org.basex.query.xquery.expr
Class Context

java.lang.Object
  extended by org.basex.query.ExprInfo
      extended by org.basex.query.xquery.expr.Expr
          extended by org.basex.query.xquery.expr.Context

public final class Context
extends Expr

Context Item.

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
 
Constructor Summary
Context()
           
 
Method Summary
 Expr comp(XQContext ctx)
          Optimizes and compiles 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 use)
          Indicates if an expression uses the specified type.
 
Methods inherited from class org.basex.query.xquery.expr.Expr
e, i, returned
 
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

Context

public Context()
Method Detail

comp

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

Specified by:
comp in class Expr
Parameters:
ctx - query context
Returns:
optimized Expression

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 boolean uses(Expr.Using use)
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 Expr
Parameters:
use - using flag
Returns:
result of check

plan

public 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.

Specified by:
plan in class ExprInfo
Parameters:
ser - serializer
Throws:
java.io.IOException - exception

toString

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