigest in class Representation

Parameters:

algorithm - The algorithm used to compute the digest to compare with. See constant values in Digest.

Returns:

True if both digests are not null and equals.

computeDigest

public Digest computeDigest(String algorithm)

Description copied from class: Representation

Compute the representation digest according to the given algorithm.
Since this method reads entirely the representation's stream, user must take care of the content of the representation in case the latter is transient. Representation.isTransient

Overrides:

computeDigest in class Representation

Parameters:

algorithm - The algorithm used to compute the digest. See constant values in Digest.

Returns:

The computed digest or null if the digest cannot be computed.

exhaust

public long exhaust()
             throws IOException

Description copied from class: Representation

Exhauts the content of the representation by reading it and silently discarding anything read.

Overrides:

exhaust in class Representation

Returns:

The number of bytes consumed or -1 if unknown.

Throws:

IOException

getAvailableSize

public long getAvailableSize()

Description copied from class: Representation

Returns the size effectively available. This returns the same value as Representation.getSize() if no range is defined, otherwise it returns the size of the range using Range.getSize().

Overrides:

getAvailableSize in class Representation

Returns:

The available size.

getChannel

public ReadableByteChannel getChannel()
                               throws IOException

Description copied from class: Representation

Returns a channel with the representation's content.
If it is supported by a file, a read-only instance of FileChannel is returned.
This method is ensured to return a fresh channel for each invocation unless it is a transient representation, in which case null is returned.

Specified by:

getChannel in class Representation

Returns:

A channel with the representation's content.

Throws:

IOException

getCharacterSet

public CharacterSet getCharacterSet()

Description copied from class: Variant

Returns the character set or null if not applicable.

Overrides:

getCharacterSet in class Variant

Returns:

The character set or null if not applicable.

getDigest

public Digest getDigest()

Description copied from class: Representation

Returns the representation digest if any.

Overrides:

getDigest in class Representation

Returns:

The representation digest or null.

getDownloadName

public String getDownloadName()

Description copied from class: Representation

Returns the suggested download file name for this representation. This is mainly used to suggest to the client a local name for a downloaded representation.

Overrides:

getDownloadName in class Representation

Returns:

The suggested file name for this representation.

getEncodings

public List<Encoding> getEncodings()

Description copied from class: Variant

Returns the modifiable list of encodings applied to the entity-body. Creates a new instance if no one has been set. An "IllegalArgumentException" exception is thrown when adding a null encoding to this list.

Overrides:

getEncodings in class Variant

Returns:

The list of encodings applied to the entity-body.

getExpirationDate

public Date getExpirationDate()

Description copied from class: Representation

Returns the future date when this representation expire. If this information is not known, returns null.

Overrides:

getExpirationDate in class Representation

Returns:

The expiration date.

getIdentifier

public Reference getIdentifier()

Description copied from class: Variant

Returns an optional identifier. This is useful when the representation is accessible from a location separate from the representation's resource URI, for example when content negotiation occurs.

Overrides:

getIdentifier in class Variant

Returns:

The identifier.

getLanguages

public List<Language> getLanguages()

Description copied from class: Variant

Returns the modifiable list of languages. Creates a new instance if no one has been set. An "IllegalArgumentException" exception is thrown when adding a null language to this list.

Overrides:

getLanguages in class Variant

Returns:

The list of languages.

getMediaType

public MediaType getMediaType()

Description copied from class: Variant

Returns the media type.

Overrides:

getMediaType in class Variant

Returns:

The media type.

getModificationDate

public Date getModificationDate()

Description copied from class: Representation

Returns the last date when this representation was modified. If this information is not known, returns null.

Overrides:

getModificationDate in class Representation

Returns:

The modification date.

getRange

public Range getRange()

Description copied from class: Representation

Returns the range where in the full content the partial content available should be applied.

Overrides:

getRange in class Representation

Returns:

The content range or null if the full content is available.

getReader

public Reader getReader()
                 throws IOException

Description copied from class: Representation

Returns a characters reader with the representation's content. This method is ensured to return a fresh reader for each invocation unless it is a transient representation, in which case null is returned. If the representation has no character set defined, the system's default one will be used.

Specified by:

getReader in class Representation

Returns:

A reader with the representation's content.

Throws:

IOException

getSize

public long getSize()

Description copied from class: Representation

Returns the size in bytes if known, UNKNOWN_SIZE (-1) otherwise.

Overrides:

getSize in class Representation

Returns:

The size in bytes if known, UNKNOWN_SIZE (-1) otherwise.

getStream

public InputStream getStream()
                      throws IOException

Description copied from class: Representation

Returns a stream with the representation's content. This method is ensured to return a fresh stream for each invocation unless it is a transient representation, in which case null is returned.

Specified by:

getStream in class Representation

Returns:

A stream with the representation's content.

Throws:

IOException

getTag

public Tag getTag()

Description copied from class: Representation

Returns the tag.

Overrides:

getTag in class Representation

Returns:

The tag.

getText

public String getText()
               throws IOException

Description copied from class: Representation

Converts the representation to a string value. Be careful when using this method as the conversion of large content to a string fully stored in memory can result in OutOfMemoryErrors being thrown.

Overrides:

getText in class Representation

Returns:

The representation as a string value.

Throws:

IOException

getWrappedRepresentation

public Representation getWrappedRepresentation()

Returns the wrapped representation.

Returns:

The wrapped representation.

isAvailable

public boolean isAvailable()

Description copied from class: Representation

Indicates if some fresh content is available, without having to actually call one of the content manipulation method like getStream() that would actually consume it. This is especially useful for transient representation whose content can only be accessed once and also when the size of the representation is not known in advance.

Overrides:

isAvailable in class Representation

Returns:

True if some fresh content is available.

isDownloadable

public boolean isDownloadable()

Description copied from class: Representation

Indicates if the representation is downloadable which means that it can be obtained via a download dialog box.

Overrides:

isDownloadable in class Representation

Returns:

True if the representation's content is downloadable.

isTransient

public boolean isTransient()

Description copied from class: Representation

Indicates if the representation's content is transient, which means that it can be obtained only once. This is often the case with representations transmitted via network sockets for example. In such case, if you need to read the content several times, you need to cache it first, for example into memory or into a file.

Overrides:

isTransient in class Representation

Returns:

True if the representation's content is transient.

release

public void release()

Description copied from class: Representation

Releases the representation's content and all associated objects like sockets, channels or files. If the representation is transient and hasn't been read yet, all the remaining content will be discarded, any open socket, channel, file or similar source of content will be immediately closed. The representation is also no more available.

Overrides:

release in class Representation

setAvailable

public void setAvailable(boolean isAvailable)

Description copied from class: Representation

Indicates if some fresh content is available.

Overrides:

setAvailable in class Representation

Parameters:

isAvailable - True if some fresh content is available.

setCharacterSet

public void setCharacterSet(CharacterSet characterSet)

Description copied from class: Variant

Sets the character set or null if not applicable.

Overrides:

setCharacterSet in class Variant

Parameters:

characterSet - The character set or null if not applicable.

setDigest

public void setDigest(Digest digest)

Description copied from class: Representation

Sets the representation digest.

Overrides:

setDigest in class Representation

Parameters:

digest - The representation digest.

setDownloadable

public void setDownloadable(boolean downloadable)

Description copied from class: Representation

Indicates if the representation is downloadable which means that it can be obtained via a download dialog box.

Overrides:

setDownloadable in class Representation

Parameters:

downloadable - True if the representation's content is downloadable.

setDownloadName

public void setDownloadName(String fileName)

Description copied from class: Representation

Set the suggested download file name for this representation.

Overrides:

setDownloadName in class Representation

Parameters:

fileName - The suggested file name.

setEncodings

public void setEncodings(List<Encoding> encodings)

Description copied from class: Variant

Sets the list of encodings applied to the entity-body.

Overrides:

setEncodings in class Variant

Parameters:

encodings - The list of encodings applied to the entity-body.

setExpirationDate

public void setExpirationDate(Date expirationDate)

Description copied from class: Representation

Sets the future date when this representation expire. If this information is not known, pass null.

Overrides:

setExpirationDate in class Representation

Parameters:

expirationDate - The expiration date.

setIdentifier

public void setIdentifier(Reference identifier)

Description copied from class: Variant

Sets the optional identifier. This is useful when the representation is accessible from a location separate from the representation's resource URI, for example when content negotiation occurs.

Overrides:

setIdentifier in class Variant

Parameters:

identifier - The identifier.

setIdentifier

public void setIdentifier(String identifierUri)

Description copied from class: Variant

Sets the identifier from a URI string.

Overrides:

setIdentifier in class Variant

Parameters:

identifierUri - The identifier to parse.

setLanguages

public void setLanguages(List<Language> languages)

Description copied from class: Variant

Sets the list of languages.

Overrides:

setLanguages in class Variant

Parameters:

languages - The list of languages.

setMediaType

public void setMediaType(MediaType mediaType)

Description copied from class: Variant

Sets the media type.

Overrides:

setMediaType in class Variant

Parameters:

mediaType - The media type.

setModificationDate

public void setModificationDate(Date modificationDate)

Description copied from class: Representation

Sets the last date when this representation was modified. If this information is not known, pass null.

Overrides:

setModificationDate in class Representation

Parameters:

modificationDate - The modification date.

setRange

public void setRange(Range range)

Description copied from class: Representation

Sets the range where in the full content the partial content available should be applied.

Overrides:

setRange in class Representation

Parameters:

range - The content range.

setSize

public void setSize(long expectedSize)

Description copied from class: Representation

Sets the expected size in bytes if known, -1 otherwise.

Overrides:

setSize in class Representation

Parameters:

expectedSize - The expected size in bytes if known, -1 otherwise.

setTag

public void setTag(Tag tag)

Description copied from class: Representation

Sets the tag.

Overrides:

setTag in class Representation

Parameters:

tag - The tag.

setTransient

public void setTransient(boolean isTransient)

Description copied from class: Representation

Indicates if the representation's content is transient.

Overrides:

setTransient in class Representation

Parameters:

isTransient - True if the representation's content is transient.

write

public void write(OutputStream outputStream)
           throws IOException

Description copied from class: Representation

Writes the representation to a byte stream. This method is ensured to write the full content for each invocation unless it is a transient representation, in which case an exception is thrown.

Specified by:

write in class Representation

Parameters:

outputStream - The output stream.

Throws:

IOException

write

public void write(WritableByteChannel writableChannel)
           throws IOException

Description copied from class: Representation

Writes the representation to a byte channel. This method is ensured to write the full content for each invocation unless it is a transient representation, in which case an exception is thrown.

Specified by:

write in class Representation

Parameters:

writableChannel - A writable byte channel.

Throws:

IOException

write

public void write(Writer writer)
           throws IOException

Description copied from class: Representation

Writes the representation to a characters writer. This method is ensured to write the full content for each invocation unless it is a transient representation, in which case an exception is thrown.

Specified by:

write in class Representation

Parameters:

writer - The characters writer.

Throws:

IOException