https://openjdk.java.net/ 
/*
 * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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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 implementation will construct only a single instance and cache it for future invocations of getInstance. 
 In the event that the plugin is provided as part of a named module,
that module must export the package containing the implementation class
to the 
java.desktop
 module via a qualified export.
An unqualified export is not recommended unless also needed for
some other reason. Failing to export the package will result in
access failure at runtime.

 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: 
    

  •  Elements may not contain text or mix text with embedded
tags.

  •  The children of an element must conform to one of a few simple patterns, described in the documentation for the CHILD_* constants; 
  •  The in-memory representation of an elements may contain a reference to an Object. There is no provision for representing such objects textually. 


/**
 * An object describing the structure of metadata documents returned
 * from {@code IIOMetadata.getAsTree} and passed to
 * {@code IIOMetadata.setFromTree} and {@code 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
 * {@code Object} reference that may be stored at a node.
 *
 * <p> N.B: classes that implement this interface should contain a
 * method declared as {@code public static getInstance()} which
 * returns an instance of the class.  Commonly, an implementation will
 * construct only a single instance and cache it for future
 * invocations of {@code getInstance}.
 * <p> In the event that the plugin is provided as part of a named module,
 * that module must export the package containing the implementation class
 * to the <pre>java.desktop</pre> module via a qualified export.
 * An unqualified export is not recommended unless also needed for
 * some other reason. Failing to export the package will result in
 * access failure at runtime.
 *
 * <p> 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 {@code Object}
 * reference within a node.  In the future, XML Schemas could be used
 * to represent these structures, and many others.
 *
 * <p> The differences between
 * {@code IIOMetadataFormat}-described structures and DTDs are as
 * follows:
 *
 * <ul>
 * <li> Elements may not contain text or mix text with embedded
 * tags.
 *
 * <li> The children of an element must conform to one of a few simple
 * patterns, described in the documentation for the
 * {@code CHILD_*} constants;
 *
 * <li> The in-memory representation of an elements may contain a
 * reference to an {@code Object}.  There is no provision for
 * representing such objects textually.
 * </ul>
 *
 */
public interface IIOMetadataFormat {

    // Child policies

    
A constant returned by getChildPolicy to indicate that an element may not have any children. In other words, it is required to be a leaf node. 
/**
     * A constant returned by {@code 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,.... 
/**
     * A constant returned by {@code 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 {@code 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?,.... 
/**
     * A constant returned by {@code 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
     * {@code 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|.... 
/**
     * A constant returned by {@code 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
     * {@code 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|...)*. 
/**
     * A constant returned by {@code 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 {@code (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*. 
/**
     * A constant returned by {@code 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 {@code a*}.
     */
    int CHILD_POLICY_REPEAT = 5;

    
The largest valid CHILD_POLICY_* constant, to be used for range checks. 
/**
     * The largest valid {@code 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. 
/**
     * A constant returned by {@code 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. 
/**
     * A constant returned by {@code getAttributeValueType} and
     * {@code 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 Also:
/**
     * A constant returned by {@code getAttributeValueType} and
     * {@code 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. 
/**
     * A value that may be or'ed with {@code VALUE_RANGE} to
     * obtain {@code VALUE_RANGE_MIN_INCLUSIVE}, and with
     * {@code VALUE_RANGE_MAX_INCLUSIVE} to obtain
     * {@code VALUE_RANGE_MIN_MAX_INCLUSIVE}.
     *
     * <p> Similarly, the value may be and'ed with the value of
     * {@code getAttributeValueType} or
     * {@code 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. 
/**
     * A value that may be or'ed with {@code VALUE_RANGE} to
     * obtain {@code VALUE_RANGE_MAX_INCLUSIVE}, and with
     * {@code VALUE_RANGE_MIN_INCLUSIVE} to obtain
     * {@code VALUE_RANGE_MIN_MAX_INCLUSIVE}.
     *
     * <p> Similarly, the value may be and'ed with the value of
     * {@code getAttributeValueType} or
     * {@code 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. 
/**
     * A constant returned by {@code getAttributeValueType} and
     * {@code 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. 
/**
     * A constant returned by {@code getAttributeValueType} and
     * {@code 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. 
/**
     * A constant returned by {@code getAttributeValueType} and
     * {@code 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 Strings; for objects, they are Objects implementing a given class or interface. 
 Attribute values of type DATATYPE_BOOLEAN should be marked as enumerations. 
/**
     * A constant returned by {@code getAttributeValueType} and
     * {@code 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
     * {@code String}s; for objects, they are
     * {@code Object}s implementing a given class or interface.
     *
     * <p> Attribute values of type {@code 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. 
/**
     * A constant returned by {@code getAttributeValueType} and
     * {@code 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 {@code 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. 
/**
     * A constant returned by {@code 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. 
/**
     * A constant returned by {@code 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. 
/**
     * A constant returned by {@code 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. 
/**
     * A constant returned by {@code 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. 
/**
     * A constant returned by {@code 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.

Returns:a String.
/**
     * Returns the name of the root element of the format.
     *
     * @return a {@code 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. 
Params:
  • 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.
/**
     * Returns {@code 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 {@code 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 {@code ImageTypeSpecifier} indicating
     * the type of the image that will be associated with the
     * metadata.
     *
     * @return {@code 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 primary. 
Params:
  • elementName – the name of the element being queried.
Throws:
Returns:an int.
/**
     * Returns the minimum number of children of the named element
     * with child policy {@code CHILD_POLICY_REPEAT}.  For
     * example, an element representing color primary information
     * might be required to have at least 3 children, one for each
     * primary.
     *
     * @param elementName the name of the element being queried.
     *
     * @return an {@code int}.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if the named element does
     * not have a child policy of {@code 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. 
Params:
  • elementName – the name of the element being queried.
Throws:
Returns:an int.
/**
     * Returns the maximum number of children of the named element
     * with child policy {@code 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
     * {@code 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 {@code int}.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if the named element does
     * not have a child policy of {@code CHILD_POLICY_REPEAT}.
     */
    int getElementMaxChildren(String elementName);

    
Returns a String containing a description of the named element, or null. The description will be localized for the supplied Locale if possible. 
 If locale is null, the current default Locale returned by Locale.getLocale will be used. 
Params:
  • elementName – the name of the element.
  • locale – the Locale for which localization will be attempted.
Throws:
Returns:the element description.
/**
     * Returns a {@code String} containing a description of the
     * named element, or {@code null}.  The description will be
     * localized for the supplied {@code Locale} if possible.
     *
     * <p> If {@code locale} is {@code null}, the current
     * default {@code Locale} returned by {@code Locale.getLocale}
     * will be used.
     *
     * @param elementName the name of the element.
     * @param locale the {@code Locale} for which localization
     * will be attempted.
     *
     * @return the element description.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code 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. 
Params:
  • elementName – the name of the element being queried.
Throws:
Returns:one of the CHILD_POLICY_* constants.
/**
     * Returns one of the constants starting with
     * {@code 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 {@code CHILD_POLICY_*} constants.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     */
    int getChildPolicy(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. If the element cannot have children, null is returned. 
Params:
  • elementName – the name of the element being queried.
Throws:
Returns:an array of Strings, or null.
/**
     * Returns an array of {@code 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, {@code null} is returned.
     *
     * @param elementName the name of the element being queried.
     *
     * @return an array of {@code String}s, or null.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     */
    String[] getChildNames(String elementName);

    // Attributes

    
Returns an array of Strings listing the names of the attributes that may be associated with the named element. 
Params:
  • elementName – the name of the element being queried.
Throws:
Returns:an array of Strings.
/**
     * Returns an array of {@code 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 {@code String}s.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code 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. 
Params:
  • elementName – the name of the element being queried.
  • attrName – the name of the attribute being queried.
Throws:
Returns:one of the VALUE_* constants.
/**
     * Returns one of the constants starting with {@code 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 {@code VALUE_*} constants.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if {@code attrName} is
     * {@code 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 the named element. If getAttributeValueType returns VALUE_LIST, then the legal value is a whitespace-spearated list of values of the returned datatype. 
Params:
  • elementName – the name of the element being queried.
  • attrName – the name of the attribute being queried.
Throws:
Returns:one of the DATATYPE_* constants.
/**
     * Returns one of the constants starting with
     * {@code DATATYPE_}, indicating the format and
     * interpretation of the value of the given attribute within the
     * named element.  If {@code getAttributeValueType} returns
     * {@code 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 {@code DATATYPE_*} constants.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if {@code attrName} is
     * {@code 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. 
Params:
  • elementName – the name of the element being queried.
  • attrName – the name of the attribute being queried.
Throws:
Returns:true if the attribute must be present.
/**
     * Returns {@code 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 {@code true} if the attribute must be present.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if {@code attrName} is
     * {@code 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 explicitly present within the named element, as a String, or null if no default value is available. 
Params:
  • elementName – the name of the element being queried.
  • attrName – the name of the attribute being queried.
Throws:
Returns:a String containing the default value, or null.
/**
     * Returns the default value of the named attribute, if it is not
     * explicitly present within the named element, as a
     * {@code String}, or {@code 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 {@code String} containing the default value, or
     * {@code null}.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if {@code attrName} is
     * {@code null} or is not a legal attribute name for this
     * element.
     */
    String getAttributeDefaultValue(String elementName, String attrName);

    
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. 
Params:
  • elementName – the name of the element being queried.
  • attrName – the name of the attribute being queried.
Throws:
Returns:an array of Strings.
/**
     * Returns an array of {@code String}s containing the legal
     * enumerated values for the given attribute within the named
     * element.  This method should only be called if
     * {@code getAttributeValueType} returns
     * {@code VALUE_ENUMERATION}.
     *
     * @param elementName the name of the element being queried.
     * @param attrName the name of the attribute being queried.
     *
     * @return an array of {@code String}s.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if {@code attrName} is
     * {@code 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_*. 
Params:
  • elementName – the name of the element being queried.
  • attrName – the name of the attribute being queried.
Throws:
Returns:a String containing the smallest legal value for the attribute.
/**
     * Returns the minimum legal value for the attribute.  Whether
     * this value is inclusive or exclusive may be determined by the
     * value of {@code getAttributeValueType}.  The value is
     * returned as a {@code String}; its interpretation is
     * dependent on the value of {@code getAttributeDataType}.
     * This method should only be called if
     * {@code getAttributeValueType} returns
     * {@code VALUE_RANGE_*}.
     *
     * @param elementName the name of the element being queried.
     * @param attrName the name of the attribute being queried.
     *
     * @return a {@code String} containing the smallest legal
     * value for the attribute.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if {@code attrName} is
     * {@code 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_*. 
Params:
  • elementName – the name of the element being queried, as a String.
  • attrName – the name of the attribute being queried.
Throws:
Returns:a String containing the largest legal value for the attribute.
/**
     * Returns the maximum legal value for the attribute.  Whether
     * this value is inclusive or exclusive may be determined by the
     * value of {@code getAttributeValueType}.  The value is
     * returned as a {@code String}; its interpretation is
     * dependent on the value of {@code getAttributeDataType}.
     * This method should only be called if
     * {@code getAttributeValueType} returns
     * {@code VALUE_RANGE_*}.
     *
     * @param elementName the name of the element being queried, as a
     * {@code String}.
     * @param attrName the name of the attribute being queried.
     *
     * @return a {@code String} containing the largest legal
     * value for the attribute.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if {@code attrName} is
     * {@code 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. 
Params:
  • elementName – the name of the element being queried.
  • attrName – the name of the attribute being queried.
Throws:
Returns:the smallest legal number of list items for the
attribute.
/**
     * Returns the minimum number of list items that may be used to
     * define this attribute.  The attribute itself is defined as a
     * {@code String} containing multiple whitespace-separated
     * items.  This method should only be called if
     * {@code getAttributeValueType} returns
     * {@code 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 {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if {@code attrName} is
     * {@code 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. 
Params:
  • elementName – the name of the element being queried.
  • attrName – the name of the attribute being queried.
Throws:
Returns:the largest legal number of list items for the
attribute.
/**
     * Returns the maximum number of list items that may be used to
     * define this attribute.  A value of
     * {@code Integer.MAX_VALUE} may be used to specify that
     * there is no upper bound.  The attribute itself is defined as a
     * {@code String} containing multiple whitespace-separated
     * items.  This method should only be called if
     * {@code getAttributeValueType} returns
     * {@code 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 {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if {@code attrName} is
     * {@code 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 description will be localized for the supplied Locale if possible. 
 If locale is null, the current default Locale returned by Locale.getLocale will be used. 
Params:
  • elementName – the name of the element.
  • attrName – the name of the attribute.
  • locale – the Locale for which localization will be attempted.
Throws:
Returns:the attribute description.
/**
     * Returns a {@code String} containing a description of the
     * named attribute, or {@code null}.  The description will be
     * localized for the supplied {@code Locale} if possible.
     *
     * <p> If {@code locale} is {@code null}, the current
     * default {@code Locale} returned by {@code Locale.getLocale}
     * will be used.
     *
     * @param elementName the name of the element.
     * @param attrName the name of the attribute.
     * @param locale the {@code Locale} for which localization
     * will be attempted.
     *
     * @return the attribute description.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null}, or is not a legal element name for this format.
     * @exception IllegalArgumentException if {@code attrName} is
     * {@code 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. 
Params:
  • elementName – the name of the element being queried.
Throws:
See Also:
Returns:one of the VALUE_* constants.
/**
     * Returns one of the enumerated values starting with
     * {@code VALUE_}, indicating the type of values
     * (enumeration, range, or array) that are allowed for the
     * {@code Object} reference.  If no object value can be
     * stored within the given element, the result of this method will
     * be {@code VALUE_NONE}.
     *
     * <p> {@code Object} references whose legal values are
     * defined as a range must implement the {@code Comparable}
     * interface.
     *
     * @param elementName the name of the element being queried.
     *
     * @return one of the {@code VALUE_*} constants.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code 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 ints, this method would return int.class). 
 Object references whose legal values are defined as a range must implement the Comparable interface. 
Params:
  • elementName – the name of the element being queried.
Throws:
Returns:a Class object.
/**
     * Returns the {@code Class} type of the {@code Object}
     * reference stored within the element.  If this element may not
     * contain an {@code Object} reference, an
     * {@code IllegalArgumentException} will be thrown.  If the
     * class type is an array, this field indicates the underlying
     * class type (<i>e.g</i>, for an array of {@code int}s, this
     * method would return {@code int.class}).
     *
     * <p> {@code Object} references whose legal values are
     * defined as a range must implement the {@code Comparable}
     * interface.
     *
     * @param elementName the name of the element being queried.
     *
     * @return a {@code Class} object.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if the named element cannot
     * contain an object value (<i>i.e.</i>, if
     * {@code getObjectValueType(elementName) == VALUE_NONE}).
     */
    Class<?> getObjectClass(String elementName);

    
Returns an Objects containing the default value for the Object reference within the named element. 
Params:
  • elementName – the name of the element being queried.
Throws:
Returns:an Object.
/**
     * Returns an {@code Object}s containing the default
     * value for the {@code Object} reference within
     * the named element.
     *
     * @param elementName the name of the element being queried.
     *
     * @return an {@code Object}.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if the named element cannot
     * contain an object value (<i>i.e.</i>, if
     * {@code getObjectValueType(elementName) == VALUE_NONE}).
     */
    Object getObjectDefaultValue(String elementName);

    
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 enumerated 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). 
Params:
  • elementName – the name of the element being queried.
Throws:
Returns:an array of Objects.
/**
     * Returns an array of {@code Object}s containing the legal
     * enumerated values for the {@code Object} reference within
     * the named element.  This method should only be called if
     * {@code getObjectValueType} returns
     * {@code VALUE_ENUMERATION}.
     *
     * <p> The {@code Object} associated with a node that accepts
     * enumerated values must be equal to one of the values returned by
     * this method, as defined by the {@code ==} operator (as
     * opposed to the {@code Object.equals} method).
     *
     * @param elementName the name of the element being queried.
     *
     * @return an array of {@code Object}s.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if the named element cannot
     * contain an object value (<i>i.e.</i>, if
     * {@code getObjectValueType(elementName) == VALUE_NONE}).
     * @exception IllegalArgumentException if the {@code 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. 
Params:
  • elementName – the name of the element being queried.
Throws:
Returns:the smallest legal value for the attribute.
/**
     * Returns the minimum legal value for the {@code Object}
     * reference within the named element.  Whether this value is
     * inclusive or exclusive may be determined by the value of
     * {@code getObjectValueType}.  This method should only be
     * called if {@code getObjectValueType} returns one of the
     * constants starting with {@code VALUE_RANGE}.
     *
     * @param elementName the name of the element being queried.
     *
     * @return the smallest legal value for the attribute.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if the named element cannot
     * contain an object value (<i>i.e.</i>, if
     * {@code getObjectValueType(elementName) == VALUE_NONE}).
     * @exception IllegalArgumentException if the {@code 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. 
Params:
  • elementName – the name of the element being queried.
Throws:
Returns:the smallest legal value for the attribute.
/**
     * Returns the maximum legal value for the {@code Object}
     * reference within the named element.  Whether this value is
     * inclusive or exclusive may be determined by the value of
     * {@code getObjectValueType}.  This method should only be
     * called if {@code getObjectValueType} returns one of the
     * constants starting with {@code VALUE_RANGE}.
     *
     * @return the smallest legal value for the attribute.
     *
     * @param elementName the name of the element being queried.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if the named element cannot
     * contain an object value (<i>i.e.</i>, if
     * {@code getObjectValueType(elementName) == VALUE_NONE}).
     * @exception IllegalArgumentException if the {@code 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. 
Params:
  • elementName – the name of the element being queried.
Throws:
Returns:the smallest valid array length for the Object reference.
/**
     * Returns the minimum number of array elements that may be used
     * to define the {@code Object} reference within the named
     * element.  This method should only be called if
     * {@code getObjectValueType} returns
     * {@code VALUE_LIST}.
     *
     * @param elementName the name of the element being queried.
     *
     * @return the smallest valid array length for the
     * {@code Object} reference.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if the named element cannot
     * contain an object value (<i>i.e.</i>, if
     * {@code getObjectValueType(elementName) == VALUE_NONE}).
     * @exception IllegalArgumentException if the {@code 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. 
Params:
  • elementName – the name of the element being queried.
Throws:
Returns:the largest valid array length for the Object reference.
/**
     * Returns the maximum number of array elements that may be used
     * to define the {@code Object} reference within the named
     * element.  A value of {@code Integer.MAX_VALUE} may be used
     * to specify that there is no upper bound.  This method should
     * only be called if {@code getObjectValueType} returns
     * {@code VALUE_LIST}.
     *
     * @param elementName the name of the element being queried.
     *
     * @return the largest valid array length for the
     * {@code Object} reference.
     *
     * @exception IllegalArgumentException if {@code elementName}
     * is {@code null} or is not a legal element name for this
     * format.
     * @exception IllegalArgumentException if the named element cannot
     * contain an object value (<i>i.e.</i>, if
     * {@code getObjectValueType(elementName) == VALUE_NONE}).
     * @exception IllegalArgumentException if the {@code Object} is not
     * an array.
     */
    int getObjectArrayMaxLength(String elementName);
}