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

All Implemented Interfaces:

java.io.Serializable, SequenceIterable, GroundedValue, ValueRepresentation
```
public final class EmptySequence
extends Value
implements GroundedValue
```
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

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`Item`	`asItem()`	Return the value in the form of an Item
`boolean`	`effectiveBooleanValue()`	Get the effective boolean value - always false
`boolean`	`equals(java.lang.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()`
`Item`	`itemAt(int n)`	Get the n'th item in the sequence (starting from 0).
`SequenceIterator`	`iterate()`	Return an iteration over the sequence
`GroundedValue`	`subsequence(int min, int length)`	Get a subsequence of the value

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

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

Methods inherited from interface net.sf.saxon.om.ValueRepresentation
getStringValue, getStringValueCS

- Method Detail
  - getInstance
```
public static EmptySequence getInstance()
```
    Get the implicit instance of this class
  - 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 - the type hierarchy cache
    
    Returns:
    
    for the default implementation: AnyItemType (not known)
  - getCardinality
```
public int getCardinality()
```
    Determine the static cardinality
    
    Overrides:
    
    getCardinality in class Value
    
    Returns:
    
    the cardinality
  - 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(java.lang.Object other)
```
    Is this expression the same as another expression?
    
    Overrides:
    
    equals in class Value
    
    Throws:
    
    java.lang.ClassCastException - if the values are not comparable
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class java.lang.Object
  - effectiveBooleanValue
```
public boolean effectiveBooleanValue()
```
    Get the effective boolean value - always false
    
    Overrides:
    
    effectiveBooleanValue in class Value
    
    Returns:
    
    the effective boolean value
  - itemAt
```
public Item itemAt(int n)
```
    Get the n'th item in the sequence (starting from 0). This is defined for all Values, but its real benefits come for a sequence Value stored extensionally (or for a MemoClosure, once all the values have been read)
    
    Specified by:
    
    itemAt in interface GroundedValue
    
    Overrides:
    
    itemAt in class Value
    
    Parameters:
    
    n - position of the required item, counting from zero.
    
    Returns:
    
    the n'th item in the sequence, where the first item in the sequence is numbered zero. If n is negative or >= the length of the sequence, returns null.
  - subsequence
```
public GroundedValue subsequence(int min,
                                 int length)
```
    Get a subsequence of the value
    
    Specified by:
    
    subsequence in interface GroundedValue
    
    Parameters:
    
    min - the index of the first item to be included in the result, counting from zero. A negative value is taken as zero. If the value is beyond the end of the sequence, an empty sequence is returned
    
    length - the number of items to be included in the result. Specify Integer.MAX_VALUE to get the subsequence up to the end of the base sequence. If the value is negative, an empty sequence is returned. If the value goes off the end of the sequence, the result returns items up to the end of the sequence
    
    Returns:
    
    the required subsequence. If min is

Class EmptySequence

Field Summary

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

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

Method Summary

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

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

iterate

asItem

getItemType

getCardinality

getLength

equals

hashCode

effectiveBooleanValue

itemAt

subsequence