/*
* Copyright (c) 2000, 2004, Oracle and/or its affiliates. All rights reserved.
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*
*
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*
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*
*
*
*
*/
package javax.imageio.metadata;
import java.util.Locale;
import javax.imageio.ImageTypeSpecifier;
/**
* An object describing the structure of metadata documents returned
* from IIOMetadata.getAsTree
and passed to
* IIOMetadata.setFromTree
and mergeTree
.
* Document structures are described by a set of constraints on the
* type and number of child elements that may belong to a given parent
* element type, the names, types, and values of attributes that may
* belong to an element, and the type and values of
* Object
reference that may be stored at a node.
*
*
N.B: classes that implement this interface should contain a
* method declared as public static getInstance()
which
* returns an instance of the class. Commonly, an implentation will
* construct only a single instance and cache it for future
* invocations of getInstance
.
*
*
The structures that may be described by this class are a subset
* of those expressible using XML document type definitions (DTDs),
* with the addition of some basic information on the datatypes of
* attributes and the ability to store an Object
* reference within a node. In the future, XML Schemas could be used
* to represent these structures, and many others.
*
*
The differences between
* IIOMetadataFormat
-described structures and DTDs are as
* follows:
*
*
CHILD_*
constants;
*
* Object
. There is no provision for
* representing such objects textually.
* getChildPolicy
to indicate
* that an element may not have any children. In other words, it
* is required to be a leaf node.
*/
int CHILD_POLICY_EMPTY = 0;
/**
* A constant returned by getChildPolicy
to indicate
* that an element must have a single instance of each of its
* legal child elements, in order. In DTD terms, the contents of
* the element are defined by a sequence a,b,c,d,...
.
*/
int CHILD_POLICY_ALL = 1;
/**
* A constant returned by getChildPolicy
to indicate
* that an element must have zero or one instance of each of its
* legal child elements, in order. In DTD terms, the contents of
* the element are defined by a sequence
* a?,b?,c?,d?,...
.
*/
int CHILD_POLICY_SOME = 2;
/**
* A constant returned by getChildPolicy
to indicate
* that an element must have zero or one children, selected from
* among its legal child elements. In DTD terms, the contents of
* the element are defined by a selection
* a|b|c|d|...
.
*/
int CHILD_POLICY_CHOICE = 3;
/**
* A constant returned by getChildPolicy
to indicate
* that an element must have a sequence of instances of any of its
* legal child elements. In DTD terms, the contents of the
* element are defined by a sequence (a|b|c|d|...)*
.
*/
int CHILD_POLICY_SEQUENCE = 4;
/**
* A constant returned by getChildPolicy
to indicate
* that an element must have zero or more instances of its unique
* legal child element. In DTD terms, the contents of the element
* are defined by a starred expression a*
.
*/
int CHILD_POLICY_REPEAT = 5;
/**
* The largest valid CHILD_POLICY_*
constant,
* to be used for range checks.
*/
int CHILD_POLICY_MAX = CHILD_POLICY_REPEAT;
/**
* A constant returned by getObjectValueType
to
* indicate the absence of a user object.
*/
int VALUE_NONE = 0;
/**
* A constant returned by getAttributeValueType
and
* getObjectValueType
to indicate that the attribute
* or user object may be set a single, arbitrary value.
*/
int VALUE_ARBITRARY = 1;
/**
* A constant returned by getAttributeValueType
and
* getObjectValueType
to indicate that the attribute
* or user object may be set a range of values. Both the minimum
* and maximum values of the range are exclusive. It is
* recommended that ranges of integers be inclusive on both ends,
* and that exclusive ranges be used only for floating-point data.
*
* @see #VALUE_RANGE_MIN_MAX_INCLUSIVE
*/
int VALUE_RANGE = 2;
/**
* A value that may be or'ed with VALUE_RANGE
to
* obtain VALUE_RANGE_MIN_INCLUSIVE
, and with
* VALUE_RANGE_MAX_INCLUSIVE
to obtain
* VALUE_RANGE_MIN_MAX_INCLUSIVE
.
*
* Similarly, the value may be and'ed with the value of
* getAttributeValueType
or
* getObjectValueType
to determine if the minimum
* value of the range is inclusive.
*/
int VALUE_RANGE_MIN_INCLUSIVE_MASK = 4;
/**
* A value that may be or'ed with VALUE_RANGE
to
* obtain VALUE_RANGE_MAX_INCLUSIVE
, and with
* VALUE_RANGE_MIN_INCLUSIVE
to obtain
* VALUE_RANGE_MIN_MAX_INCLUSIVE
.
*
*
Similarly, the value may be and'ed with the value of
* getAttributeValueType
or
* getObjectValueType
to determine if the maximum
* value of the range is inclusive.
*/
int VALUE_RANGE_MAX_INCLUSIVE_MASK = 8;
/**
* A constant returned by getAttributeValueType
and
* getObjectValueType
to indicate that the attribute
* or user object may be set to a range of values. The minimum
* (but not the maximum) value of the range is inclusive.
*/
int VALUE_RANGE_MIN_INCLUSIVE = VALUE_RANGE |
VALUE_RANGE_MIN_INCLUSIVE_MASK;
/**
* A constant returned by getAttributeValueType
and
* getObjectValueType
to indicate that the attribute
* or user object may be set to a range of values. The maximum
* (but not the minimum) value of the range is inclusive.
*/
int VALUE_RANGE_MAX_INCLUSIVE = VALUE_RANGE |
VALUE_RANGE_MAX_INCLUSIVE_MASK;
/**
* A constant returned by getAttributeValueType
and
* getObjectValueType
to indicate that the attribute
* or user object may be set a range of values. Both the minimum
* and maximum values of the range are inclusive. It is
* recommended that ranges of integers be inclusive on both ends,
* and that exclusive ranges be used only for floating-point data.
*/
int VALUE_RANGE_MIN_MAX_INCLUSIVE =
VALUE_RANGE |
VALUE_RANGE_MIN_INCLUSIVE_MASK |
VALUE_RANGE_MAX_INCLUSIVE_MASK;
/**
* A constant returned by getAttributeValueType
and
* getObjectValueType
to indicate that the attribute
* or user object may be set one of a number of enumerated values.
* In the case of attributes, these values are
* String
s; for objects, they are
* Object
s implementing a given class or interface.
*
*
Attribute values of type DATATYPE_BOOLEAN
* should be marked as enumerations.
*/
int VALUE_ENUMERATION = 16;
/**
* A constant returned by getAttributeValueType
and
* getObjectValueType
to indicate that the attribute
* or user object may be set to a list or array of values. In the
* case of attributes, the list will consist of
* whitespace-separated values within a String
; for
* objects, an array will be used.
*/
int VALUE_LIST = 32;
/**
* A constant returned by getAttributeDataType
* indicating that the value of an attribute is a general Unicode
* string.
*/
int DATATYPE_STRING = 0;
/**
* A constant returned by getAttributeDataType
* indicating that the value of an attribute is one of the boolean
* values 'true' or 'false'.
* Attribute values of type DATATYPE_BOOLEAN should be marked as
* enumerations, and the permitted values should be the string
* literal values "TRUE" or "FALSE", although a plugin may also
* recognise lower or mixed case equivalents.
*/
int DATATYPE_BOOLEAN = 1;
/**
* A constant returned by getAttributeDataType
* indicating that the value of an attribute is a string
* representation of an integer.
*/
int DATATYPE_INTEGER = 2;
/**
* A constant returned by getAttributeDataType
* indicating that the value of an attribute is a string
* representation of a decimal floating-point number.
*/
int DATATYPE_FLOAT = 3;
/**
* A constant returned by getAttributeDataType
* indicating that the value of an attribute is a string
* representation of a double-precision decimal floating-point
* number.
*/
int DATATYPE_DOUBLE = 4;
// Root
/**
* Returns the name of the root element of the format.
*
* @return a String
.
*/
String getRootName();
// Multiplicity
/**
* 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.
*
* @param elementName the name of the element being queried.
* @param imageType an ImageTypeSpecifier
indicating
* the type of the image that will be associated with the
* metadata.
*
* @return true
if the node is meaningful for images
* of the given type.
*/
boolean canNodeAppear(String elementName, ImageTypeSpecifier imageType);
/**
* 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.
*
* @param elementName the name of the element being queried.
*
* @return an int
.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if the named element does
* not have a child policy of CHILD_POLICY_REPEAT
.
*/
int getElementMinChildren(String elementName);
/**
* 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.
*
* @param elementName the name of the element being queried.
*
* @return an int
.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if the named element does
* not have a child policy of CHILD_POLICY_REPEAT
.
*/
int getElementMaxChildren(String elementName);
/**
* Returns a String
containing a description of the
* named element, or null
. The desciption will be
* localized for the supplied Locale
if possible.
*
*
If locale
is null
, the current
* default Locale
returned by Locale.getLocale
* will be used.
*
* @param elementName the name of the element.
* @param locale the Locale
for which localization
* will be attempted.
*
* @return the element description.
*
* @exception IllegalArgumentException if elementName
* is null
, or is not a legal element name for this format.
*/
String getElementDescription(String elementName, Locale locale);
// Children
/**
* Returns one of the constants starting with
* CHILD_POLICY_
, indicating the legal pattern of
* children for the named element.
*
* @param elementName the name of the element being queried.
*
* @return one of the CHILD_POLICY_*
constants.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
*/
int getChildPolicy(String elementName);
/**
* Returns an array of String
s 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.
*
* @param elementName the name of the element being queried.
*
* @return an array of String
s, or null.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
*/
String[] getChildNames(String elementName);
// Attributes
/**
* Returns an array of String
s listing the names of
* the attributes that may be associated with the named element.
*
* @param elementName the name of the element being queried.
*
* @return an array of String
s.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
*/
String[] getAttributeNames(String elementName);
/**
* 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.
*
* @param elementName the name of the element being queried.
* @param attrName the name of the attribute being queried.
*
* @return one of the VALUE_*
constants.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if attrName
is
* null
or is not a legal attribute name for this
* element.
*/
int getAttributeValueType(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. If getAttributeValueType
returns
* VALUE_LIST
, then the legal value is a
* whitespace-spearated list of values of the returned datatype.
*
* @param elementName the name of the element being queried.
* @param attrName the name of the attribute being queried.
*
* @return one of the DATATYPE_*
constants.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if attrName
is
* null
or is not a legal attribute name for this
* element.
*/
int getAttributeDataType(String elementName, String attrName);
/**
* Returns true
if the named attribute must be
* present within the named element.
*
* @param elementName the name of the element being queried.
* @param attrName the name of the attribute being queried.
*
* @return true
if the attribut must be present.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if attrName
is
* null
or is not a legal attribute name for this
* element.
*/
boolean isAttributeRequired(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.
*
* @param elementName the name of the element being queried.
* @param attrName the name of the attribute being queried.
*
* @return a String
containing the default value, or
* null
.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if attrName
is
* null
or is not a legal attribute name for this
* element.
*/
String getAttributeDefaultValue(String elementName, String attrName);
/**
* Returns an array of String
s containing the legal
* enumerated values for the given attribute within the named
* element. This method should only be called if
* getAttributeValueType
returns
* VALUE_ENUMERATION
.
*
* @param elementName the name of the element being queried.
* @param attrName the name of the attribute being queried.
*
* @return an array of String
s.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if attrName
is
* null
or is not a legal attribute name for this
* element.
* @exception IllegalArgumentException if the given attribute is
* not defined as an enumeration.
*/
String[] getAttributeEnumerations(String elementName, String attrName);
/**
* 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_*
.
*
* @param elementName the name of the element being queried.
* @param attrName the name of the attribute being queried.
*
* @return a String
containing the smallest legal
* value for the attribute.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if attrName
is
* null
or is not a legal attribute name for this
* element.
* @exception IllegalArgumentException if the given attribute is
* not defined as a range.
*/
String getAttributeMinValue(String elementName, String attrName);
/**
* 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_*
.
*
* @param elementName the name of the element being queried, as a
* String
.
* @param attrName the name of the attribute being queried.
*
* @return a String
containing the largest legal
* value for the attribute.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if attrName
is
* null
or is not a legal attribute name for this
* element.
* @exception IllegalArgumentException if the given attribute is
* not defined as a range.
*/
String getAttributeMaxValue(String elementName, String attrName);
/**
* 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
.
*
* @param elementName the name of the element being queried.
* @param attrName the name of the attribute being queried.
*
* @return the smallest legal number of list items for the
* attribute.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if attrName
is
* null
or is not a legal attribute name for this
* element.
* @exception IllegalArgumentException if the given attribute is
* not defined as a list.
*/
int getAttributeListMinLength(String elementName, String attrName);
/**
* 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
.
*
* @param elementName the name of the element being queried.
* @param attrName the name of the attribute being queried.
*
* @return the largest legal number of list items for the
* attribute.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if attrName
is
* null
or is not a legal attribute name for this
* element.
* @exception IllegalArgumentException if the given attribute is
* not defined as a list.
*/
int getAttributeListMaxLength(String elementName, String attrName);
/**
* Returns a String
containing a description of the
* named attribute, or null
. The desciption will be
* localized for the supplied Locale
if possible.
*
*
If locale
is null
, the current
* default Locale
returned by Locale.getLocale
* will be used.
*
* @param elementName the name of the element.
* @param attrName the name of the attribute.
* @param locale the Locale
for which localization
* will be attempted.
*
* @return the attribute description.
*
* @exception IllegalArgumentException if elementName
* is null
, or is not a legal element name for this format.
* @exception IllegalArgumentException if attrName
is
* null
or is not a legal attribute name for this
* element.
*/
String getAttributeDescription(String elementName, String attrName,
Locale locale);
// Object value
/**
* 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.
*
* @param elementName the name of the element being queried.
*
* @return one of the VALUE_*
constants.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
*
* @see Comparable
*/
int getObjectValueType(String elementName);
/**
* 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 int
s, this
* method would return int.class
).
*
*
Object
references whose legal values are
* defined as a range must implement the Comparable
* interface.
*
* @param elementName the name of the element being queried.
*
* @return a Class
object.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if the named element cannot
* contain an object value (i.e., if
* getObjectValueType(elementName) == VALUE_NONE
).
*/
Class> getObjectClass(String elementName);
/**
* Returns an Object
s containing the default
* value for the Object
reference within
* the named element.
*
* @param elementName the name of the element being queried.
*
* @return an Object
.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if the named element cannot
* contain an object value (i.e., if
* getObjectValueType(elementName) == VALUE_NONE
).
*/
Object getObjectDefaultValue(String elementName);
/**
* Returns an array of Object
s 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).
*
* @param elementName the name of the element being queried.
*
* @return an array of Object
s.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if the named element cannot
* contain an object value (i.e., if
* getObjectValueType(elementName) == VALUE_NONE
).
* @exception IllegalArgumentException if the Object
* is not defined as an enumeration.
*/
Object[] getObjectEnumerations(String elementName);
/**
* 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
.
*
* @param elementName the name of the element being queried.
*
* @return the smallest legal value for the attribute.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if the named element cannot
* contain an object value (i.e., if
* getObjectValueType(elementName) == VALUE_NONE
).
* @exception IllegalArgumentException if the Object
* is not defined as a range.
*/
Comparable> getObjectMinValue(String elementName);
/**
* 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
.
*
* @return the smallest legal value for the attribute.
*
* @param elementName the name of the element being queried.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if the named element cannot
* contain an object value (i.e., if
* getObjectValueType(elementName) == VALUE_NONE
).
* @exception IllegalArgumentException if the Object
* is not defined as a range.
*/
Comparable> getObjectMaxValue(String elementName);
/**
* 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
.
*
* @param elementName the name of the element being queried.
*
* @return the smallest valid array length for the
* Object
reference.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if the named element cannot
* contain an object value (i.e., if
* getObjectValueType(elementName) == VALUE_NONE
).
* @exception IllegalArgumentException if the Object
is not
* an array.
*/
int getObjectArrayMinLength(String elementName);
/**
* 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
.
*
* @param elementName the name of the element being queried.
*
* @return the largest valid array length for the
* Object
reference.
*
* @exception IllegalArgumentException if elementName
* is null
or is not a legal element name for this
* format.
* @exception IllegalArgumentException if the named element cannot
* contain an object value (i.e., if
* getObjectValueType(elementName) == VALUE_NONE
).
* @exception IllegalArgumentException if the Object
is not
* an array.
*/
int getObjectArrayMaxLength(String elementName);
}