# Class IIOMetadataFormatImpl

java.lang.Object
javax.imageio.metadata.IIOMetadataFormatImpl

All Implemented Interfaces:
  `IIOMetadataFormat`

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

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

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

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

See Also:
  - `ResourceBundle.getBundle(String,Locale)`

## Field Summary

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

### Fields declared in interface IIOMetadataFormat

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

## Constructor Summary

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

## Method Summary

Modifier and Type
Method
Description
`protected void`
`addAttribute(String elementName, String attrName, int dataType, boolean required, int listMinLength, int listMaxLength)`
Adds a new attribute to a previously defined element that will be defined by a list of values.
`protected void`
`addAttribute(String elementName, String attrName, int dataType, boolean required, String defaultValue)`
Adds a new attribute to a previously defined element that may be set to an arbitrary value.
`protected void`
`addAttribute(String elementName, String attrName, int dataType, boolean required, String defaultValue, 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`
`addAttribute(String elementName, String attrName, int dataType, boolean required, String defaultValue, List<String> enumeratedValues)`
Adds a new attribute to a previously defined element that will be defined by a set of enumerated values.
`protected void`
`addBooleanAttribute(String elementName, String attrName, boolean hasDefaultValue, boolean defaultValue)`
Adds a new attribute to a previously defined element that will be defined by the enumerated values `TRUE` and `FALSE`, with a datatype of `DATATYPE_BOOLEAN`.
`protected void`
`addChildElement(String elementName, String parentName)`
Adds an existing element to the list of legal children for a given parent node type.
`protected void`
`addElement(String elementName, String parentName, int childPolicy)`
Adds a new element type to this metadata document format with a child policy other than `CHILD_POLICY_REPEAT`.
`protected void`
`addElement(String elementName, String parentName, int minChildren, int maxChildren)`
Adds a new element type to this metadata document format with a child policy of `CHILD_POLICY_REPEAT`.
`protected void`
`addObjectValue(String elementName, Class<?> classType, int arrayMinLength, int arrayMaxLength)`
Allows an `Object` reference of a given class type to be stored in nodes implementing the named element.
`protected <T> void`
`addObjectValue(String elementName, Class<T> classType, boolean required, T defaultValue)`
Allows an `Object` reference of a given class type to be stored in nodes implementing the named element.
`protected <T> void`
`addObjectValue(String elementName, Class<T> classType, boolean required, T defaultValue, List<? extends T> enumeratedValues)`
Allows an `Object` reference of a given class type to be stored in nodes implementing the named element.
`protected <T extends Object & Comparable<? super T>>
void`
`addObjectValue(String elementName, Class<T> classType, T defaultValue, Comparable<? super T> minValue, Comparable<? super T> maxValue, boolean minInclusive, boolean maxInclusive)`
Allows an `Object` reference of a given class type to be stored in nodes implementing the named element.
`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 the named element.
`String`
`getAttributeDefaultValue(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.
`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 declared in class Object

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

### Methods declared in interface IIOMetadataFormat

`canNodeAppear`

## Field Details

### standardMetadataFormatName

public static final String standardMetadataFormatName
A `String` constant containing the standard format name, `"javax_imageio_1.0"`.

See Also:
  - Constant Field Values

## Constructor Details

### IIOMetadataFormatImpl

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

Parameters:
  `rootName` - the name of the root element.
  `childPolicy` - one of the `CHILD_POLICY_*` constants, other than `CHILD_POLICY_REPEAT`.
Throws:
  `IllegalArgumentException` - if `rootName` is `null`.
  `IllegalArgumentException` - if `childPolicy` is not one of the predefined constants.

### IIOMetadataFormatImpl

public IIOMetadataFormatImpl(String rootName, int minChildren, int maxChildren)
Constructs a blank `IIOMetadataFormatImpl` instance, with a given root element name and a child policy of `CHILD_POLICY_REPEAT`. Additional elements, and their attributes and `Object` reference information may be added using the various `add` methods.

Parameters:
  `rootName` - the name of the root element.
  `minChildren` - the minimum number of children of the node.
  `maxChildren` - the maximum number of children of the node.
Throws:
  `IllegalArgumentException` - if `rootName` is `null`.
  `IllegalArgumentException` - if `minChildren` is negative or larger than `maxChildren`.

## Method Details

### 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` containing 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(String)`

### addElement

protected void addElement(String elementName, String parentName, int childPolicy)
Adds a new element type to this metadata document format with a child policy other than `CHILD_POLICY_REPEAT`.

Parameters:
  `elementName` - the name of the new element.
  `parentName` - the name of the element that will be the parent of the new element.
  `childPolicy` - one of the `CHILD_POLICY_*` constants, other than `CHILD_POLICY_REPEAT`, indicating the child policy of the new element.
Throws:
  `IllegalArgumentException` - if `parentName` is `null`, or is not a legal element name for this format.
  `IllegalArgumentException` - if `childPolicy` is not one of the predefined constants.

### addElement

protected void addElement(String elementName, String parentName, int minChildren, int maxChildren)
Adds a new element type to this metadata document format with a child policy of `CHILD_POLICY_REPEAT`.

Parameters:
  `elementName` - the name of the new element.
  `parentName` - the name of the element that will be the parent of the new element.
  `minChildren` - the minimum number of children of the node.
  `maxChildren` - the maximum number of children of the node.
Throws:
  `IllegalArgumentException` - if `parentName` is `null`, or is not a legal element name for this format.
  `IllegalArgumentException` - if `minChildren` is negative or larger than `maxChildren`.

### addChildElement

protected void addChildElement(String elementName, String parentName)
Adds an existing element to the list of legal children for a given parent node type.

Parameters:
  `elementName` - the name of the element to be added as a child.
  `parentName` - the name of the element that will be the new parent of the element.
Throws:
  `IllegalArgumentException` - if `elementName` is `null`, or is not a legal element name for this format.
  `IllegalArgumentException` - if `parentName` is `null`, or is not a legal element name for this format.

### removeElement

protected void removeElement(String elementName)
Removes an element from the format. If no element with the given name was present, nothing happens and no exception is thrown.

Parameters:
  `elementName` - the name of the element to be removed.

### addAttribute

protected void addAttribute(String elementName, String attrName, int dataType, boolean required, String defaultValue)
Adds a new attribute to a previously defined element that may be set to an arbitrary value.

Parameters:
  `elementName` - the name of the element.
  `attrName` - the name of the attribute being added.
  `dataType` - the data type (string format) of the attribute, one of the `DATATYPE_*` constants.
  `required` - `true` if the attribute must be present.
  `defaultValue` - the default value for the attribute, or `null`.
Throws:
  `IllegalArgumentException` - if `elementName` is `null`, or is not a legal element name for this format.
  `IllegalArgumentException` - if `attrName` is `null`.
  `IllegalArgumentException` - if `dataType` is not one of the predefined constants.

### addAttribute

protected void addAttribute(String elementName, String attrName, int dataType, boolean required, String defaultValue, List<String> enumeratedValues)
Adds a new attribute to a previously defined element that will be defined by a set of enumerated values.

Parameters:
  `elementName` - the name of the element.
  `attrName` - the name of the attribute being added.
  `dataType` - the data type (string format) of the attribute, one of the `DATATYPE_*` constants.
  `required` - `true` if the attribute must be present.
  `defaultValue` - the default value for the attribute, or `null`.
  `enumeratedValues` - a `List` of `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.
  `IllegalArgumentException` - if `attrName` is `null`.
  `IllegalArgumentException` - if `dataType` is not one of the predefined constants.
  `IllegalArgumentException` - if `enumeratedValues` is `null`.
  `IllegalArgumentException` - if `enumeratedValues` does not contain at least one entry.
  `IllegalArgumentException` - if `enumeratedValues` contains an element that is not a `String` or is `null`.

### addAttribute

protected void addAttribute(String elementName, String attrName, int dataType, boolean required, String defaultValue, String minValue, String maxValue, boolean minInclusive, boolean maxInclusive)
Adds a new attribute to a previously defined element that will be defined by a range of values.

Parameters:
  `elementName` - the name of the element.
  `attrName` - the name of the attribute being added.
  `dataType` - the data type (string format) of the attribute, one of the `DATATYPE_*` constants.
  `required` - `true` if the attribute must be present.
  `defaultValue` - the default value for the attribute, or `null`.
  `minValue` - the smallest (inclusive or exclusive depending on the value of `minInclusive`) legal value for the attribute, as a `String`.
  `maxValue` - the largest (inclusive or exclusive depending on the value of `minInclusive`) legal value for the attribute, as a `String`.
  `minInclusive` - `true` if `minValue` is inclusive.
  `maxInclusive` - `true` if `maxValue` is inclusive.
Throws:
  `IllegalArgumentException` - if `elementName` is `null`, or is not a legal element name for this format.
  `IllegalArgumentException` - if `attrName` is `null`.
  `IllegalArgumentException` - if `dataType` is not one of the predefined constants.

### addAttribute

protected void addAttribute(String elementName, String attrName, int dataType, boolean required, int listMinLength, int listMaxLength)
Adds a new attribute to a previously defined element that will be defined by a list of values.

Parameters:
  `elementName` - the name of the element.
  `attrName` - the name of the attribute being added.
  `dataType` - the data type (string format) of the attribute, one of the `DATATYPE_*` constants.
  `required` - `true` if the attribute must be present.
  `listMinLength` - the smallest legal number of list items.
  `listMaxLength` - the largest legal number of list items.
Throws:
  `IllegalArgumentException` - if `elementName` is `null`, or is not a legal element name for this format.
  `IllegalArgumentException` - if `attrName` is `null`.
  `IllegalArgumentException` - if `dataType` is not one of the predefined constants.
  `IllegalArgumentException` - if `listMinLength` is negative or larger than `listMaxLength`.

### addBooleanAttribute

protected void addBooleanAttribute(String elementName, String attrName, boolean hasDefaultValue, boolean defaultValue)
Adds a new attribute to a previously defined element that will be defined by the enumerated values `TRUE` and `FALSE`, with a datatype of `DATATYPE_BOOLEAN`.

Parameters:
  `elementName` - the name of the element.
  `attrName` - the name of the attribute being added.
  `hasDefaultValue` - `true` if a default value should be present.
  `defaultValue` - the default value for the attribute as a `boolean`, ignored if `hasDefaultValue` is `false`.
Throws:
  `IllegalArgumentException` - if `elementName` is `null`, or is not a legal element name for this format.
  `IllegalArgumentException` - if `attrName` is `null`.

### removeAttribute

protected void removeAttribute(String elementName, String attrName)
Removes an attribute from a previously defined element. If no attribute with the given name was present in the given element, nothing happens and no exception is thrown.

Parameters:
  `elementName` - the name of the element.
  `attrName` - the name of the attribute being removed.
Throws:
  `IllegalArgumentException` - if `elementName` is `null`, or is not a legal element name for this format.

### addObjectValue

protected <T> void addObjectValue(String elementName, Class<T> classType, boolean required, T defaultValue)
Allows an `Object` reference of a given class type to be stored in nodes implementing the named element. The value of the `Object` is unconstrained other than by its class type.

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

Type Parameters:
  `T` - the type of the object.
Parameters:
  `elementName` - the name of the element.
  `classType` - a `Class` variable indicating the legal class type for the object value.
  `required` - `true` if an object value must be present.
  `defaultValue` - the default value for the `Object` reference, or `null`.
Throws:
  `IllegalArgumentException` - if `elementName` is `null`, or is not a legal element name for this format.

### addObjectValue

protected <T> void addObjectValue(String elementName, Class<T> classType, boolean required, T defaultValue, List<? extends T> enumeratedValues)
Allows an `Object` reference of a given class type to be stored in nodes implementing the named element. The value of the `Object` must be one of the values given by `enumeratedValues`.

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

Type Parameters:
  `T` - the type of the object.
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.
  `IllegalArgumentException` - if `enumeratedValues` is `null`.
  `IllegalArgumentException` - if `enumeratedValues` does not contain at least one entry.
  `IllegalArgumentException` - if `enumeratedValues` contains an element that is not an instance of the class type denoted by `classType` or is `null`.

### addObjectValue

protected <T extends Object & Comparable<? super T>> void addObjectValue(String elementName, Class<T> classType, T defaultValue, Comparable<? super T> minValue, Comparable<? super T> maxValue, boolean minInclusive, boolean maxInclusive)
Allows an `Object` reference of a given class type to be stored in nodes implementing the named element. The value of the `Object` must be within the range given by `minValue` and `maxValue`. Furthermore, the class type must implement the `Comparable` interface.

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

Type Parameters:
  `T` - the type of the object.
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`.

### 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 primary.

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 description 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(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 the named 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 attribute 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 explicitly 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 description will be localized for the supplied `Locale` if possible.

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

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

Specified by:
  `getAttributeDescription` in interface `IIOMetadataFormat`
Parameters:
  `elementName` - the name of the element.
  `attrName` - the name of the attribute.
  `locale` - the `Locale` for which localization will be attempted, or `null`.
Returns:
  the attribute description.
Throws:
  `IllegalArgumentException` - if `elementName` is `null`, or is not a legal element name for this format.
  `IllegalArgumentException` - if `attrName` is `null` or is not a legal attribute name for this element.
See Also:
  - `setResourceBaseName(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 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).

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.