org.basex.query.func
Class FNSimple

java.lang.Object
  extended by org.basex.query.ExprInfo
      extended by org.basex.query.expr.Expr
          extended by org.basex.query.expr.Arr
              extended by org.basex.query.func.Fun
                  extended by org.basex.query.func.FNSimple

public final class FNSimple
extends Fun

Simple functions.

Author:
Workgroup DBIS, University of Konstanz 2005-10, ISC 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.func.Fun
func
 
Fields inherited from class org.basex.query.expr.Arr
expr
 
Constructor Summary
FNSimple()
           
 
Method Summary
 Item atomic(QueryContext ctx)
          Evaluates the expression and returns the resulting item or a null reference.
 Expr c(QueryContext ctx)
          Compiles the function.
 Iter iter(QueryContext ctx)
          Evaluates the expression and returns an iterator on the resulting items.
 Return returned(QueryContext ctx)
          Indicates the return type of an expression.
 
Methods inherited from class org.basex.query.func.Fun
comp, info, init, plan, toString
 
Methods inherited from class org.basex.query.expr.Arr
duplicates, indexEquivalent, removable, remove, uses
 
Methods inherited from class org.basex.query.expr.Expr
addText, checkCtx, checkDbl, checkItr, e, ebv, i, indexAccessible, sameAs, size, test, v
 
Methods inherited from class org.basex.query.ExprInfo
color, name
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

FNSimple

public FNSimple()
Method Detail

iter

public Iter iter(QueryContext ctx)
          throws QueryException
Description copied from class: Expr
Evaluates the expression and returns an iterator on the resulting items. If this method is not overwritten, Expr.atomic(org.basex.query.QueryContext) must be implemented.

Overrides:
iter in class Expr
Parameters:
ctx - query context
Returns:
resulting item
Throws:
QueryException - query exception

atomic

public Item 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

c

public Expr c(QueryContext ctx)
       throws QueryException
Description copied from class: Fun
Compiles the function.

Overrides:
c in class Fun
Parameters:
ctx - query context
Returns:
evaluated item
Throws:
QueryException - query exception

returned

public 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 Fun
Parameters:
ctx - query context
Returns:
result of check