Package org.basex.query.value.item

Class FItem

java.lang.Object

org.basex.query.expr.ExprInfo

org.basex.query.expr.Expr

org.basex.query.value.Value

org.basex.query.value.item.Item

org.basex.query.value.item.FItem

All Implemented Interfaces:

Iterable<Item>, XQFunction, XQFunctionExpr

Direct Known Subclasses:

FuncItem, XQJava, XQStruct

public abstract class FItem
extends Item
implements XQFunction

Abstract super class for function items. This class is inherited by XQMap, Array, and FuncItem.

Author:

BaseX Team 2005-24, BSD License, Leo Woerteler

Field Summary

Fields inherited from class org.basex.query.value.item.Item

NAN_DUMMY

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

type

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	FItem(Type type)	Constructor.

Method Summary

Modifier and Type	Method	Description
boolean	atomicEqual(Item item)	Compares items for atomic equality.
FItem	coerceTo(FuncType ft, QueryContext qc, CompileContext cc, InputInfo ii)	Converts this function item to the given function type.
boolean	equal(Item item, Collation coll, InputInfo ii)	Compares items for equality.
boolean	equals(Object obj)	This function is e.g. called by: If.optimize(CompileContext), Switch.optimize(CompileContext), Typeswitch.optimize(CompileContext), in order to discard identical expressions.
FuncType	funcType()	Returns the function type of this expression.
Item	materialize(Predicate<Data> test, InputInfo ii, QueryContext qc)	Returns a materialized version of this value without dependencies to persistent data.
boolean	materialized(Predicate<Data> test, InputInfo ii)	Checks if this value is materialized, i.e., contains no persistent database nodes or function items.

Methods inherited from class org.basex.query.value.item.Item

atomItem, atomValue, bool, cache, comparable, compare, dbl, ddo, dec, deepEqual, description, flt, hash, input, instanceOf, isItem, item, itemAt, iter, itr, refineType, refineType, reverse, sameType, score, seqType, size, string, stringInput, subsequence, test, toXml, typeId, write, xdmInfo

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

accept, checkUp, compactify, compile, copy, count, exprSize, get, has, inline, inlineable, isEmpty, iter, iterator, refineType, serialize, serialize, serialize, toJava, value

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

arg, args, atomIter, data, hasFreeVars, indexAccessible, info, isSimple, markTailCalls, mergeEbv, optimize, optimizePos, simplify, simplifyFor, typeCheck, uses, vacuous, visitAll

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

info, toErrorString, toString, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Methods inherited from interface org.basex.query.func.XQFunction

invoke, invokeInternal, invokeTail, stackFrameSize

Methods inherited from interface org.basex.query.func.XQFunctionExpr

annotations, arity, funcName, inline, paramName, vacuousBody

Constructor Detail

FItem

protected FItem(Type type)

Constructor.

Parameters:

type - function type

Method Detail

equal

public final boolean equal(Item item,
                           Collation coll,
                           InputInfo ii)
                    throws QueryException

Description copied from class: Item

Compares items for equality. Called by CmpV.OpV.

Specified by:

equal in class Item

Parameters:

item - item to be compared

coll - collation (can be null)

ii - input info (can be null)

Returns:

result of check

Throws:

QueryException - query exception

atomicEqual

public final boolean atomicEqual(Item item)

Description copied from class: Item

Compares items for atomic equality. Called by FnAtomicEqual.

Overrides:

atomicEqual in class Item

Parameters:

item - item to be compared

Returns:

result of check

funcType

public final FuncType funcType()

Description copied from class: Expr

Returns the function type of this expression.

Specified by:

funcType in interface XQFunctionExpr

Overrides:

funcType in class Expr

Returns:

function type, or null if expression yields no functions

materialize

public Item materialize(Predicate<Data> test,
                        InputInfo ii,
                        QueryContext qc)
                 throws QueryException

Description copied from class: Value

Returns a materialized version of this value without dependencies to persistent data. Raises an error if the value contains function items.

Overrides:

materialize in class Item

Parameters:

test - test to check if a node can be adopted unchanged

ii - input info (can be null)

qc - query context

Returns:

materialized value

Throws:

QueryException - query exception

materialized

public boolean materialized(Predicate<Data> test,
                            InputInfo ii)
                     throws QueryException

Description copied from class: Value

Checks if this value is materialized, i.e., contains no persistent database nodes or function items.

Overrides:

materialized in class Item

Parameters:

test - test to check if a node can be adopted unchanged

ii - input info (can be null)

Returns:

result of check

Throws:

QueryException - query exception

coerceTo

public FItem coerceTo(FuncType ft,
                      QueryContext qc,
                      CompileContext cc,
                      InputInfo ii)
               throws QueryException

Converts this function item to the given function type.

Parameters:

ft - function type

qc - query context

cc - compilation context (null during runtime)

ii - input info (can be null)

Returns:

coerced item

Throws:

QueryException - query exception

equals

public final boolean equals(Object obj)

Description copied from class: Expr

This function is e.g. called by:

• If.optimize(CompileContext), Switch.optimize(CompileContext), Typeswitch.optimize(CompileContext), in order to discard identical expressions.
• CmpR.mergeEbv(Expr, boolean, CompileContext) or CmpSR.mergeEbv(Expr, boolean, CompileContext), in order to merge expressions with identical input.
• CmpG.optimize(CompileContext) or CmpV.optimize(CompileContext), in order to pre-evaluate equality tests.
• CmpG.optimize(CompileContext), in order to compare the start and end value.
• PathCache, in order to find identical root values at runtime.

Specified by:

equals in class Expr