org.basex.query.expr
Class And
java.lang.Object
org.basex.query.ExprInfo
org.basex.query.expr.Expr
org.basex.query.expr.Arr
org.basex.query.expr.And
public final class And
- extends Arr
And expression.
- 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 |
And(Expr[] e)
Constructor. |
Methods inherited from class org.basex.query.expr.Expr |
addText, checkCtx, checkDbl, checkItr, e, ebv, i, iter, sameAs, size, test, v |
And
public And(Expr[] e)
- Constructor.
- Parameters:
e
- expression list
comp
public Expr comp(QueryContext ctx)
throws QueryException
- Description copied from class:
Expr
- Optimizes and compiles the expression.
- Overrides:
comp
in class Arr
- Parameters:
ctx
- query context
- Returns:
- optimized Expression
- Throws:
QueryException
- query exception
atomic
public Bln 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
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 Expr
- Parameters:
ctx
- query context
- Returns:
- result of check
indexAccessible
public boolean indexAccessible(IndexContext ic)
throws QueryException
- Description copied from class:
Expr
- Checks if an index can be used for query evaluation.
- Overrides:
indexAccessible
in class Expr
- Parameters:
ic
- index context
- Returns:
- true if an index can be used
- Throws:
QueryException
- query exception
indexEquivalent
public Expr indexEquivalent(IndexContext ic)
throws QueryException
- Description copied from class:
Expr
- Returns an equivalent expression which accesses an index structure.
Must be called if
Expr.indexAccessible(org.basex.query.IndexContext)
is implemented for an
expression.
- Overrides:
indexEquivalent
in class Arr
- Parameters:
ic
- index context
- Returns:
- Equivalent index-expression or null
- Throws:
QueryException
- query exception
toString
public String toString()
- Specified by:
toString
in class ExprInfo