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 XDM sequence implemented as a ZenoChain

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ZenoSequence.ZenoSequenceIterator

Constructor Summary

Constructors

Constructor and Description
ZenoSequence()

Method Summary

Modifier and Type	Method and Description
void	append(Item item)
void	appendSequence(GroundedValue items)
static ZenoSequence	fromList(java.util.List<Item> items)
int	getLength() Get the size of the value (the number of items in the value, considered as a sequence)
java.lang.String	getStringValue() Get the string value of this sequence, as an instance of String.
UnicodeString	getUnicodeStringValue() Get the string value of this sequence, as an instance of UnicodeString.
Item	head() Get the first item of the sequence.
Item	itemAt(int n) Get the n'th item in the value, counting from zero (0)
SequenceIterator	iterate() Get an iterator over all the items in the sequence.
static ZenoSequence	join(java.util.List<GroundedValue> segments)
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()

Method Detail

fromList

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

iterate

public SequenceIterator iterate()

Description copied from interface: GroundedValue

Get an iterator over all the items in the sequence. This differs from the superclass method in not allowing an exception, either during this method call, or in the subsequent processing of the returned iterator.

Specified by:

iterate in interface GroundedValue

Specified by:

iterate in interface Sequence

Returns:

an iterator (meaning a Saxon SequenceIterator rather than a Java Iterator) over all the items in this Sequence.

itemAt

public Item itemAt(int n)

Description copied from interface: GroundedValue

Get the n'th item in the value, counting from zero (0)

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 n'th item if it exists, or null if the requested position is out of range

head

public Item head()

Description copied from interface: GroundedValue

Get the first item of the sequence. This differs from the parent interface in not allowing an exception

Specified by:

head in interface GroundedValue

Specified by:

head in interface Sequence

Returns:

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

subsequence

public GroundedValue subsequence(int start,
                                 int length)

Description copied from interface: GroundedValue

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()

Description copied from interface: GroundedValue

Get the size of the value (the number of items in the value, considered as a sequence)

Specified by:

getLength in interface GroundedValue

Returns:

the number of items in the sequence. Note that for a single item, including a map or array, the result is always 1 (one).

getUnicodeStringValue

public UnicodeString getUnicodeStringValue()
                                    throws XPathException

Description copied from interface: GroundedValue

Get the string value of this sequence, as an instance of UnicodeString. The string value of an item is the result of applying the XPath 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

The result of this method is always equivalent to the result of the GroundedValue.getStringValue() method. Use this method in preference either (a) if you need to use the value in a context where a UnicodeString is required, or (b) if the underlying value is held as a UnicodeString, or in a form that is readily converted to a UnicodeString. This is typically the case (i) when the value is a text or element node in a TinyTree, and (ii) when the value is a StringItem: that is, an atomic value of type xs:string.

Specified by:

getUnicodeStringValue in interface GroundedValue

Returns:

the string value of the sequence.

Throws:

XPathException - if the sequence contains items that have no string value (for example, function items)

getStringValue

public java.lang.String getStringValue()
                                throws XPathException

Description copied from interface: GroundedValue

Get the string value of this sequence, as an instance of String. The string value of an item is the result of applying the XPath 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.

The result of this method is always equivalent to the result of the GroundedValue.getUnicodeStringValue() method. Use this method in preference either (a) if you need to use the value in a context where a String is required, or (b) if the underlying value is held as a String, or in a form that is readily converted to a String. This is typically the case (i) when the value is an attribute node in a TinyTree, or (ii) any kind of node in a third-party tree model such as DOM.

Specified by:

getStringValue in interface GroundedValue

Returns:

the string value of the sequence.

Throws:

XPathException - if the sequence contains items that have no string value (for example, function items)

append

public void append(Item item)

appendSequence

public void appendSequence(GroundedValue items)

join

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