## net.sf.saxon.value
Class EmptySequence

    java.lang.Object
      net.sf.saxon.value.Value
          net.sf.saxon.value.EmptySequence

All Implemented Interfaces:
  Serializable, Comparable, SequenceIterable, ValueRepresentation

    public final class EmptySequence

extends Value

An EmptySequence object represents a sequence containing no members.

See Also:
  Serialized Form

Field Summary

Fields inherited from class net.sf.saxon.value.Value
`EMPTY_CLASS_ARRAY, INDETERMINATE_ORDERING`

Fields inherited from interface net.sf.saxon.om.ValueRepresentation
`EMPTY_VALUE_ARRAY`

Method Summary
`Item` `asItem()` Return the value in the form of an Item
`boolean` `effectiveBooleanValue()` Get the effective boolean value - always false
`boolean` `equals(Object other)` Is this expression the same as another expression?
`int` `getCardinality()` Determine the static cardinality
`static EmptySequence` `getInstance()` Get the implicit instance of this class
`ItemType` `getItemType(TypeHierarchy th)` Determine the item type
`int` `getLength()` Get the length of the sequence
`int` `hashCode()` Return a hash code to support the equals() function
`boolean` `isMultiValued()` Determine whether the value is multivalued, that is, whether it is a sequence that potentially contains more than one item
`SequenceIterator` `iterate()` Return an iteration over the sequence

Methods inherited from class net.sf.saxon.value.Value
`asItem, asIterator, asValue, checkPermittedContents, compareTo, convert, convertJavaObjectToXPath, convertToJava, fromItem, getCanonicalLexicalRepresentation, getIterator, getSchemaComparable, getStringValue, getStringValueCS, itemAt, iterate, makeQNameValue, process, reduce, stringToNumber, toString`

Methods inherited from class java.lang.Object
`getClass, notify, notifyAll, wait, wait, wait`

Method Detail

### getInstance

    public static EmptySequence getInstance()

  Get the implicit instance of this class

### isMultiValued

    public boolean isMultiValued()

  Determine whether the value is multivalued, that is, whether it is a sequence that potentially contains more than one item

  Specified by:
    `isMultiValued` in class `Value`
  Returns:
    true if the value might contain more than one item, false if it definitely contains zero or one items

### iterate

    public SequenceIterator iterate()

  Return an iteration over the sequence

  Specified by:
    `iterate` in class `Value`
  Returns:
    an iterator over the sequence of items

### asItem

    public Item asItem()

  Return the value in the form of an Item

  Overrides:
    `asItem` in class `Value`
  Returns:
    the value in the form of an Item

### getItemType

    public ItemType getItemType(TypeHierarchy th)

  Determine the item type

  Overrides:
    `getItemType` in class `Value`
  Parameters:
    `th` -
  Returns:
    for the default implementation: AnyItemType (not known)

### getCardinality

    public int getCardinality()

  Determine the static cardinality

  Overrides:
    `getCardinality` in class `Value`

### getLength

    public final int getLength()

  Get the length of the sequence

  Overrides:
    `getLength` in class `Value`
  Returns:
    always 0 for an empty sequence

### equals

    public boolean equals(Object other)

  Is this expression the same as another expression?

  Overrides:
    `equals` in class `Value`
  Throws:
    `ClassCastException` - if the values are not comparable

### hashCode

    public int hashCode()

  Description copied from class: `Value`
  Return a hash code to support the equals() function

  Overrides:
    `hashCode` in class `Value`

### effectiveBooleanValue

    public boolean effectiveBooleanValue()

  Get the effective boolean value - always false

  Overrides:
    `effectiveBooleanValue` in class `Value`
  Returns:
    the effective boolean value

Copyright (C) Michael H. Kay. All rights reserved.