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## 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
`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
`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
`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 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, boolean required, Object defaultValue)` Allows an `Object` reference of a given class type to be stored in nodes implementing the named element.
`protected void` | `addObjectValue(String elementName, Class classType, boolean required, Object defaultValue, List enumeratedValues)` Allows an `Object` reference of a given class type to be stored in nodes implementing the named element.
`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 void` | `addObjectValue(String elementName, Class classType, Object defaultValue, Comparable minValue, Comparable 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 `String`s 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 `String`s 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 `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.
`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 `Object`s containing the default value for the `Object` reference within the named element.
`Object[]` | `getObjectEnumerations(String elementName)` Returns an array of `Object`s 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 `ResourceBundle`s.
`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 `ResourceBundle`s 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`.

### 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`.

Method Detail

### setResourceBaseName

    protected void setResourceBaseName(String resourceBaseName)

  Sets a new base name for locating `ResourceBundle`s 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 `ResourceBundle`s.

  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.

### 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.

### 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.

### 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.

### addAttribute

    protected void addAttribute(String elementName,
                                String attrName,
                                int dataType,
                                boolean required,
                                String defaultValue,
                                List 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 `String`s containing the legal values for the attribute.
  Throws:
    `IllegalArgumentException` - if `elementName` is `null`, or is not a legal element name for this format.

### 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.

### 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.

### 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.

### 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 void addObjectValue(String elementName,
                                  Class classType,
                                  boolean required,
                                  Object 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 void addObjectValue(String elementName,
                                  Class classType,
                                  boolean required,
                                  Object defaultValue,
                                  List 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 `Object`s containing the legal values for the object reference.
  Throws:
    `IllegalArgumentException` - if `elementName` is `null`, or is not a legal element name for this format.

### addObjectValue

    protected void addObjectValue(String elementName,
                                  Class classType,
                                  Object defaultValue,
                                  Comparable minValue,
                                  Comparable 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 `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.

  Specified by:
    `getChildNames` in interface `IIOMetadataFormat`
  Parameters:
    `elementName` - the name of the element being queried.
  Returns:
    an array of `String`s, or null.

### getAttributeNames

    public String[] getAttributeNames(String elementName)

  Description copied from interface: `IIOMetadataFormat`
  Returns an array of `String`s 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 `String`s.

### 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 `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`.

  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 `String`s.

### 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 attribite 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.
  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 `int`s, 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 `Object`s 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 `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).

  Specified by:
    `getObjectEnumerations` in interface `IIOMetadataFormat`
  Parameters:
    `elementName` - the name of the element being queried.
  Returns:
    an array of `Object`s.

### 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.

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