org.basex.query.item

Class ItemSeq

java.lang.Object

org.basex.data.ExprInfo

org.basex.query.expr.Expr

org.basex.query.item.Value

org.basex.query.item.Seq

org.basex.query.item.ItemSeq

All Implemented Interfaces:

java.lang.Iterable<Item>

public final class ItemSeq
extends Seq

Sequence, containing at least two items.

Author:

BaseX Team 2005-12, BSD License, Christian Gruen

Nested Class Summary

Nested classes/interfaces inherited from class org.basex.query.expr.Expr

Expr.Use

Field Summary

Fields inherited from class org.basex.query.item.Value

type

Method Summary

Methods

Modifier and Type	Method and Description
Item	ebv(QueryContext ctx, InputInfo ii) Checks if the iterator can be dissolved into an effective boolean value.
boolean	homogenous() Checks if all items of this value share the same type.
Item	itemAt(long pos) Gets the item at the given position in the value.
boolean	iterable() Returns true if the expression is iterable, i.e., if it does not contain any duplicates and if all results are sorted.
void	plan(Serializer ser) Serializes the expression tree.
boolean	sameAs(Expr cmp) Compares the current and specified expression for equality.
java.lang.Object	toJava() Returns a Java representation of the value.
SeqType	type() Returns the sequence type of the evaluated value.
int	writeTo(Item[] arr, int start) Writes this value's items out to the given array.

Methods inherited from class org.basex.query.item.Seq

get, hash, item, iter, size, test, toString

Methods inherited from class org.basex.query.item.Value

cache, comp, count, data, description, info, isValue, iter, iterator, removable, remove, uses, value

Methods inherited from class org.basex.query.expr.Expr

addText, compEbv, hasFreeVars, indexAccessible, indexEquivalent, isEmpty, isFunction, isItem, isVacuous, markTailCalls

Methods inherited from class java.lang.Object

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

Method Detail

toJava

public java.lang.Object toJava()
                        throws QueryException

Description copied from class: Value

Returns a Java representation of the value.

Specified by:

toJava in class Value

Returns:

Java object

Throws:

QueryException - query exception

ebv

public Item ebv(QueryContext ctx,
       InputInfo ii)
         throws QueryException

Description copied from class: Expr

Checks if the iterator can be dissolved into an effective boolean value. If not, returns an error. If yes, returns the first value - which can be also be e.g. an integer, which is later evaluated as numeric predicate.

Specified by:

ebv in class Expr

Parameters:

ctx - query context

ii - input info

Returns:

item

Throws:

QueryException - query exception

type

public SeqType type()

Description copied from class: Expr

Returns the sequence type of the evaluated value. For simplicity, some types have been summarized. E.g., all numbers are treated as integers.

Specified by:

type in class Expr

Returns:

result of check

iterable

public boolean iterable()

Description copied from class: Expr

Returns true if the expression is iterable, i.e., if it does not contain any duplicates and if all results are sorted. This method is called e.g. by AxisPath.

Overrides:

iterable in class Expr

Returns:

result of check

sameAs

public boolean sameAs(Expr cmp)

Description copied from class: Expr

Compares the current and specified expression for equality.

Overrides:

sameAs in class Expr

Parameters:

cmp - expression to be compared

Returns:

result of check

writeTo

public int writeTo(Item[] arr,
          int start)

Description copied from class: Value

Writes this value's items out to the given array.

Specified by:

writeTo in class Value

Parameters:

arr - array to write to

start - start position

Returns:

number of written items

itemAt

public Item itemAt(long pos)

Description copied from class: Value

Gets the item at the given position in the value.

Specified by:

itemAt in class Value

Parameters:

pos - position

Returns:

item

homogenous

public boolean homogenous()

Description copied from class: Value

Checks if all items of this value share the same type.

Specified by:

homogenous in class Value

Returns:

result of check

plan

public void plan(Serializer ser)
          throws java.io.IOException

Description copied from class: ExprInfo

Serializes the expression tree.

Specified by:

plan in class ExprInfo

Parameters:

ser - serializer

Throws:

java.io.IOException - I/O exception