org.basex.query.expr

Class CFrag

java.lang.Object

org.basex.data.ExprInfo

org.basex.query.expr.Expr

org.basex.query.expr.ParseExpr

org.basex.query.expr.Arr

org.basex.query.expr.CFrag

Direct Known Subclasses:

CComm, CDoc, CName, CTxt

public abstract class CFrag
extends Arr

Fragment constructor.

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.expr.Arr

expr

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

input, size, type

Method Summary

Methods

Modifier and Type	Method and Description
abstract ANode	item(QueryContext ctx, InputInfo ii) Evaluates the expression and returns the resulting item or a null reference, if the expression yields an empty sequence.
protected java.lang.String	toString(java.lang.String pref) Prints the array with the specified separator.
boolean	uses(Expr.Use u) Indicates if an expression uses the specified type or operation.

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

allAreValues, comp, count, indexEquivalent, plan, removable, remove

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, iter, optPre, preEval, size, test, type, value

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

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

Methods inherited from class org.basex.data.ExprInfo

description, info, toString

Methods inherited from class java.lang.Object

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

Method Detail

item

public abstract ANode item(QueryContext ctx,
         InputInfo ii)
                    throws QueryException

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 ParseExpr

Parameters:

ctx - query context

ii - input info

Returns:

iterator

Throws:

QueryException - query exception

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 Arr

Parameters:

u - type/operation to be found

Returns:

result of check

toString

protected java.lang.String toString(java.lang.String pref)

Description copied from class: Arr

Prints the array with the specified separator.

Overrides:

toString in class Arr

Parameters:

pref - separator

Returns:

string representation