net.sf.saxon.value
Class AtomicUserDefinedValue

java.lang.Object
  net.sf.saxon.value.Value
      net.sf.saxon.value.AtomicValue
          net.sf.saxon.value.AtomicUserDefinedValue

All Implemented Interfaces:

Serializable, Expression, Item

public class AtomicUserDefinedValue
extends AtomicValue
implements Item

A AtomicUserDefinedValue is an atomic value of a user-defined type

See Also:

Serialized Form

Field Summary

(package private) AtomicValue	primitiveValue
(package private) AtomicType	typeLabel

Method Summary

int	conversionPreference(Class required) Get conversion preference for this value to a Java class.
AtomicValue	convert(int requiredType) Convert the value to a given type.
Object	convertToJava(Class target) Convert to Java object (for passing to external functions)
void	display(int level, NamePool pool) Diagnostic print of expression structure.
boolean	effectiveBooleanValue(XPathContext context) Get the effective boolean value of the value
boolean	equals(Object obj)
Item	evaluateItem(XPathContext context) Evaluate the value (this simply returns the value unchanged)
ItemType	getItemType() Determine the data type of the expression, if possible.
AtomicValue	getPrimitiveValue() Get the primitive value (the value in the value space)
String	getStringValue() Evaluate as a string
int	hashCode()
static AtomicUserDefinedValue	makeValue(AtomicValue primValue, AtomicType type, boolean throwError) Create a value of a user-defined atomic type

Methods inherited from class net.sf.saxon.value.AtomicValue

convert, convert, evaluateAsString, getCardinality, getComponent, getTypedValue, iterate

Methods inherited from class net.sf.saxon.value.Value

analyze, asItem, asValue, collapseWhitespace, getDependencies, getSpecialProperties, getSubExpressions, inverse, normalizeWhitespace, promote, simplify, stringToInteger, stringToNumber, trimWhitespace

Methods inherited from class java.lang.Object

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

Methods inherited from interface net.sf.saxon.om.Item

getTypedValue

Field Detail

primitiveValue

AtomicValue primitiveValue

typeLabel

AtomicType typeLabel

Method Detail

makeValue

public static AtomicUserDefinedValue makeValue(AtomicValue primValue,
                                               AtomicType type,
                                               boolean throwError)
                                        throws XPathException

Create a value of a user-defined atomic type

Parameters:

primValue - the value in the value space of the primitive type

type - the required atomic type

throwError - true if an exception is to be thrown when the value is invalid (if false, the method returns null instead)

Throws:

XPathException - if the value is invalid

getPrimitiveValue

public AtomicValue getPrimitiveValue()

Get the primitive value (the value in the value space)

Overrides:

getPrimitiveValue in class AtomicValue

convert

public AtomicValue convert(int requiredType)
                    throws XPathException

Convert the value to a given type. The result of the conversion will be an atomic value of the required type.

Specified by:

convert in class AtomicValue

Parameters:

requiredType - type code of the required atomic type

Returns:

the result of the conversion, if conversion was possible. This will always be an instance of the class corresponding to the type of value requested

Throws:

XPathException - if conversion is not allowed for this required type, or if the particular value cannot be converted

evaluateItem

public Item evaluateItem(XPathContext context)
                  throws XPathException

Evaluate the value (this simply returns the value unchanged)

Specified by:

evaluateItem in interface Expression

Overrides:

evaluateItem in class AtomicValue

Parameters:

context - the evaluation context (not used in this implementation)

Returns:

the value, unchanged

Throws:

XPathException

getStringValue

public String getStringValue()
                      throws XPathException

Evaluate as a string

Specified by:

getStringValue in interface Item

Returns:

the string value of the item

Throws:

XPathException - if the string value cannot be obtained. Some items have no string value, e.g. a QName

effectiveBooleanValue

public boolean effectiveBooleanValue(XPathContext context)

Get the effective boolean value of the value

Specified by:

effectiveBooleanValue in interface Expression

Overrides:

effectiveBooleanValue in class AtomicValue

Parameters:

context - the evaluation context (not used in this implementation)

Returns:

true, unless the value is boolean false, numeric zero, or zero-length string

hashCode

public int hashCode()

Overrides:

hashCode in class Object

convertToJava

public Object convertToJava(Class target)
                     throws XPathException

Description copied from class: AtomicValue

Convert to Java object (for passing to external functions)

Overrides:

convertToJava in class AtomicValue

Parameters:

target - The class required by the external function

Returns:

an object of the target class

Throws:

XPathException

conversionPreference

public int conversionPreference(Class required)

Description copied from class: AtomicValue

Get conversion preference for this value to a Java class. A low result indicates higher preference. This method is overridden in subclasses, but it contains common functionality to supply a scalar value to a method expecting a list or iterator.

Overrides:

conversionPreference in class AtomicValue

getItemType

public ItemType getItemType()

Description copied from interface: Expression

Determine the data type of the expression, if possible. All expression return sequences, in general; this method determines the type of the items within the sequence, assuming that (a) this is known in advance, and (b) it is the same for all items in the sequence.

This method should always return a result, though it may be the best approximation that is available at the time.

Specified by:

getItemType in interface Expression

Returns:

a value such as Type.STRING, Type.BOOLEAN, Type.NUMBER, Type.NODE, or Type.ITEM (meaning not known at compile time)

display

public void display(int level,
                    NamePool pool)

Description copied from interface: Expression

Diagnostic print of expression structure. The expression is written to the System.err output stream

Specified by:

display in interface Expression

Parameters:

level - indentation level for this expression

equals

public boolean equals(Object obj)

Overrides:

equals in class Object