org.basex.query.xquery.expr
Class Pred

java.lang.Object
  extended by org.basex.query.ExprInfo
      extended by org.basex.query.xquery.expr.Expr
          extended by org.basex.query.xquery.expr.Arr
              extended by org.basex.query.xquery.expr.Pred
Direct Known Subclasses:
PredIter

public class Pred
extends Arr

Predicate expression.

Author:
Workgroup DBIS, University of Konstanz 2005-08, ISC License, Christian Gruen

Nested Class Summary
 
Nested classes/interfaces inherited from class org.basex.query.xquery.expr.Expr
Expr.Return, Expr.Using
 
Field Summary
 
Fields inherited from class org.basex.query.xquery.expr.Arr
expr
 
Constructor Summary
Pred(Expr r, Expr[] e)
          Constructor.
 
Method Summary
 Expr comp(XQContext ctx)
          Optimizes and compiles the expression.
 java.lang.String info()
          Returns a string description of the expression.
 Iter iter(XQContext ctx)
          Evaluates the expression and returns an iterator on the resulting items.
 void plan(Serializer ser)
          Recursively sends the abstract syntax of this expression to the specified serializer.
 java.lang.String toString()
           
 boolean uses(Expr.Using u)
          Indicates if an expression uses the specified type.
 
Methods inherited from class org.basex.query.xquery.expr.Arr
returned
 
Methods inherited from class org.basex.query.xquery.expr.Expr
e, i
 
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

Pred

public Pred(Expr r,
            Expr[] e)
Constructor.

Parameters:
r - expression
e - predicates
Method Detail

comp

public final Expr comp(XQContext ctx)
                throws XQException
Description copied from class: Expr
Optimizes and compiles the expression.

Overrides:
comp in class Arr
Parameters:
ctx - query context
Returns:
optimized Expression
Throws:
XQException - evaluation exception

iter

public Iter iter(XQContext ctx)
          throws XQException
Description copied from class: Expr
Evaluates the expression and returns an iterator on the resulting items.

Specified by:
iter in class Expr
Parameters:
ctx - query context
Returns:
resulting item
Throws:
XQException - evaluation exception

uses

public final boolean uses(Expr.Using u)
Description copied from class: Expr
Indicates if an expression uses the specified type. Called by the compiler to check if expressions can be reformulated. true is returned by default.

Overrides:
uses in class Arr
Parameters:
u - using flag
Returns:
result of check

toString

public final java.lang.String toString()
Specified by:
toString in class ExprInfo

info

public final java.lang.String info()
Description copied from class: ExprInfo
Returns a string description of the expression. Contrary to the ExprInfo.toString() method, the current expressions aren't included in the output.

Overrides:
info in class ExprInfo
Returns:
result of check

plan

public final void plan(Serializer ser)
                throws java.io.IOException
Description copied from class: ExprInfo
Recursively sends the abstract syntax of this expression to the specified serializer.

Overrides:
plan in class Arr
Parameters:
ser - serializer
Throws:
java.io.IOException - exception