org.basex.query.xpath.func
Class True

java.lang.Object
  extended by org.basex.query.ExprInfo
      extended by org.basex.query.xpath.expr.Expr
          extended by org.basex.query.xpath.func.Func
              extended by org.basex.query.xpath.func.True

public final class True
extends Func

Constructor for true() function.

Author:
Workgroup DBIS, University of Konstanz 2005-08, ISC License, Tim Petrowsky

Field Summary
 
Fields inherited from class org.basex.query.xpath.func.Func
desc
 
Constructor Summary
True(Expr[] arg)
          Function Constructor.
 
Method Summary
 boolean checkArguments()
          Checks validity/number of arguments.
 Bln comp(XPContext ctx)
          Optimizes the expression.
 Bln eval(XPContext ctx)
          Evaluates the expression with the specified context set.
 
Methods inherited from class org.basex.query.xpath.func.Func
evalArgs, plan, toString, usesPos, usesSize
 
Methods inherited from class org.basex.query.xpath.expr.Expr
indexEquivalent, indexSizes, returnedValue, sameAs
 
Methods inherited from class org.basex.query.ExprInfo
color, info, name
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

True

public True(Expr[] arg)
Function Constructor.

Parameters:
arg - expression array
Method Detail

eval

public Bln eval(XPContext ctx)
Description copied from class: Expr
Evaluates the expression with the specified context set. Additionally provides a context

Specified by:
eval in class Expr
Parameters:
ctx - query context
Returns:
resulting XPathValue

checkArguments

public boolean checkArguments()
Description copied from class: Func
Checks validity/number of arguments.

Specified by:
checkArguments in class Func
Returns:
result of comparison

comp

public Bln comp(XPContext ctx)
Description copied from class: Expr
Optimizes the expression.

Overrides:
comp in class Func
Parameters:
ctx - expression context
Returns:
optimized Expression