net.sf.saxon.ma.arrays

Class SimpleArrayItem

java.lang.Object

net.sf.saxon.ma.arrays.AbstractArrayItem

net.sf.saxon.ma.arrays.SimpleArrayItem

All Implemented Interfaces:

Callable, ArrayItem, Function, GroundedValue, Item, Sequence

public class SimpleArrayItem
extends AbstractArrayItem
implements ArrayItem

A simple implementation of XDM array items, in which the array is backed by a Java List.

Field Summary

Fields

Modifier and Type	Field and Description
static SimpleArrayItem	EMPTY_ARRAY Static constant value representing an empty array

Fields inherited from interface net.sf.saxon.ma.arrays.ArrayItem

SINGLE_ARRAY_TYPE

Constructor Summary

Constructors

Constructor and Description
SimpleArrayItem(java.util.List<GroundedValue> members) Construct an array whose members are arbitrary sequences

Method Summary

Modifier and Type	Method and Description
int	arrayLength() Get the size of the array
ArrayItem	concat(ArrayItem other) Concatenate this array with another
GroundedValue	get(int index) Get a member of the array
AnnotationList	getAnnotations() Get the function annotations (as defined in XQuery).
java.util.List<GroundedValue>	getMembers() Get a list of the members of the array
OperandRole[]	getOperandRoles() Get the roles of the arguments, for the purposes of streaming
ArrayItem	insert(int position, GroundedValue member) Insert a new member into an array
boolean	isArray() Ask whether this function item is an array
boolean	isEmpty() Ask whether the array is empty
boolean	isMap() Ask whether this function item is a map
void	makeGrounded() Ensure that all the members are grounded.
static SimpleArrayItem	makeSimpleArrayItem(SequenceIterator input) Construct an array whose members are single items
java.lang.Iterable<GroundedValue>	members() Get the list of all members of the array
ArrayItem	put(int index, GroundedValue newValue) Replace a member of the array
ArrayItem	remove(int pos) Remove a member from the array
ArrayItem	removeSeveral(IntSet positions) Remove zero or more members from the array
ArrayItem	subArray(int start, int end) Get a subarray given a start and end position
java.lang.String	toShortString() Provide a short string showing the contents of the item, suitable for use in error messages

Methods inherited from class net.sf.saxon.ma.arrays.AbstractArrayItem

atomize, call, deepEquals, effectiveBooleanValue, export, getArity, getDescription, getFunctionItemType, getFunctionName, getMemberType, getStringValue, getStringValueCS, isTrustedResultType, makeNewContext, 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.ma.arrays.ArrayItem

getGenre, getMemberType

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

argumentArray, call, deepEquals, export, getArity, getDescription, getFunctionItemType, getFunctionName, isTrustedResultType, makeNewContext

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

atomize, getLength, getStringValue, getStringValueCS, head, isStreamed, itemAt, iterate, reduce, subsequence, toGroundedValue

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

asIterable, concatenate, containsNode, effectiveBooleanValue, materialize

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

makeRepeatable

Field Detail

EMPTY_ARRAY

public static final SimpleArrayItem EMPTY_ARRAY

Static constant value representing an empty array

Constructor Detail

SimpleArrayItem

public SimpleArrayItem(java.util.List<GroundedValue> members)

Construct an array whose members are arbitrary sequences

Parameters:

members - the list of values (in general, each value is a sequence) to form the members of the array. The values must be repeatable sequences (not LazySequences); this is not checked.

Method Detail

makeSimpleArrayItem

public static SimpleArrayItem makeSimpleArrayItem(SequenceIterator input)
                                           throws XPathException

Construct an array whose members are single items

Parameters:

input - an iterator over the items to make up the array

Returns:

an array in which each member is a single item, taken from the input sequence

Throws:

XPathException - if evaluating the SequenceIterator fails

getOperandRoles

public OperandRole[] getOperandRoles()

Get the roles of the arguments, for the purposes of streaming

Specified by:

getOperandRoles in interface Function

Overrides:

getOperandRoles in class AbstractArrayItem

Returns:

an array of OperandRole objects, one for each argument

makeGrounded

public void makeGrounded()
                  throws XPathException

Ensure that all the members are grounded. The idea is that a member may initially be a reference to a lazily-evaluated sequence, but once computed, the reference will be replaced with the actual value

Throws:

XPathException

isArray

public boolean isArray()

Ask whether this function item is an array

Specified by:

isArray in interface Function

Overrides:

isArray in class AbstractArrayItem

Returns:

true (it is an array)

isMap

public boolean isMap()

Ask whether this function item is a map

Specified by:

isMap in interface Function

Overrides:

isMap in class AbstractArrayItem

Returns:

false (it is not a map)

getAnnotations

public AnnotationList getAnnotations()

Get the function annotations (as defined in XQuery). Returns an empty list if there are no function annotations.

Specified by:

getAnnotations in interface Function

Overrides:

getAnnotations in class AbstractArrayItem

Returns:

the function annotations

get

public GroundedValue get(int index)

Get a member of the array

Specified by:

get in interface ArrayItem

Parameters:

index - the position of the member to retrieve (zero-based)

Returns:

the value at the given position.

Throws:

java.lang.IndexOutOfBoundsException - if the index is out of range

put

public ArrayItem put(int index,
                     GroundedValue newValue)

Replace a member of the array

Specified by:

put in interface ArrayItem

Parameters:

index - the position of the member to replace (zero-based)

newValue - the replacement value

Returns:

the value at the given position.

Throws:

java.lang.IndexOutOfBoundsException - if the index is out of range

arrayLength

public int arrayLength()

Get the size of the array

Specified by:

arrayLength in interface ArrayItem

Returns:

the number of members in this array

isEmpty

public boolean isEmpty()

Ask whether the array is empty

Specified by:

isEmpty in interface ArrayItem

Returns:

true if and only if the size of the array is zero

members

public java.lang.Iterable<GroundedValue> members()

Get the list of all members of the array

Specified by:

members in interface ArrayItem

Returns:

an iterator over the members of the array

removeSeveral

public ArrayItem removeSeveral(IntSet positions)

Remove zero or more members from the array

Specified by:

removeSeveral in interface ArrayItem

Parameters:

positions - the positions of the members to be removed (zero-based). A value that is out of range is ignored.

Returns:

a new array in which the requested member has been removed

remove

public ArrayItem remove(int pos)

Remove a member from the array

Specified by:

remove in interface ArrayItem

Parameters:

pos - the position of the member to be removed (zero-based). A value that is out of range results in an IndexOutOfBoundsException

Returns:

a new array in which the requested member has been removed

subArray

public ArrayItem subArray(int start,
                          int end)

Get a subarray given a start and end position

Specified by:

subArray in interface ArrayItem

Parameters:

start - the start position (zero based)

end - the end position (the position of the first item not to be returned) (zero based)

Returns:

a new array item containing the sub-array

Throws:

java.lang.IndexOutOfBoundsException - if start, or start+end, is out of range

insert

public ArrayItem insert(int position,
                        GroundedValue member)

Insert a new member into an array

Specified by:

insert in interface ArrayItem

Parameters:

position - the 0-based position that the new item will assume

member - the new member to be inserted

Returns:

a new array item with the new member inserted

Throws:

java.lang.IndexOutOfBoundsException - if position is out of range

concat

public ArrayItem concat(ArrayItem other)

Concatenate this array with another

Specified by:

concat in interface ArrayItem

Parameters:

other - the second array

Returns:

the concatenation of the two arrays; that is, an array containing first the members of this array, and then the members of the other array

getMembers

public java.util.List<GroundedValue> getMembers()

Get a list of the members of the array

Returns:

the list of members. Note that this returns the actual contained member array, and this is mutable. Changes to this array are permitted only if the caller knows what they are doing, for example during initial construction of an array that will not be presented to the user until construction has finished.

toShortString

public java.lang.String toShortString()

Provide a short string showing the contents of the item, suitable for use in error messages

Specified by:

toShortString in interface ArrayItem

Specified by:

toShortString in interface Function

Specified by:

toShortString in interface GroundedValue

Specified by:

toShortString in interface Item

Returns:

a depiction of the item suitable for use in error messages