net.sf.saxon.ma.zeno

Class ZenoSequence

java.lang.Object

net.sf.saxon.ma.zeno.ZenoSequence

All Implemented Interfaces:

GroundedValue, Sequence

public class ZenoSequence
extends java.lang.Object
implements GroundedValue

An immutable XDM sequence implemented as a ZenoChain.

This sequence implementation

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ZenoSequence.ZenoSequenceIterator A SequenceIterator over a ZenoSequence

Constructor Summary

Constructors

Constructor and Description
ZenoSequence() Construct an empty ZenoSequence
ZenoSequence(ZenoChain<Item> chain) Constructor to create a ZenoSequence that wraps a supplied ZenoChain

Method Summary

Modifier and Type	Method and Description
ZenoSequence	append(Item item) Append a single item to the end of the sequence
ZenoSequence	appendSequence(GroundedValue items) Append a sequence of item to the end of the sequence
static ZenoSequence	fromList(java.util.List<Item> items) Construct a ZenoSequence from a list of items
int	getLength() Get the length of the sequence
java.lang.String	getStringValue() Get a string representation of the sequence, consisting of the space-separated concatenation of the string representation of the items in the sequence
UnicodeString	getUnicodeStringValue() Get a string representation of the sequence, consisting of the space-separated concatenation of the string representation of the items in the sequence
Item	head() Get the first item in the sequence
Item	itemAt(int n) Get the item at a given position in the sequence
SequenceIterator	iterate() Get an iterator over the items in the sequence
static ZenoSequence	join(java.util.List<GroundedValue> segments) Create a ZenoSequence by concatenating a number of sequences
GroundedValue	subsequence(int start, int length) Get a subsequence of the value

Methods inherited from class java.lang.Object

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

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

asIterable, concatenate, containsNode, effectiveBooleanValue, materialize, reduce, toShortString

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

makeRepeatable

Constructor Detail

ZenoSequence

public ZenoSequence()

Construct an empty ZenoSequence

ZenoSequence

public ZenoSequence(ZenoChain<Item> chain)

Constructor to create a ZenoSequence that wraps a supplied ZenoChain

Parameters:

chain - the supplied ZenoChain

Method Detail

fromList

public static ZenoSequence fromList(java.util.List<Item> items)

Construct a ZenoSequence from a list of items

Parameters:

items - the items to be included

Returns:

the new ZenoSequence

iterate

public SequenceIterator iterate()

Get an iterator over the items in the sequence

Specified by:

iterate in interface GroundedValue

Specified by:

iterate in interface Sequence

Returns:

an iterator over the items in the sequence

itemAt

public Item itemAt(int n)

Get the item at a given position in the sequence

Specified by:

itemAt in interface GroundedValue

Parameters:

n - the index of the required item, with zero (0) representing the first item in the sequence

Returns:

the item at the given position, or null if the position is out of range

head

public Item head()

Get the first item in the sequence

Specified by:

head in interface GroundedValue

Specified by:

head in interface Sequence

Returns:

the first item in the sequence, or null if the sequence is empty

subsequence

public GroundedValue subsequence(int start,
                                 int length)

Get a subsequence of the value

Specified by:

subsequence in interface GroundedValue

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 length goes off the end of the sequence, the result returns items up to the end of the sequence

Returns:

the required subsequence.

getLength

public int getLength()

Get the length of the sequence

Specified by:

getLength in interface GroundedValue

Returns:

the number of items in the sequence

getUnicodeStringValue

public UnicodeString getUnicodeStringValue()
                                    throws XPathException

Get a string representation of the sequence, consisting of the space-separated concatenation of the string representation of the items in the sequence

Specified by:

getUnicodeStringValue in interface GroundedValue

Returns:

a Unicode string containing the result of getting the string value of each item in the sequence, space-separated

Throws:

XPathException - if there is an item in the sequence with no string value, for example a map

getStringValue

public java.lang.String getStringValue()
                                throws XPathException

Get a string representation of the sequence, consisting of the space-separated concatenation of the string representation of the items in the sequence

Specified by:

getStringValue in interface GroundedValue

Returns:

a Unicode string containing the result of getting the string value of each item in the sequence, space-separated

Throws:

XPathException - if there is an item in the sequence with no string value, for example a map

append

public ZenoSequence append(Item item)

Append a single item to the end of the sequence

Parameters:

item - the item to be appended

Returns:

a new sequence containing the additional item. The original sequence is unchanged.

appendSequence

public ZenoSequence appendSequence(GroundedValue items)

Append a sequence of item to the end of the sequence

Parameters:

items - the items to be appended

Returns:

a new sequence containing the additional items. The original sequence is unchanged.

join

public static ZenoSequence join(java.util.List<GroundedValue> segments)

Create a ZenoSequence by concatenating a number of sequences

Parameters:

segments - the sequences to be concatenated

Returns:

the result of the concatenation