SequenceExtent

java.lang.Object
- net.sf.saxon.value.SequenceExtent<T>

All Implemented Interfaces:

java.lang.Iterable<T>, GroundedValue<T>, Sequence<T>

Direct Known Subclasses:

OneOrMore
```
public class SequenceExtent<T extends Item<?>>
extends java.lang.Object
implements GroundedValue<T>
```
A sequence value implemented extensionally. That is, this class represents a sequence by allocating memory to each item in the sequence.

Constructor Summary

Constructors
Constructor and Description
`SequenceExtent(java.util.List<T> list)` Construct a SequenceExtent from a List.
`SequenceExtent(SequenceExtent<T> ext, int start, int length)` Construct a SequenceExtent as a view of another SequenceExtent
`SequenceExtent(SequenceIterator<T> iter)` Construct a sequence containing all the remaining items in a SequenceIterator.
`SequenceExtent(T[] items)` Construct an sequence from an array of items.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`java.lang.Iterable<T>`	`asIterable()` Get the contents of this value in the form of a Java `Iterable`, so that it can be used in a for-each expression
`boolean`	`effectiveBooleanValue()` Get the effective boolean value
`static <T extends Item<?>> GroundedValue<T>`	`fromIterator(SequenceIterator<T> iter)` Deprecated. since 9.9: use `SequenceIterator.materialize()`
`int`	`getCardinality()` Determine the cardinality
`int`	`getLength()` Get the number of items in the sequence
`java.lang.String`	`getStringValue()` Get the string value of this sequence.
`java.lang.CharSequence`	`getStringValueCS()` Get the string value of this sequence.
`T`	`head()` Get the first item in the sequence.
`T`	`itemAt(int n)` Get the n'th item in the sequence (starting with 0 as the first item)
`ListIterator<T>`	`iterate()` Return an iterator over this sequence.
`java.util.Iterator<T>`	`iterator()` Get an iterator (a Java `Iterator`) over the items in this sequence.
`static <T extends Item<?>> GroundedValue<T>`	`makeResidue(SequenceIterator<T> iter)` Factory method to make a GroundedValue holding the remaining contents of any SequenceIterator, that is, the contents that have not yet been read
`static <T extends Item<?>> GroundedValue<T>`	`makeSequenceExtent(java.util.List<T> input)` Factory method to make a Value holding the contents of any List of items
`static <T extends Item<?>> GroundedValue<? extends T>`	`makeSequenceExtent(SequenceIterator<T> iter)` Deprecated. since 9.9: use `SequenceIterator.materialize()`
`GroundedValue<T>`	`reduce()` Reduce the sequence to its simplest form.
`UnfailingIterator<T>`	`reverseIterate()` Return an enumeration of this sequence in reverse order (used for reverse axes)
`GroundedValue<T>`	`subsequence(int start, int length)` Get a subsequence of the value
`java.lang.String`	`toString()`

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

Methods inherited from interface net.sf.saxon.om.GroundedValue
materialize, toShortString

Methods inherited from interface net.sf.saxon.om.Sequence
makeRepeatable

Methods inherited from interface java.lang.Iterable
forEach, spliterator

- Constructor Detail
  - SequenceExtent
```
public SequenceExtent(T[] items)
```
    Construct an sequence from an array of items. Note, the array of items is used as is, which means the caller must not subsequently change its contents.
    
    Parameters:
    
    items - the array of items to be included in the sequence
  - SequenceExtent
```
public SequenceExtent(SequenceExtent<T> ext,
                      int start,
                      int length)
```
    Construct a SequenceExtent as a view of another SequenceExtent
    
    Parameters:
    
    ext - The existing SequenceExtent
    
    start - zero-based offset of the first item in the existing SequenceExtent that is to be included in the new SequenceExtent
    
    length - The number of items in the new SequenceExtent
  - SequenceExtent
```
public SequenceExtent(java.util.List<T> list)
```
    Construct a SequenceExtent from a List. The members of the list must all be Items
    
    Parameters:
    
    list - the list of items to be included in the sequence
  - SequenceExtent
```
public SequenceExtent(SequenceIterator<T> iter)
               throws XPathException
```
    Construct a sequence containing all the remaining items in a SequenceIterator.
    
    Parameters:
    
    iter - The supplied sequence of items. The returned sequence will contain all items delivered by repeated calls on next() on this iterator, and the iterator will be consumed by calling the method.
    
    Throws:
    
    XPathException - if reading the items using the SequenceIterator raises an error
- Method Detail
  - makeSequenceExtent
```
public static <T extends Item<?>> GroundedValue<? extends T> makeSequenceExtent(SequenceIterator<T> iter)
                                                                         throws XPathException
```
    Deprecated. since 9.9: use SequenceIterator.materialize()
    
    Factory method to make a GroundedValue holding the contents of any SequenceIterator.
    
    Parameters:
    
    iter - a Sequence iterator that may or may not be consumed to deliver the items in the sequence. The iterator must be positioned at the start.
    
    Returns:
    
    a GroundedValue holding the items delivered by the SequenceIterator. If the sequence is empty the result will be an instance of EmptySequence. If it is of length one, the result will be an Item. In all other cases, it will be an instance of SequenceExtent.
    
    Throws:
    
    XPathException - if an error occurs processing the values from the iterator.
  - fromIterator
```
public static <T extends Item<?>> GroundedValue<T> fromIterator(SequenceIterator<T> iter)
                                                         throws XPathException
```
    Deprecated. since 9.9: use SequenceIterator.materialize()
    
    Factory method to make a GroundedValue holding the contents of any SequenceIterator.
    
    Parameters:
    
    iter - a Sequence iterator that may or may not be consumed to deliver the items in the sequence. The iterator must be positioned at the start.
    
    Returns:
    
    a GroundedValue holding the items delivered by the SequenceIterator. If the sequence is empty the result will be an instance of EmptySequence. If it is of length one, the result will be an Item. In other cases, the actual implementation class is not defined.
    This method is intended primarily for internal use. For external applications, calling SequenceIterator.materialize() is preferable, because it recognizes cases that can be optimized (notably, cases where the iterator is already backed by an array or list in memory).
    
    Throws:
    
    XPathException - if an error occurs processing the values from the iterator.
  - makeResidue
```
public static <T extends Item<?>> GroundedValue<T> makeResidue(SequenceIterator<T> iter)
                                                        throws XPathException
```
    Factory method to make a GroundedValue holding the remaining contents of any SequenceIterator, that is, the contents that have not yet been read
    
    Parameters:
    
    iter - a Sequence iterator that may or may not be consumed to deliver the items in the sequence. The iterator need not be positioned at the start.
    
    Returns:
    
    a GroundedValue holding the items delivered by the SequenceIterator. If the sequence is empty the result will be an instance of EmptySequence. If it is of length one, the result will be an Item. In all other cases, it will be an instance of SequenceExtent.
    
    Throws:
    
    XPathException - if an error occurs processing the values from the iterator.
  - makeSequenceExtent
```
public static <T extends Item<?>> GroundedValue<T> makeSequenceExtent(java.util.List<T> input)
```
    Factory method to make a Value holding the contents of any List of items
    
    Parameters:
    
    input - a List containing the items in the sequence
    
    Returns:
    
    a ValueRepresentation holding the items in the list. If the sequence is empty the result will be an instance of EmptySequence. If it is of length one, the result will be an Item. In all other cases, it will be an instance of SequenceExtent.
  - getStringValue
```
public java.lang.String getStringValue()
                                throws XPathException
```
    Description copied from interface: GroundedValue
    
    Get the string value of this sequence. The string value of an item is the result of applying the string() function. The string value of a sequence is the space-separated result of applying the string-join() function using a single space as the separator
    
    Specified by:
    
    getStringValue in interface GroundedValue<T extends Item<?>>
    
    Returns:
    
    the string value of the sequence.
    
    Throws:
    
    XPathException - if the sequence contains items that have no string value (for example, function items)
  - getStringValueCS
```
public java.lang.CharSequence getStringValueCS()
                                        throws XPathException
```
    Description copied from interface: GroundedValue
    
    Get the string value of this sequence. The string value of an item is the result of applying the string() function. The string value of a sequence is the space-separated result of applying the string-join() function using a single space as the separator
    
    Specified by:
    
    getStringValueCS in interface GroundedValue<T extends Item<?>>
    
    Returns:
    
    the string value of the sequence.
    
    Throws:
    
    XPathException - if the sequence contains items that have no string value (for example, function items)
  - head
```
public T head()
```
    Get the first item in the sequence.
    
    Specified by:
    
    head in interface GroundedValue<T extends Item<?>>
    
    Specified by:
    
    head in interface Sequence<T extends Item<?>>
    
    Returns:
    
    the first item in the sequence if there is one, or null if the sequence is empty
  - getLength
```
public int getLength()
```
    Get the number of items in the sequence
    
    Specified by:
    
    getLength in interface GroundedValue<T extends Item<?>>
    
    Returns:
    
    the number of items in the sequence
  - getCardinality
```
public int getCardinality()
```
    Determine the cardinality
    
    Returns:
    
    the cardinality of the sequence, using the constants defined in net.sf.saxon.value.Cardinality
    
    See Also:
    
    Cardinality
  - itemAt
```
public T itemAt(int n)
```
    Get the n'th item in the sequence (starting with 0 as the first item)
    
    Specified by:
    
    itemAt in interface GroundedValue<T extends Item<?>>
    
    Parameters:
    
    n - the position of the required item
    
    Returns:
    
    the n'th item in the sequence, or null if the position is out of range
  - iterate
```
public ListIterator<T> iterate()
```
    Return an iterator over this sequence.
    
    Specified by:
    
    iterate in interface GroundedValue<T extends Item<?>>
    
    Specified by:
    
    iterate in interface Sequence<T extends Item<?>>
    
    Returns:
    
    the required SequenceIterator, positioned at the start of the sequence
  - reverseIterate
```
public UnfailingIterator<T> reverseIterate()
```
    Return an enumeration of this sequence in reverse order (used for reverse axes)
    
    Returns:
    
    an AxisIterator that processes the items in reverse order
  - effectiveBooleanValue
```
public boolean effectiveBooleanValue()
                              throws XPathException
```
    Get the effective boolean value
    
    Specified by:
    
    effectiveBooleanValue in interface GroundedValue<T extends Item<?>>
    
    Returns:
    
    the effective boolean value
    
    Throws:
    
    XPathException - if the sequence has no effective boolean value (for example a sequence of two integers)
  - subsequence
```
public GroundedValue<T> subsequence(int start,
                                    int length)
```
    Get a subsequence of the value
    
    Specified by:
    
    subsequence in interface GroundedValue<T extends Item<?>>
    
    Parameters:
    
    start - 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
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object
  - reduce
```
public GroundedValue<T> reduce()
```
    Reduce the sequence to its simplest form. If the value is an empty sequence, the result will be EmptySequence.getInstance(). If the value is a single atomic value, the result will be an instance of AtomicValue. If the value is a single item of any other kind, the result will be an instance of One. Otherwise, the result will typically be unchanged.
    
    Specified by:
    
    reduce in interface GroundedValue<T extends Item<?>>
    
    Returns:
    
    the simplified sequence
  - asIterable
```
public java.lang.Iterable<T> asIterable()
```
    Get the contents of this value in the form of a Java Iterable, so that it can be used in a for-each expression
    
    Specified by:
    
    asIterable in interface GroundedValue<T extends Item<?>>
    
    Specified by:
    
    asIterable in interface Sequence<T extends Item<?>>
    
    Returns:
    
    an Iterable containing the same sequence of items
  - iterator
```
public java.util.Iterator<T> iterator()
```
    Get an iterator (a Java Iterator) over the items in this sequence.
    
    Specified by:
    
    iterator in interface java.lang.Iterable<T extends Item<?>>
    
    Specified by:
    
    iterator in interface GroundedValue<T extends Item<?>>
    
    Returns:
    
    an iterator over the items in this sequence.

Class SequenceExtent<T extends Item<?>>

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

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

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

Methods inherited from interface java.lang.Iterable

Constructor Detail

SequenceExtent

SequenceExtent

SequenceExtent

SequenceExtent

Method Detail

makeSequenceExtent

fromIterator

makeResidue

makeSequenceExtent

getStringValue

getStringValueCS

head

getLength

getCardinality

itemAt

iterate

reverseIterate

effectiveBooleanValue

subsequence

toString

reduce

asIterable

iterator