public abstract class IIOMetadata extends Object
IIOMetadataNode objects that support the XML DOM interfaces as well as additional interfaces for storing non-textual data and retrieving information about legal data values. The format of such trees is plug-in dependent, but plug-ins may choose to support a plug-in neutral format described below. A single plug-in may support multiple metadata formats, whose names maybe determined by calling
getMetadataFormatNames. The plug-in may also support a single special format, referred to as the "native" format, which is designed to encode its metadata losslessly. This format will typically be designed specifically to work with a specific file format, so that images may be loaded and saved in the same format with no loss of metadata, but may be less useful for transferring metadata between an
ImageReader and an
ImageWriter for different image formats. To convert between two native formats as losslessly as the image file formats will allow, an
ImageTranscoder object must be used.
ImageReader.getImageMetadata(int) ,
ImageReader.getStreamMetadata() ,
ImageReader.readAll(int, javax.imageio.ImageReadParam) ,
ImageWriter.getDefaultStreamMetadata(javax.imageio.ImageWriteParam) ,
ImageWriter.getDefaultImageMetadata(javax.imageio.ImageTypeSpecifier, javax.imageio.ImageWriteParam) ,
ImageWriter.write(javax.imageio.metadata.IIOMetadata, javax.imageio.IIOImage, javax.imageio.ImageWriteParam) ,
ImageWriter.convertImageMetadata(javax.imageio.metadata.IIOMetadata, javax.imageio.ImageTypeSpecifier, javax.imageio.ImageWriteParam) ,
ImageWriter.convertStreamMetadata(javax.imageio.metadata.IIOMetadata, javax.imageio.ImageWriteParam) ,
IIOImage,
ImageTranscoder
| Modifier and Type | Field and Description |
|---|---|
protected IIOMetadataController |
controller
The
IIOMetadataController that will be used to provide settings for this
IIOMetadata object when the
activateController method is called.
|
protected IIOMetadataController |
defaultController
An
IIOMetadataController that is suggested for use as the controller for this
IIOMetadata object.
|
protected String |
extraMetadataFormatClassNames
An array of names of classes implementing
IIOMetadataFormat and representing the metadata formats, other than the standard and native formats, that are supported by this plug-in, initialized to
null and set via the constructor.
|
protected String |
extraMetadataFormatNames
An array of names of formats, other than the standard and native formats, that are supported by this plug-in, initialized to
null and set via the constructor.
|
protected String |
nativeMetadataFormatClassName
The name of the class implementing
IIOMetadataFormat and representing the native metadata format, initialized to
null and set via the constructor.
|
protected String |
nativeMetadataFormatName
The name of the native metadata format for this object, initialized to
null and set via the constructor.
|
protected boolean |
standardFormatSupported
A boolean indicating whether the concrete subclass supports the standard metadata format, set via the constructor.
|
| Modifier | Constructor and Description |
|---|---|
protected |
IIOMetadata()
Constructs an empty
IIOMetadata object.
|
protected |
IIOMetadata(boolean standardMetadataFormatSupported, String
Constructs an
IIOMetadata object with the given format names and format class names, as well as a boolean indicating whether the standard format is supported.
|
| Modifier and Type | Method and Description |
|---|---|
boolean |
activateController()
Activates the installed
IIOMetadataController for this
IIOMetadata object and returns the resulting value.
|
abstract Node |
getAsTree(String
Returns an XML DOM
Node object that represents the root of a tree of metadata contained within this object according to the conventions defined by a given metadata format.
|
IIOMetadataController |
getController()
Returns whatever
IIOMetadataController is currently installed.
|
IIOMetadataController |
getDefaultController()
Returns the default
IIOMetadataController, if there is one, regardless of the currently installed controller.
|
String |
getExtraMetadataFormatNames()
Returns an array of
Strings containing the names of additional metadata formats, other than the native and standard formats, recognized by this plug-in's
getAsTree,
setFromTree, and
mergeTree methods.
|
IIOMetadataFormat |
getMetadataFormat(String
Returns an
IIOMetadataFormat object describing the given metadata format, or
null if no description is available.
|
String |
getMetadataFormatNames()
Returns an array of
Strings containing the names of all metadata formats, including the native and standard formats, recognized by this plug-in's
getAsTree,
setFromTree, and
mergeTree methods.
|
String |
getNativeMetadataFormatName()
Returns the name of the "native" metadata format for this plug-in, which typically allows for lossless encoding and transmission of the metadata stored in the format handled by this plug-in.
|
protected IIOMetadataNode |
getStandardChromaNode()
Returns an
IIOMetadataNode representing the chroma information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available.
|
protected IIOMetadataNode |
getStandardCompressionNode()
Returns an
IIOMetadataNode representing the compression information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available.
|
protected IIOMetadataNode |
getStandardDataNode()
Returns an
IIOMetadataNode representing the data format information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available.
|
protected IIOMetadataNode |
getStandardDimensionNode()
Returns an
IIOMetadataNode representing the dimension information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available.
|
protected IIOMetadataNode |
getStandardDocumentNode()
Returns an
IIOMetadataNode representing the document information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available.
|
protected IIOMetadataNode |
getStandardTextNode()
Returns an
IIOMetadataNode representing the textual information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available.
|
protected IIOMetadataNode |
getStandardTileNode()
Returns an
IIOMetadataNode representing the tiling information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available.
|
protected IIOMetadataNode |
getStandardTransparencyNode()
Returns an
IIOMetadataNode representing the transparency information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available.
|
protected IIOMetadataNode |
getStandardTree()
A utility method to return a tree of
IIOMetadataNodes representing the metadata contained within this object according to the conventions of the standard
javax_imageio_1.0 metadata format.
|
boolean |
hasController()
Returns
true if there is a controller installed for this
IIOMetadata object.
|
abstract boolean |
isReadOnly()
Returns
true if this object does not support the
mergeTree,
setFromTree, and
reset methods.
|
boolean |
isStandardMetadataFormatSupported()
Returns
true if the standard metadata format is supported by
getMetadataFormat,
getAsTree,
setFromTree, and
mergeTree.
|
abstract void |
mergeTree(String
Alters the internal state of this
IIOMetadata object from a tree of XML DOM
Nodes whose syntax is defined by the given metadata format.
|
abstract void |
reset()
Resets all the data stored in this object to default values, usually to the state this object was in immediately after construction, though the precise semantics are plug-in specific.
|
void |
setController(IIOMetadataController
Sets the
IIOMetadataController to be used to provide settings for this
IIOMetadata object when the
activateController method is called, overriding any default controller.
|
void |
setFromTree(String
Sets the internal state of this
IIOMetadata object from a tree of XML DOM
Nodes whose syntax is defined by the given metadata format.
|
protected boolean standardFormatSupported
protected StringnativeMetadataFormatName
null and set via the constructor.
protected StringnativeMetadataFormatClassName
IIOMetadataFormat and representing the native metadata format, initialized to
null and set via the constructor.
protected String[] extraMetadataFormatNames
null and set via the constructor.
protected String[] extraMetadataFormatClassNames
IIOMetadataFormat and representing the metadata formats, other than the standard and native formats, that are supported by this plug-in, initialized to
null and set via the constructor.
protected IIOMetadataControllerdefaultController
IIOMetadataController that is suggested for use as the controller for this
IIOMetadata object. It may be retrieved via
getDefaultController. To install the default controller, call
setController(getDefaultController()). This instance variable should be set by subclasses that choose to provide their own default controller, usually a GUI, for setting parameters.
IIOMetadataController,
getDefaultController()
protected IIOMetadataControllercontroller
IIOMetadataController that will be used to provide settings for this
IIOMetadata object when the
activateController method is called. This value overrides any default controller, even when
null.
protected IIOMetadata()
IIOMetadata object. The subclass is responsible for supplying values for all protected instance variables that will allow any non-overridden default implementations of methods to satisfy their contracts. For example,
extraMetadataFormatNames should not have length 0.
protected IIOMetadata(boolean standardMetadataFormatSupported,
String nativeMetadataFormatName,
String nativeMetadataFormatClassName,
String[] extraMetadataFormatNames,
String[] extraMetadataFormatClassNames)
IIOMetadata object with the given format names and format class names, as well as a boolean indicating whether the standard format is supported.
This constructor does not attempt to check the class names for validity. Invalid class names may cause exceptions in subsequent calls to getMetadataFormat.
standardMetadataFormatSupported -
true if this object can return or accept a DOM tree using the standard metadata format.
nativeMetadataFormatName - the name of the native metadata format, as a
String, or
null if there is no native format.
nativeMetadataFormatClassName - the name of the class of the native metadata format, or
null if there is no native format.
extraMetadataFormatNames - an array of
Strings indicating additional formats supported by this object, or
null if there are none.
extraMetadataFormatClassNames - an array of
Strings indicating the class names of any additional formats supported by this object, or
null if there are none.
IllegalArgumentException - if
extraMetadataFormatNames has length 0.
IllegalArgumentException - if
extraMetadataFormatNames and
extraMetadataFormatClassNames are neither both
null, nor of the same length.
public boolean isStandardMetadataFormatSupported()
true if the standard metadata format is supported by
getMetadataFormat,
getAsTree,
setFromTree, and
mergeTree.
The default implementation returns the value of the standardFormatSupported instance variable.
true if the standard metadata format is supported.
getAsTree(java.lang.String),
setFromTree(java.lang.String, org.w3c.dom.Node),
mergeTree(java.lang.String, org.w3c.dom.Node),
getMetadataFormat(java.lang.String)
public abstract boolean isReadOnly()
true if this object does not support the
mergeTree,
setFromTree, and
reset methods.
IIOMetadata object cannot be modified.
public StringgetNativeMetadataFormatName()
nullwill be returned.
The structure and contents of the "native" metadata format are defined by the plug-in that created this IIOMetadata object. Plug-ins for simple formats will usually create a dummy node for the root, and then a series of child nodes representing individual tags, chunks, or keyword/value pairs. A plug-in may choose whether or not to document its native format.
The default implementation returns the value of the nativeMetadataFormatName instance variable.
null.
getExtraMetadataFormatNames(),
getMetadataFormatNames()
public String[] getExtraMetadataFormatNames()
Strings containing the names of additional metadata formats, other than the native and standard formats, recognized by this plug-in's
getAsTree,
setFromTree, and
mergeTree methods. If there are no such additional formats,
null is returned.
The default implementation returns a clone of the extraMetadataFormatNames instance variable.
Strings with length at least 1, or
null.
getAsTree(java.lang.String),
setFromTree(java.lang.String, org.w3c.dom.Node),
mergeTree(java.lang.String, org.w3c.dom.Node),
getNativeMetadataFormatName(),
getMetadataFormatNames()
public String[] getMetadataFormatNames()
Strings containing the names of all metadata formats, including the native and standard formats, recognized by this plug-in's
getAsTree,
setFromTree, and
mergeTree methods. If there are no such formats,
null is returned.
The default implementation calls getNativeMetadataFormatName, isStandardMetadataFormatSupported, and getExtraMetadataFormatNames and returns the combined results.
Strings.
getNativeMetadataFormatName(),
isStandardMetadataFormatSupported(),
getExtraMetadataFormatNames()
public IIOMetadataFormatgetMetadataFormat(String formatName)
IIOMetadataFormat object describing the given metadata format, or
null if no description is available. The supplied name must be one of those returned by
getMetadataFormatNames (
i.e., either the native format name, the standard format name, or one of those returned by
getExtraMetadataFormatNames).
The default implementation checks the name against the global standard metadata format name, and returns that format if it is supported. Otherwise, it checks against the native format names followed by any additional format names. If a match is found, it retrieves the name of the IIOMetadataFormat class from nativeMetadataFormatClassName or extraMetadataFormatClassNames as appropriate, and constructs an instance of that class using its getInstance method.
formatName - the desired metadata format.
IIOMetadataFormat object.
IllegalArgumentException - if
formatName is
null or is not one of the names recognized by the plug-in.
IllegalStateException - if the class corresponding to the format name cannot be loaded.
public abstract NodegetAsTree(String formatName)
Node object that represents the root of a tree of metadata contained within this object according to the conventions defined by a given metadata format.
The names of the available metadata formats may be queried using the getMetadataFormatNames method.
formatName - the desired metadata format.
Node object forming the root of a tree.
IllegalArgumentException - if
formatName is
null or is not one of the names returned by
getMetadataFormatNames.
getMetadataFormatNames(),
setFromTree(java.lang.String, org.w3c.dom.Node),
mergeTree(java.lang.String, org.w3c.dom.Node)
public abstract void mergeTree(StringformatName, Node root) throws IIOInvalidTreeException
IIOMetadata object from a tree of XML DOM
Nodes whose syntax is defined by the given metadata format. The previous state is altered only as necessary to accommodate the nodes that are present in the given tree. If the tree structure or contents are invalid, an
IIOInvalidTreeException will be thrown.
As the semantics of how a tree or subtree may be merged with another tree are completely format-specific, plug-in authors may implement this method in whatever manner is most appropriate for the format, including simply replacing all existing state with the contents of the given tree.
formatName - the desired metadata format.
root - an XML DOM
Node object forming the root of a tree.
IllegalStateException - if this object is read-only.
IllegalArgumentException - if
formatName is
null or is not one of the names returned by
getMetadataFormatNames.
IllegalArgumentException - if
root is
null.
IIOInvalidTreeException - if the tree cannot be parsed successfully using the rules of the given format.
getMetadataFormatNames(),
getAsTree(java.lang.String),
setFromTree(java.lang.String, org.w3c.dom.Node)
protected IIOMetadataNodegetStandardChromaNode()
IIOMetadataNode representing the chroma information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available. This method is intended to be called by the utility routine
getStandardTree.
The default implementation returns null.
Subclasses should override this method to produce an appropriate subtree if they wish to support the standard metadata format.
IIOMetadataNode, or
null.
getStandardTree()
protected IIOMetadataNodegetStandardCompressionNode()
IIOMetadataNode representing the compression information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available. This method is intended to be called by the utility routine
getStandardTree.
The default implementation returns null.
Subclasses should override this method to produce an appropriate subtree if they wish to support the standard metadata format.
IIOMetadataNode, or
null.
getStandardTree()
protected IIOMetadataNodegetStandardDataNode()
IIOMetadataNode representing the data format information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available. This method is intended to be called by the utility routine
getStandardTree.
The default implementation returns null.
Subclasses should override this method to produce an appropriate subtree if they wish to support the standard metadata format.
IIOMetadataNode, or
null.
getStandardTree()
protected IIOMetadataNodegetStandardDimensionNode()
IIOMetadataNode representing the dimension information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available. This method is intended to be called by the utility routine
getStandardTree.
The default implementation returns null.
Subclasses should override this method to produce an appropriate subtree if they wish to support the standard metadata format.
IIOMetadataNode, or
null.
getStandardTree()
protected IIOMetadataNodegetStandardDocumentNode()
IIOMetadataNode representing the document information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available. This method is intended to be called by the utility routine
getStandardTree.
The default implementation returns null.
Subclasses should override this method to produce an appropriate subtree if they wish to support the standard metadata format.
IIOMetadataNode, or
null.
getStandardTree()
protected IIOMetadataNodegetStandardTextNode()
IIOMetadataNode representing the textual information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available. This method is intended to be called by the utility routine
getStandardTree.
The default implementation returns null.
Subclasses should override this method to produce an appropriate subtree if they wish to support the standard metadata format.
IIOMetadataNode, or
null.
getStandardTree()
protected IIOMetadataNodegetStandardTileNode()
IIOMetadataNode representing the tiling information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available. This method is intended to be called by the utility routine
getStandardTree.
The default implementation returns null.
Subclasses should override this method to produce an appropriate subtree if they wish to support the standard metadata format.
IIOMetadataNode, or
null.
getStandardTree()
protected IIOMetadataNodegetStandardTransparencyNode()
IIOMetadataNode representing the transparency information of the standard
javax_imageio_1.0 metadata format, or
null if no such information is available. This method is intended to be called by the utility routine
getStandardTree.
The default implementation returns null.
Subclasses should override this method to produce an appropriate subtree if they wish to support the standard metadata format.
IIOMetadataNode, or
null.
protected final IIOMetadataNodegetStandardTree()
IIOMetadataNodes representing the metadata contained within this object according to the conventions of the standard
javax_imageio_1.0 metadata format.
This method calls the various getStandard*Node methods to supply each of the subtrees rooted at the children of the root node. If any of those methods returns null, the corresponding subtree will be omitted. If all of them return null, a tree consisting of a single root node will be returned.
IIOMetadataNode representing the root of a metadata tree in the
javax_imageio_1.0 format.
getStandardChromaNode(),
getStandardCompressionNode(),
getStandardDataNode(),
getStandardDimensionNode(),
getStandardDocumentNode(),
getStandardTextNode(),
getStandardTileNode(),
getStandardTransparencyNode()
public void setFromTree(StringformatName, Node root) throws IIOInvalidTreeException
IIOMetadata object from a tree of XML DOM
Nodes whose syntax is defined by the given metadata format. The previous state is discarded. If the tree's structure or contents are invalid, an
IIOInvalidTreeException will be thrown.
The default implementation calls reset followed by mergeTree(formatName, root).
formatName - the desired metadata format.
root - an XML DOM
Node object forming the root of a tree.
IllegalStateException - if this object is read-only.
IllegalArgumentException - if
formatName is
null or is not one of the names returned by
getMetadataFormatNames.
IllegalArgumentException - if
root is
null.
IIOInvalidTreeException - if the tree cannot be parsed successfully using the rules of the given format.
getMetadataFormatNames(),
getAsTree(java.lang.String),
mergeTree(java.lang.String, org.w3c.dom.Node)
public abstract void reset()
IllegalStateException - if this object is read-only.
ImageReader.getStreamMetadata() ,
ImageReader.getImageMetadata(int) ,
ImageWriter.getDefaultStreamMetadata(javax.imageio.ImageWriteParam) ,
ImageWriter.getDefaultImageMetadata(javax.imageio.ImageTypeSpecifier, javax.imageio.ImageWriteParam)
public void setController(IIOMetadataControllercontroller)
IIOMetadataController to be used to provide settings for this
IIOMetadata object when the
activateController method is called, overriding any default controller. If the argument is
null, no controller will be used, including any default. To restore the default, use
setController(getDefaultController()).
The default implementation sets the controller instance variable to the supplied value.
controller - An appropriate
IIOMetadataController, or
null.
IIOMetadataController,
getController(),
getDefaultController(),
hasController(),
activateController()
public IIOMetadataControllergetController()
IIOMetadataController is currently installed. This could be the default if there is one,
null, or the argument of the most recent call to
setController.
The default implementation returns the value of the controller instance variable.
IIOMetadataController, or
null.
IIOMetadataController,
setController(javax.imageio.metadata.IIOMetadataController),
getDefaultController(),
hasController(),
activateController()
public IIOMetadataControllergetDefaultController()
IIOMetadataController, if there is one, regardless of the currently installed controller. If there is no default controller, returns
null.
The default implementation returns the value of the defaultController instance variable.
IIOMetadataController, or
null.
IIOMetadataController,
setController(IIOMetadataController),
getController(),
hasController(),
activateController()
public boolean hasController()
true if there is a controller installed for this
IIOMetadata object.
The default implementation returns true if the getController method returns a non-null value.
true if a controller is installed.
IIOMetadataController,
setController(IIOMetadataController),
getController(),
getDefaultController(),
activateController()
public boolean activateController()
IIOMetadataController for this
IIOMetadata object and returns the resulting value. When this method returns
true, all values for this
IIOMetadata object will be ready for the next write operation. If
false is returned, no settings in this object will have been disturbed (
i.e., the user canceled the operation).
Ordinarily, the controller will be a GUI providing a user interface for a subclass of IIOMetadata for a particular plug-in. Controllers need not be GUIs, however.
The default implementation calls getController and the calls activate on the returned object if hasController returns true.
true if the controller completed normally.
IllegalStateException - if there is no controller currently installed.
IIOMetadataController,
setController(IIOMetadataController),
getController(),
getDefaultController(),
hasController()