javax.imageio.metadata

Class IIOMetadataFormatImpl

java.lang.Object

javax.imageio.metadata.IIOMetadataFormatImpl

All Implemented Interfaces:

IIOMetadataFormat

public abstract class IIOMetadataFormatImpl
extends Object
implements IIOMetadataFormat

A concrete class providing a reusable implementation of the IIOMetadataFormat interface. In addition, a static instance representing the standard, plug-in neutral javax_imageio_1.0 format is provided by the getStandardFormatInstance method.

In order to supply localized descriptions of elements and attributes, a ResourceBundle with a base name of this.getClass().getName() + "Resources" should be supplied via the usual mechanism used by ResourceBundle.getBundle. Briefly, the subclasser supplies one or more additional classes according to a naming convention (by default, the fully-qualified name of the subclass extending IIMetadataFormatImpl, plus the string "Resources", plus the country, language, and variant codes separated by underscores). At run time, calls to getElementDescription or getAttributeDescription will attempt to load such classes dynamically according to the supplied locale, and will use either the element name, or the element name followed by a '/' character followed by the attribute name as a key. This key will be supplied to the ResourceBundle's getString method, and the resulting localized description of the node or attribute is returned.

The subclass may supply a different base name for the resource bundles using the setResourceBaseName method.

A subclass may choose its own localization mechanism, if so desired, by overriding the supplied implementations of getElementDescription and getAttributeDescription.

See Also:

ResourceBundle.getBundle(String,Locale)

Field Summary

Fields

Modifier and Type	Field and Description
static String	standardMetadataFormatName A String constant containing the standard format name, "javax_imageio_1.0".

Fields inherited from interface javax.imageio.metadata.IIOMetadataFormat

CHILD_POLICY_ALL, CHILD_POLICY_CHOICE, CHILD_POLICY_EMPTY, CHILD_POLICY_MAX, CHILD_POLICY_REPEAT, CHILD_POLICY_SEQUENCE, CHILD_POLICY_SOME, DATATYPE_BOOLEAN, DATATYPE_DOUBLE, DATATYPE_FLOAT, DATATYPE_INTEGER, DATATYPE_STRING, VALUE_ARBITRARY, VALUE_ENUMERATION, VALUE_LIST, VALUE_NONE, VALUE_RANGE, VALUE_RANGE_MAX_INCLUSIVE, VALUE_RANGE_MAX_INCLUSIVE_MASK, VALUE_RANGE_MIN_INCLUSIVE, VALUE_RANGE_MIN_INCLUSIVE_MASK, VALUE_RANGE_MIN_MAX_INCLUSIVE

Constructor Summary

Constructors

Constructor and Description
IIOMetadataFormatImpl(String rootName, int childPolicy) Constructs a blank IIOMetadataFormatImpl instance, with a given root element name and child policy (other than CHILD_POLICY_REPEAT).
IIOMetadataFormatImpl(String rootName, int minChildren, int maxChildren) Constructs a blank IIOMetadataFormatImpl instance, with a given root element name and a child policy of CHILD_POLICY_REPEAT.

Method Summary

Methods

Modifier and Type	Method and Description
protected void	addAttribute(String elementName, String attrName, int dataType, boolean required, int listMinLength, int listMaxLength) Adds a new attribute to a previously defined element that will be defined by a list of values.
protected void	addAttribute(String elementName, String attrName, int dataType, boolean required, String defaultValue) Adds a new attribute to a previously defined element that may be set to an arbitrary value.
protected void	addAttribute(String elementName, String attrName, int dataType, boolean required, String defaultValue, List<String> enumeratedValues) Adds a new attribute to a previously defined element that will be defined by a set of enumerated values.
protected void	addAttribute(String elementName, String attrName, int dataType, boolean required, String defaultValue, String minValue, String maxValue, boolean minInclusive, boolean maxInclusive) Adds a new attribute to a previously defined element that will be defined by a range of values.
protected void	addBooleanAttribute(String elementName, String attrName, boolean hasDefaultValue, boolean defaultValue) Adds a new attribute to a previously defined element that will be defined by the enumerated values TRUE and FALSE, with a datatype of DATATYPE_BOOLEAN.
protected void	addChildElement(String elementName, String parentName) Adds an existing element to the list of legal children for a given parent node type.
protected void	addElement(String elementName, String parentName, int childPolicy) Adds a new element type to this metadata document format with a child policy other than CHILD_POLICY_REPEAT.
protected void	addElement(String elementName, String parentName, int minChildren, int maxChildren) Adds a new element type to this metadata document format with a child policy of CHILD_POLICY_REPEAT.
protected void	addObjectValue(String elementName, Class<?> classType, int arrayMinLength, int arrayMaxLength) Allows an Object reference of a given class type to be stored in nodes implementing the named element.
protected <T> void	addObjectValue(String elementName, Class<T> classType, boolean required, T defaultValue) Allows an Object reference of a given class type to be stored in nodes implementing the named element.
protected <T> void	addObjectValue(String elementName, Class<T> classType, boolean required, T defaultValue, List<? extends T> enumeratedValues) Allows an Object reference of a given class type to be stored in nodes implementing the named element.
protected <T extends Object & Comparable<? super T>> void	addObjectValue(String elementName, Class<T> classType, T defaultValue, Comparable<? super T> minValue, Comparable<? super T> maxValue, boolean minInclusive, boolean maxInclusive) Allows an Object reference of a given class type to be stored in nodes implementing the named element.
abstract boolean	canNodeAppear(String elementName, ImageTypeSpecifier imageType) Returns true if the element (and the subtree below it) is allowed to appear in a metadata document for an image of the given type, defined by an ImageTypeSpecifier.
int	getAttributeDataType(String elementName, String attrName) Returns one of the constants starting with DATATYPE_, indicating the format and interpretation of the value of the given attribute within th enamed element.
String	getAttributeDefaultValue(String elementName, String attrName) Returns the default value of the named attribute, if it is not explictly present within the named element, as a String, or null if no default value is available.
String	getAttributeDescription(String elementName, String attrName, Locale locale) Returns a String containing a description of the named attribute, or null.
String[]	getAttributeEnumerations(String elementName, String attrName) Returns an array of Strings containing the legal enumerated values for the given attribute within the named element.
int	getAttributeListMaxLength(String elementName, String attrName) Returns the maximum number of list items that may be used to define this attribute.
int	getAttributeListMinLength(String elementName, String attrName) Returns the minimum number of list items that may be used to define this attribute.
String	getAttributeMaxValue(String elementName, String attrName) Returns the maximum legal value for the attribute.
String	getAttributeMinValue(String elementName, String attrName) Returns the minimum legal value for the attribute.
String[]	getAttributeNames(String elementName) Returns an array of Strings listing the names of the attributes that may be associated with the named element.
int	getAttributeValueType(String elementName, String attrName) Returns one of the constants starting with VALUE_, indicating whether the values of the given attribute within the named element are arbitrary, constrained to lie within a specified range, constrained to be one of a set of enumerated values, or are a whitespace-separated list of arbitrary values.
String[]	getChildNames(String elementName) Returns an array of Strings indicating the names of the element which are allowed to be children of the named element, in the order in which they should appear.
int	getChildPolicy(String elementName) Returns one of the constants starting with CHILD_POLICY_, indicating the legal pattern of children for the named element.
String	getElementDescription(String elementName, Locale locale) Returns a String containing a description of the named element, or null.
int	getElementMaxChildren(String elementName) Returns the maximum number of children of the named element with child policy CHILD_POLICY_REPEAT.
int	getElementMinChildren(String elementName) Returns the minimum number of children of the named element with child policy CHILD_POLICY_REPEAT.
int	getObjectArrayMaxLength(String elementName) Returns the maximum number of array elements that may be used to define the Object reference within the named element.
int	getObjectArrayMinLength(String elementName) Returns the minimum number of array elements that may be used to define the Object reference within the named element.
Class<?>	getObjectClass(String elementName) Returns the Class type of the Object reference stored within the element.
Object	getObjectDefaultValue(String elementName) Returns an Objects containing the default value for the Object reference within the named element.
Object[]	getObjectEnumerations(String elementName) Returns an array of Objects containing the legal enumerated values for the Object reference within the named element.
Comparable<?>	getObjectMaxValue(String elementName) Returns the maximum legal value for the Object reference within the named element.
Comparable<?>	getObjectMinValue(String elementName) Returns the minimum legal value for the Object reference within the named element.
int	getObjectValueType(String elementName) Returns one of the enumerated values starting with VALUE_, indicating the type of values (enumeration, range, or array) that are allowed for the Object reference.
protected String	getResourceBaseName() Returns the currently set base name for locating ResourceBundles.
String	getRootName() Returns the name of the root element of the format.
static IIOMetadataFormat	getStandardFormatInstance() Returns an IIOMetadataFormat object describing the standard, plug-in neutral javax.imageio_1.0 metadata document format described in the comment of the javax.imageio.metadata package.
boolean	isAttributeRequired(String elementName, String attrName) Returns true if the named attribute must be present within the named element.
protected void	removeAttribute(String elementName, String attrName) Removes an attribute from a previously defined element.
protected void	removeElement(String elementName) Removes an element from the format.
protected void	removeObjectValue(String elementName) Disallows an Object reference from being stored in nodes implementing the named element.
protected void	setResourceBaseName(String resourceBaseName) Sets a new base name for locating ResourceBundles containing descriptions of elements and attributes for this format.

Methods inherited from class java.lang.Object

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

Field Detail

standardMetadataFormatName

public static final String standardMetadataFormatName

A String constant containing the standard format name, "javax_imageio_1.0".

See Also:

Constant Field Values

Constructor Detail

IIOMetadataFormatImpl

public IIOMetadataFormatImpl(String rootName,
                     int childPolicy)

Constructs a blank IIOMetadataFormatImpl instance, with a given root element name and child policy (other than CHILD_POLICY_REPEAT). Additional elements, and their attributes and Object reference information may be added using the various add methods.

Parameters:

rootName - the name of the root element.

childPolicy - one of the CHILD_POLICY_* constants, other than CHILD_POLICY_REPEAT.

Throws:

IllegalArgumentException - if rootName is null.

IllegalArgumentException - if childPolicy is not one of the predefined constants.

IIOMetadataFormatImpl

public IIOMetadataFormatImpl(String rootName,
                     int minChildren,
                     int maxChildren)

Constructs a blank IIOMetadataFormatImpl instance, with a given root element name and a child policy of CHILD_POLICY_REPEAT. Additional elements, and their attributes and Object reference information may be added using the various add methods.

Parameters:

rootName - the name of the root element.

minChildren - the minimum number of children of the node.

maxChildren - the maximum number of children of the node.

Throws:

IllegalArgumentException - if rootName is null.

IllegalArgumentException - if minChildren is negative or larger than maxChildren.

Method Detail

setResourceBaseName

protected void setResourceBaseName(String resourceBaseName)

Sets a new base name for locating ResourceBundles containing descriptions of elements and attributes for this format.

Prior to the first time this method is called, the base name will be equal to this.getClass().getName() + "Resources".

Parameters:

resourceBaseName - a String containg the new base name.

Throws:

IllegalArgumentException - if resourceBaseName is null.

See Also:

getResourceBaseName()

getResourceBaseName

protected String getResourceBaseName()

Returns the currently set base name for locating ResourceBundles.

Returns:

a String containing the base name.

See Also:

setResourceBaseName(java.lang.String)

addElement

protected void addElement(String elementName,
              String parentName,
              int childPolicy)

Adds a new element type to this metadata document format with a child policy other than CHILD_POLICY_REPEAT.

Parameters:

elementName - the name of the new element.

parentName - the name of the element that will be the parent of the new element.

childPolicy - one of the CHILD_POLICY_* constants, other than CHILD_POLICY_REPEAT, indicating the child policy of the new element.

Throws:

IllegalArgumentException - if parentName is null, or is not a legal element name for this format.

IllegalArgumentException - if childPolicy is not one of the predefined constants.

addElement

protected void addElement(String elementName,
              String parentName,
              int minChildren,
              int maxChildren)

Adds a new element type to this metadata document format with a child policy of CHILD_POLICY_REPEAT.

Parameters:

elementName - the name of the new element.

parentName - the name of the element that will be the parent of the new element.

minChildren - the minimum number of children of the node.

maxChildren - the maximum number of children of the node.

Throws:

IllegalArgumentException - if parentName is null, or is not a legal element name for this format.

IllegalArgumentException - if minChildren is negative or larger than maxChildren.

addChildElement

protected void addChildElement(String elementName,
                   String parentName)

Adds an existing element to the list of legal children for a given parent node type.

Parameters:

parentName - the name of the element that will be the new parent of the element.

elementName - the name of the element to be addded as a child.

Throws:

IllegalArgumentException - if elementName is null, or is not a legal element name for this format.

IllegalArgumentException - if parentName is null, or is not a legal element name for this format.

removeElement

protected void removeElement(String elementName)

Removes an element from the format. If no element with the given name was present, nothing happens and no exception is thrown.

Parameters:

elementName - the name of the element to be removed.

addAttribute

protected void addAttribute(String elementName,
                String attrName,
                int dataType,
                boolean required,
                String defaultValue)

Adds a new attribute to a previously defined element that may be set to an arbitrary value.

Parameters:

elementName - the name of the element.

attrName - the name of the attribute being added.

dataType - the data type (string format) of the attribute, one of the DATATYPE_* constants.

required - true if the attribute must be present.

defaultValue - the default value for the attribute, or null.

Throws:

IllegalArgumentException - if elementName is null, or is not a legal element name for this format.

IllegalArgumentException - if attrName is null.

IllegalArgumentException - if dataType is not one of the predefined constants.

addAttribute

protected void addAttribute(String elementName,
                String attrName,
                int dataType,
                boolean required,
                String defaultValue,
                List<String> enumeratedValues)

Adds a new attribute to a previously defined element that will be defined by a set of enumerated values.

Parameters:

elementName - the name of the element.

attrName - the name of the attribute being added.

dataType - the data type (string format) of the attribute, one of the DATATYPE_* constants.

required - true if the attribute must be present.

defaultValue - the default value for the attribute, or null.

enumeratedValues - a List of Strings containing the legal values for the attribute.

Throws:

IllegalArgumentException - if elementName is null, or is not a legal element name for this format.

IllegalArgumentException - if attrName is null.

IllegalArgumentException - if dataType is not one of the predefined constants.

IllegalArgumentException - if enumeratedValues is null.

IllegalArgumentException - if enumeratedValues does not contain at least one entry.

IllegalArgumentException - if enumeratedValues contains an element that is not a String or is null.

addAttribute

protected void addAttribute(String elementName,
                String attrName,
                int dataType,
                boolean required,
                String defaultValue,
                String minValue,
                String maxValue,
                boolean minInclusive,
                boolean maxInclusive)

Adds a new attribute to a previously defined element that will be defined by a range of values.

Parameters:

elementName - the name of the element.

attrName - the name of the attribute being added.

dataType - the data type (string format) of the attribute, one of the DATATYPE_* constants.

required - true if the attribute must be present.

defaultValue - the default value for the attribute, or null.

minValue - the smallest (inclusive or exclusive depending on the value of minInclusive) legal value for the attribute, as a String.

maxValue - the largest (inclusive or exclusive depending on the value of minInclusive) legal value for the attribute, as a String.

minInclusive - true if minValue is inclusive.

maxInclusive - true if maxValue is inclusive.

Throws:

IllegalArgumentException - if elementName is null, or is not a legal element name for this format.

IllegalArgumentException - if attrName is null.

IllegalArgumentException - if dataType is not one of the predefined constants.

addAttribute

protected void addAttribute(String elementName,
                String attrName,
                int dataType,
                boolean required,
                int listMinLength,
                int listMaxLength)

Adds a new attribute to a previously defined element that will be defined by a list of values.

Parameters:

elementName - the name of the element.

attrName - the name of the attribute being added.

dataType - the data type (string format) of the attribute, one of the DATATYPE_* constants.

required - true if the attribute must be present.

listMinLength - the smallest legal number of list items.

listMaxLength - the largest legal number of list items.

Throws:

IllegalArgumentException - if elementName is null, or is not a legal element name for this format.

IllegalArgumentException - if attrName is null.

IllegalArgumentException - if dataType is not one of the predefined constants.

IllegalArgumentException - if listMinLength is negative or larger than listMaxLength.

addBooleanAttribute

protected void addBooleanAttribute(String elementName,
                       String attrName,
                       boolean hasDefaultValue,
                       boolean defaultValue)

Adds a new attribute to a previously defined element that will be defined by the enumerated values TRUE and FALSE, with a datatype of DATATYPE_BOOLEAN.

Parameters:

elementName - the name of the element.

attrName - the name of the attribute being added.

hasDefaultValue - true if a default value should be present.

defaultValue - the default value for the attribute as a boolean, ignored if hasDefaultValue is false.

Throws:

IllegalArgumentException - if elementName is null, or is not a legal element name for this format.

IllegalArgumentException - if attrName is null.

removeAttribute

protected void removeAttribute(String elementName,
                   String attrName)

Removes an attribute from a previously defined element. If no attribute with the given name was present in the given element, nothing happens and no exception is thrown.

Parameters:

elementName - the name of the element.

attrName - the name of the attribute being removed.

Throws:

IllegalArgumentException - if elementName is null, or is not a legal element name for this format.

addObjectValue

protected <T> void addObjectValue(String elementName,
                      Class<T> classType,
                      boolean required,
                      T defaultValue)

Allows an Object reference of a given class type to be stored in nodes implementing the named element. The value of the Object is unconstrained other than by its class type.

If an Object reference was previously allowed, the previous settings are overwritten.

Parameters:

elementName - the name of the element.

classType - a Class variable indicating the legal class type for the object value.

required - true if an object value must be present.

defaultValue - the default value for the Object reference, or null.

Throws:

IllegalArgumentException - if elementName is null, or is not a legal element name for this format.

addObjectValue

protected <T> void addObjectValue(String elementName,
                      Class<T> classType,
                      boolean required,
                      T defaultValue,
                      List<? extends T> enumeratedValues)

Allows an Object reference of a given class type to be stored in nodes implementing the named element. The value of the Object must be one of the values given by enumeratedValues.

If an Object reference was previously allowed, the previous settings are overwritten.

Parameters:

elementName - the name of the element.

classType - a Class variable indicating the legal class type for the object value.

required - true if an object value must be present.

defaultValue - the default value for the Object reference, or null.

enumeratedValues - a List of Objects containing the legal values for the object reference.

Throws:

IllegalArgumentException - if elementName is null, or is not a legal element name for this format.

IllegalArgumentException - if enumeratedValues is null.

IllegalArgumentException - if enumeratedValues does not contain at least one entry.

IllegalArgumentException - if enumeratedValues contains an element that is not an instance of the class type denoted by classType or is null.

addObjectValue

protected <T extends Object & Comparable<? super T>> void addObjectValue(String elementName,
                                                            Class<T> classType,
                                                            T defaultValue,
                                                            Comparable<? super T> minValue,
                                                            Comparable<? super T> maxValue,
                                                            boolean minInclusive,
                                                            boolean maxInclusive)

Allows an Object reference of a given class type to be stored in nodes implementing the named element. The value of the Object must be within the range given by minValue and maxValue. Furthermore, the class type must implement the Comparable interface.

If an Object reference was previously allowed, the previous settings are overwritten.

Parameters:

elementName - the name of the element.

classType - a Class variable indicating the legal class type for the object value.

defaultValue - the default value for the

minValue - the smallest (inclusive or exclusive depending on the value of minInclusive) legal value for the object value, as a String.

maxValue - the largest (inclusive or exclusive depending on the value of minInclusive) legal value for the object value, as a String.

minInclusive - true if minValue is inclusive.

maxInclusive - true if maxValue is inclusive.

Throws:

IllegalArgumentException - if elementName is null, or is not a legal element name for this format.

addObjectValue

protected void addObjectValue(String elementName,
                  Class<?> classType,
                  int arrayMinLength,
                  int arrayMaxLength)

Allows an Object reference of a given class type to be stored in nodes implementing the named element. The value of the Object must an array of objects of class type given by classType, with at least arrayMinLength and at most arrayMaxLength elements.

If an Object reference was previously allowed, the previous settings are overwritten.

Parameters:

elementName - the name of the element.

classType - a Class variable indicating the legal class type for the object value.

arrayMinLength - the smallest legal length for the array.

arrayMaxLength - the largest legal length for the array.

Throws:

IllegalArgumentException - if elementName is not a legal element name for this format.

removeObjectValue

protected void removeObjectValue(String elementName)

Disallows an Object reference from being stored in nodes implementing the named element.

Parameters:

elementName - the name of the element.

Throws:

IllegalArgumentException - if elementName is not a legal element name for this format.

getRootName

public String getRootName()

Description copied from interface: IIOMetadataFormat

Returns the name of the root element of the format.

Specified by:

getRootName in interface IIOMetadataFormat

Returns:

a String.

canNodeAppear

public abstract boolean canNodeAppear(String elementName,
                    ImageTypeSpecifier imageType)

Description copied from interface: IIOMetadataFormat

Returns true if the element (and the subtree below it) is allowed to appear in a metadata document for an image of the given type, defined by an ImageTypeSpecifier. For example, a metadata document format might contain an element that describes the primary colors of the image, which would not be allowed when writing a grayscale image.

Specified by:

canNodeAppear in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

imageType - an ImageTypeSpecifier indicating the type of the image that will be associated with the metadata.

Returns:

true if the node is meaningful for images of the given type.

getElementMinChildren

public int getElementMinChildren(String elementName)

Description copied from interface: IIOMetadataFormat

Returns the minimum number of children of the named element with child policy CHILD_POLICY_REPEAT. For example, an element representing color primary information might be required to have at least 3 children, one for each primay.

Specified by:

getElementMinChildren in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

Returns:

an int.

getElementMaxChildren

public int getElementMaxChildren(String elementName)

Description copied from interface: IIOMetadataFormat

Returns the maximum number of children of the named element with child policy CHILD_POLICY_REPEAT. For example, an element representing an entry in an 8-bit color palette might be allowed to repeat up to 256 times. A value of Integer.MAX_VALUE may be used to specify that there is no upper bound.

Specified by:

getElementMaxChildren in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

Returns:

an int.

getElementDescription

public String getElementDescription(String elementName,
                           Locale locale)

Returns a String containing a description of the named element, or null. The desciption will be localized for the supplied Locale if possible.

The default implementation will first locate a ResourceBundle using the current resource base name set by setResourceBaseName and the supplied Locale, using the fallback mechanism described in the comments for ResourceBundle.getBundle. If a ResourceBundle is found, the element name will be used as a key to its getString method, and the result returned. If no ResourceBundle is found, or no such key is present, null will be returned.

If locale is null, the current default Locale returned by Locale.getLocale will be used.

Specified by:

getElementDescription in interface IIOMetadataFormat

Parameters:

elementName - the name of the element.

locale - the Locale for which localization will be attempted.

Returns:

the element description.

Throws:

IllegalArgumentException - if elementName is null, or is not a legal element name for this format.

See Also:

setResourceBaseName(java.lang.String)

getChildPolicy

public int getChildPolicy(String elementName)

Description copied from interface: IIOMetadataFormat

Returns one of the constants starting with CHILD_POLICY_, indicating the legal pattern of children for the named element.

Specified by:

getChildPolicy in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

Returns:

one of the CHILD_POLICY_* constants.

getChildNames

public String[] getChildNames(String elementName)

Description copied from interface: IIOMetadataFormat

Returns an array of Strings indicating the names of the element which are allowed to be children of the named element, in the order in which they should appear. If the element cannot have children, null is returned.

Specified by:

getChildNames in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

Returns:

an array of Strings, or null.

getAttributeNames

public String[] getAttributeNames(String elementName)

Description copied from interface: IIOMetadataFormat

Returns an array of Strings listing the names of the attributes that may be associated with the named element.

Specified by:

getAttributeNames in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

Returns:

an array of Strings.

getAttributeValueType

public int getAttributeValueType(String elementName,
                        String attrName)

Description copied from interface: IIOMetadataFormat

Returns one of the constants starting with VALUE_, indicating whether the values of the given attribute within the named element are arbitrary, constrained to lie within a specified range, constrained to be one of a set of enumerated values, or are a whitespace-separated list of arbitrary values.

Specified by:

getAttributeValueType in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

attrName - the name of the attribute being queried.

Returns:

one of the VALUE_* constants.

getAttributeDataType

public int getAttributeDataType(String elementName,
                       String attrName)

Description copied from interface: IIOMetadataFormat

Returns one of the constants starting with DATATYPE_, indicating the format and interpretation of the value of the given attribute within th enamed element. If getAttributeValueType returns VALUE_LIST, then the legal value is a whitespace-spearated list of values of the returned datatype.

Specified by:

getAttributeDataType in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

attrName - the name of the attribute being queried.

Returns:

one of the DATATYPE_* constants.

isAttributeRequired

public boolean isAttributeRequired(String elementName,
                          String attrName)

Description copied from interface: IIOMetadataFormat

Returns true if the named attribute must be present within the named element.

Specified by:

isAttributeRequired in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

attrName - the name of the attribute being queried.

Returns:

true if the attribut must be present.

getAttributeDefaultValue

public String getAttributeDefaultValue(String elementName,
                              String attrName)

Description copied from interface: IIOMetadataFormat

Returns the default value of the named attribute, if it is not explictly present within the named element, as a String, or null if no default value is available.

Specified by:

getAttributeDefaultValue in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

attrName - the name of the attribute being queried.

Returns:

a String containing the default value, or null.

getAttributeEnumerations

public String[] getAttributeEnumerations(String elementName,
                                String attrName)

Description copied from interface: IIOMetadataFormat

Returns an array of Strings containing the legal enumerated values for the given attribute within the named element. This method should only be called if getAttributeValueType returns VALUE_ENUMERATION.

Specified by:

getAttributeEnumerations in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

attrName - the name of the attribute being queried.

Returns:

an array of Strings.

getAttributeMinValue

public String getAttributeMinValue(String elementName,
                          String attrName)

Description copied from interface: IIOMetadataFormat

Returns the minimum legal value for the attribute. Whether this value is inclusive or exclusive may be determined by the value of getAttributeValueType. The value is returned as a String; its interpretation is dependent on the value of getAttributeDataType. This method should only be called if getAttributeValueType returns VALUE_RANGE_*.

Specified by:

getAttributeMinValue in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

attrName - the name of the attribute being queried.

Returns:

a String containing the smallest legal value for the attribute.

getAttributeMaxValue

public String getAttributeMaxValue(String elementName,
                          String attrName)

Description copied from interface: IIOMetadataFormat

Returns the maximum legal value for the attribute. Whether this value is inclusive or exclusive may be determined by the value of getAttributeValueType. The value is returned as a String; its interpretation is dependent on the value of getAttributeDataType. This method should only be called if getAttributeValueType returns VALUE_RANGE_*.

Specified by:

getAttributeMaxValue in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried, as a String.

attrName - the name of the attribute being queried.

Returns:

a String containing the largest legal value for the attribute.

getAttributeListMinLength

public int getAttributeListMinLength(String elementName,
                            String attrName)

Description copied from interface: IIOMetadataFormat

Returns the minimum number of list items that may be used to define this attribute. The attribute itself is defined as a String containing multiple whitespace-separated items. This method should only be called if getAttributeValueType returns VALUE_LIST.

Specified by:

getAttributeListMinLength in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

attrName - the name of the attribute being queried.

Returns:

the smallest legal number of list items for the attribute.

getAttributeListMaxLength

public int getAttributeListMaxLength(String elementName,
                            String attrName)

Description copied from interface: IIOMetadataFormat

Returns the maximum number of list items that may be used to define this attribute. A value of Integer.MAX_VALUE may be used to specify that there is no upper bound. The attribute itself is defined as a String containing multiple whitespace-separated items. This method should only be called if getAttributeValueType returns VALUE_LIST.

Specified by:

getAttributeListMaxLength in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

attrName - the name of the attribute being queried.

Returns:

the largest legal number of list items for the attribute.

getAttributeDescription

public String getAttributeDescription(String elementName,
                             String attrName,
                             Locale locale)

Returns a String containing a description of the named attribute, or null. The desciption will be localized for the supplied Locale if possible.

The default implementation will first locate a ResourceBundle using the current resource base name set by setResourceBaseName and the supplied Locale, using the fallback mechanism described in the comments for ResourceBundle.getBundle. If a ResourceBundle is found, the element name followed by a "/" character followed by the attribute name (elementName + "/" + attrName) will be used as a key to its getString method, and the result returned. If no ResourceBundle is found, or no such key is present, null will be returned.

If locale is null, the current default Locale returned by Locale.getLocale will be used.

Specified by:

getAttributeDescription in interface IIOMetadataFormat

Parameters:

elementName - the name of the element.

attrName - the name of the attribute.

locale - the Locale for which localization will be attempted, or null.

Returns:

the attribute description.

Throws:

IllegalArgumentException - if elementName is null, or is not a legal element name for this format.

IllegalArgumentException - if attrName is null or is not a legal attribute name for this element.

See Also:

setResourceBaseName(java.lang.String)

getObjectValueType

public int getObjectValueType(String elementName)

Description copied from interface: IIOMetadataFormat

Returns one of the enumerated values starting with VALUE_, indicating the type of values (enumeration, range, or array) that are allowed for the Object reference. If no object value can be stored within the given element, the result of this method will be VALUE_NONE.

Object references whose legal values are defined as a range must implement the Comparable interface.

Specified by:

getObjectValueType in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

Returns:

one of the VALUE_* constants.

See Also:

Comparable

getObjectClass

public Class<?> getObjectClass(String elementName)

Description copied from interface: IIOMetadataFormat

Returns the Class type of the Object reference stored within the element. If this element may not contain an Object reference, an IllegalArgumentException will be thrown. If the class type is an array, this field indicates the underlying class type (e.g, for an array of ints, this method would return int.class).

Object references whose legal values are defined as a range must implement the Comparable interface.

Specified by:

getObjectClass in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

Returns:

a Class object.

getObjectDefaultValue

public Object getObjectDefaultValue(String elementName)

Description copied from interface: IIOMetadataFormat

Returns an Objects containing the default value for the Object reference within the named element.

Specified by:

getObjectDefaultValue in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

Returns:

an Object.

getObjectEnumerations

public Object[] getObjectEnumerations(String elementName)

Description copied from interface: IIOMetadataFormat

Returns an array of Objects containing the legal enumerated values for the Object reference within the named element. This method should only be called if getObjectValueType returns VALUE_ENUMERATION.

The Object associated with a node that accepts emuerated values must be equal to one of the values returned by this method, as defined by the == operator (as opposed to the Object.equals method).

Specified by:

getObjectEnumerations in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

Returns:

an array of Objects.

getObjectMinValue

public Comparable<?> getObjectMinValue(String elementName)

Description copied from interface: IIOMetadataFormat

Returns the minimum legal value for the Object reference within the named element. Whether this value is inclusive or exclusive may be determined by the value of getObjectValueType. This method should only be called if getObjectValueType returns one of the constants starting with VALUE_RANGE.

Specified by:

getObjectMinValue in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

Returns:

the smallest legal value for the attribute.

getObjectMaxValue

public Comparable<?> getObjectMaxValue(String elementName)

Description copied from interface: IIOMetadataFormat

Returns the maximum legal value for the Object reference within the named element. Whether this value is inclusive or exclusive may be determined by the value of getObjectValueType. This method should only be called if getObjectValueType returns one of the constants starting with VALUE_RANGE.

Specified by:

getObjectMaxValue in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

Returns:

the smallest legal value for the attribute.

getObjectArrayMinLength

public int getObjectArrayMinLength(String elementName)

Description copied from interface: IIOMetadataFormat

Returns the minimum number of array elements that may be used to define the Object reference within the named element. This method should only be called if getObjectValueType returns VALUE_LIST.

Specified by:

getObjectArrayMinLength in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

Returns:

the smallest valid array length for the Object reference.

getObjectArrayMaxLength

public int getObjectArrayMaxLength(String elementName)

Description copied from interface: IIOMetadataFormat

Returns the maximum number of array elements that may be used to define the Object reference within the named element. A value of Integer.MAX_VALUE may be used to specify that there is no upper bound. This method should only be called if getObjectValueType returns VALUE_LIST.

Specified by:

getObjectArrayMaxLength in interface IIOMetadataFormat

Parameters:

elementName - the name of the element being queried.

Returns:

the largest valid array length for the Object reference.

getStandardFormatInstance

public static IIOMetadataFormat getStandardFormatInstance()

Returns an IIOMetadataFormat object describing the standard, plug-in neutral javax.imageio_1.0 metadata document format described in the comment of the javax.imageio.metadata package.

Returns:

a predefined IIOMetadataFormat instance.