org.basex.query.expr
Class CFrag
java.lang.Object
org.basex.query.ExprInfo
org.basex.query.expr.Expr
org.basex.query.expr.Arr
org.basex.query.expr.CFrag
- Direct Known Subclasses:
- CAttr, CComm, CDoc, CElem, CPI, CText
public abstract class CFrag
- extends Arr
Fragment constructor.
- Author:
- Workgroup DBIS, University of Konstanz 2005-10, ISC License, Christian Gruen
Nested classes/interfaces inherited from class org.basex.query.expr.Expr |
Expr.Use |
Fields inherited from class org.basex.query.expr.Arr |
expr |
Constructor Summary |
CFrag(Expr... n)
Constructor. |
Methods inherited from class org.basex.query.expr.Expr |
addText, checkCtx, checkDbl, checkItr, e, ebv, i, indexAccessible, iter, sameAs, size, test, v |
CFrag
public CFrag(Expr... n)
- Constructor.
- Parameters:
n
- name
atomic
public abstract Nod atomic(QueryContext ctx)
throws QueryException
- Description copied from class:
Expr
- Evaluates the expression and returns the resulting item or
a
null
reference.
If this method is not overwritten, Expr.iter(org.basex.query.QueryContext)
must be implemented.
- Overrides:
atomic
in class Expr
- Parameters:
ctx
- query context
- Returns:
- iterator
- Throws:
QueryException
- query exception
uses
public final boolean uses(Expr.Use u,
QueryContext ctx)
- Description copied from class:
Expr
- Indicates if an expression uses the specified type.
Called by the compiler to perform certain optimizations.
true
is returned by default and thus assumed as "worst-case".
- Overrides:
uses
in class Arr
- Parameters:
u
- use type to be checkedctx
- query context
- Returns:
- result of check
returned
public final Return returned(QueryContext ctx)
- Description copied from class:
Expr
- Indicates the return type of an expression.
Called by the compiler to check if expressions can be reformulated.
null is returned by default.
- Overrides:
returned
in class Expr
- Parameters:
ctx
- query context
- Returns:
- result of check