Package org.basex.query.value.item

Class XQData

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

org.basex.query.value.item.XQData

All Implemented Interfaces:

Iterable<Item>, XQFunction, XQFunctionExpr

Direct Known Subclasses:

XQArray, XQMap

public abstract class XQData
extends FItem

Function item with a known data structure (map, array).

Author:

BaseX Team 2005-21, BSD License, Christian Gruen

Field Summary

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

UNDEF

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

type

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	XQData(FuncType type)	Constructor.

Method Summary

Modifier and Type	Method	Description
final int	arity()	Number of arguments this function takes.
final FItem	coerceTo(FuncType ft, QueryContext qc, InputInfo ii, boolean optimize)	Coerces this function item to the given function type.
final boolean	equals(Object obj)	This function is e.g.
final QNm	funcName()	Name of this function, null means anonymous function.
abstract Value	get(Item key, InputInfo ii)	Gets a value from this item.
final Expr	inline(Expr[] exprs, CompileContext cc)	Tries to inline this function with the given arguments.
final Value	invokeInternal(QueryContext qc, InputInfo ii, Value[] args)	Internally invokes this function with the given arguments.
final int	stackFrameSize()	Size of this function's stack frame.
abstract void	string(boolean indent, TokenBuilder tb, int level, InputInfo ii)	Returns a string representation of the item.
final boolean	vacuousBody()	Checks if this function returns vacuous results (see Expr.vacuous()).

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

annotations, deep, eq, funcType, refineType, sameKey, string

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

atomItem, atomSize, atomValue, bool, cache, comparable, dbl, ddo, dec, description, diff, ebv, equiv, flt, hash, input, instanceOf, item, itemAt, iter, itr, materialize, persistent, plan, reverse, score, seqType, size, subsequence, test, typeId, xdmInfo

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

accept, checkUp, compile, copy, count, exprSize, has, inline, inlineable, isEmpty, isItem, iter, iterator, materialize, serialize, serialize, serialize, toJava, value

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

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

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

plan, toErrorString, 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, invokeTail

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

paramName

Constructor Details

XQData

protected XQData(FuncType type)

Constructor.

Parameters:

type - type

Method Details

arity

public final int arity()

Description copied from interface: XQFunctionExpr

Number of arguments this function takes.

Returns:

function arity

funcName

public final QNm funcName()

Description copied from interface: XQFunctionExpr

Name of this function, null means anonymous function.

Returns:

name or null

inline

public final Expr inline(Expr[] exprs,
 CompileContext cc)

Description copied from interface: XQFunctionExpr

Tries to inline this function with the given arguments.

Parameters:

exprs - arguments

cc - compilation context

Returns:

the expression to inline if successful, null otherwise

vacuousBody

public final boolean vacuousBody()

Description copied from interface: XQFunctionExpr

Checks if this function returns vacuous results (see Expr.vacuous()).

Returns:

result of check

invokeInternal

public final Value invokeInternal(QueryContext qc,
 InputInfo ii,
 Value[] args)
                           throws QueryException

Description copied from interface: XQFunction

Internally invokes this function with the given arguments.

Parameters:

qc - query context

ii - input info

args - arguments

Returns:

resulting value

Throws:

QueryException - query exception

stackFrameSize

public final int stackFrameSize()

Description copied from interface: XQFunction

Size of this function's stack frame.

Returns:

stack frame size

coerceTo

public final FItem coerceTo(FuncType ft,
 QueryContext qc,
 InputInfo ii,
 boolean optimize)
                     throws QueryException

Description copied from class: FItem

Coerces this function item to the given function type.

Specified by:

coerceTo in class FItem

Parameters:

ft - function type

qc - query context

ii - input info

optimize - optimize resulting item

Returns:

coerced item

Throws:

QueryException - query exception

get

public abstract Value get(Item key,
 InputInfo ii)
                   throws QueryException

Gets a value from this item.

Parameters:

key - key to look for (must not be null)

ii - input info

Returns:

bound value if found, the empty sequence () otherwise

Throws:

QueryException - query exception

string

public abstract void string(boolean indent,
 TokenBuilder tb,
 int level,
 InputInfo ii)
                     throws QueryException

Returns a string representation of the item.

Parameters:

indent - indent output

tb - token builder

level - current level

ii - input info

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) or Pos.get(Expr, CmpV.OpV, InputInfo, 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