org.basex.query.func

Class InlineFunc

java.lang.Object

org.basex.data.ExprInfo

org.basex.query.expr.Expr

org.basex.query.expr.ParseExpr

org.basex.query.expr.Single

org.basex.query.func.UserFunc

org.basex.query.func.InlineFunc

public final class InlineFunc
extends UserFunc

Inline function.

Author:

BaseX Team 2005-12, BSD License, Leo Woerteler

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.func.UserFunc

ann, args, declared, name, ret, updating

Fields inherited from class org.basex.query.expr.Single

expr

Fields inherited from class org.basex.query.expr.ParseExpr

input, size, type

Constructor Summary

Constructors

Constructor and Description
InlineFunc(InputInfo ii, SeqType r, Var[] v, Expr e, Ann a) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
Expr	comp(QueryContext ctx) Compiles and optimizes the expression, assigns data types and cardinalities.
FuncItem	item(QueryContext ctx, InputInfo ii) Evaluates the expression and returns the resulting item or a null reference, if the expression yields an empty sequence.
ValueIter	iter(QueryContext ctx) Evaluates the expression and returns an iterator on the resulting items.
void	plan(Serializer ser) Serializes the expression tree.
boolean	removable(Var v) Checks if the specified variable is replaceable by a context item.
Expr	remove(Var v) Substitutes all VarRef expressions for the given variable by a Context reference.
java.lang.String	toString()
boolean	uses(Expr.Use u) Indicates if an expression uses the specified type or operation.
Value	value(QueryContext ctx) Evaluates the expression and returns the resulting value.

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

count

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

checkBln, checkColl, checkCreate, checkCtx, checkDbl, checkDBNode, checkEStr, checkEStr, checkIO, checkItem, checkItr, checkItr, checkMap, checkNode, checkNoEmpty, checkStr, checkType, checkUp, checkUp, checkWrite, compBln, ebv, optPre, preEval, size, test, type

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

addText, compEbv, hasFreeVars, indexAccessible, indexEquivalent, isEmpty, isFunction, isItem, isVacuous, isValue, iterable, markTailCalls, sameAs

Methods inherited from class org.basex.data.ExprInfo

description, info

Methods inherited from class java.lang.Object

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

Constructor Detail

InlineFunc

public InlineFunc(InputInfo ii,
          SeqType r,
          Var[] v,
          Expr e,
          Ann a)

Constructor.

Parameters:

ii - input info

r - return type

v - arguments

e - function body

a - annotations

Method Detail

comp

public Expr comp(QueryContext ctx)
          throws QueryException

Description copied from class: Expr

Compiles and optimizes the expression, assigns data types and cardinalities.

Overrides:

comp in class UserFunc

Parameters:

ctx - query context

Returns:

optimized expression

Throws:

QueryException - query exception

item

public FuncItem item(QueryContext ctx,
            InputInfo ii)

Description copied from class: Expr

Evaluates the expression and returns the resulting item or a null reference, if the expression yields an empty sequence. If this method is not overwritten, Expr.iter(org.basex.query.QueryContext) must be implemented by an expression, as it may be called by this method.

Overrides:

item in class UserFunc

Parameters:

ctx - query context

ii - input info

Returns:

iterator

value

public Value value(QueryContext ctx)

Description copied from class: Expr

Evaluates the expression and returns the resulting value.

Overrides:

value in class UserFunc

Parameters:

ctx - query context

Returns:

iterator

iter

public ValueIter iter(QueryContext ctx)

Description copied from class: Expr

Evaluates the expression and returns an iterator on the resulting items. If this method is not overwritten, Expr.item(org.basex.query.QueryContext, org.basex.util.InputInfo) must be implemented by an expression, as it may be called by this method.

Overrides:

iter in class UserFunc

Parameters:

ctx - query context

Returns:

resulting item

uses

public boolean uses(Expr.Use u)

Description copied from class: Expr

Indicates if an expression uses the specified type or operation. This method is called by numerous Expr.comp(org.basex.query.QueryContext) methods to test the properties of sub-expressions. It will return true as soon as at least one test is successful.

Overrides:

uses in class Single

Parameters:

u - type/operation to be found

Returns:

result of check

removable

public boolean removable(Var v)

Description copied from class: Expr

Checks if the specified variable is replaceable by a context item. The following tests might return false:

• Preds.removable(org.basex.query.util.Var), if one of the variables is used within a predicate.
• MixedPath.removable(org.basex.query.util.Var), if the variable occurs within the path.
• Group.removable(org.basex.query.util.Var), as the group by expression depends on variable references.

This method is called by GFLWOR.comp(org.basex.query.QueryContext) to rewrite where clauses into predicates.

Overrides:

removable in class Single

Parameters:

v - variable to be replaced

Returns:

result of check

remove

public Expr remove(Var v)

Description copied from class: Expr

Substitutes all VarRef expressions for the given variable by a Context reference. This method is called by GFLWOR.comp(org.basex.query.QueryContext) to rewrite where clauses as predicates.

Overrides:

remove in class Single

Parameters:

v - variable to be replaced

Returns:

new expression

plan

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

Description copied from class: ExprInfo

Serializes the expression tree.

Overrides:

plan in class UserFunc

Parameters:

ser - serializer

Throws:

java.io.IOException - I/O exception

toString

public java.lang.String toString()

Overrides:

toString in class UserFunc