org.jaxen.expr
Interface Predicate
- Serializable
- DefaultPredicate
public interface Predicate
extends Serializable
Represents an XPath predicate such as
[position() = last()]
.
This is production 8 and 9 in the
XPath 1.0 specification:
[8] Predicate ::= '[' PredicateExpr ']'
[9] PredicateExpr ::= Expr
Object | evaluate(Context context) - Evaluates this predicate's expression and returns the result.
|
Expr | getExpr() - Returns the expression in this predicate.
|
String | getText() - Returns the string form of the predicate,
including the square brackets.
|
void | setExpr(Expr expr) - Change the expression used by this predicate.
|
void | simplify() - Simplify the expression in this predicate.
|
evaluate
public Object evaluate(Context context)
throws JaxenException
Evaluates this predicate's expression and returns the result.
The result will be a java.lang.Double
for expressions that
return a number, a java.lang.String
for expressions that
return a string, a java.lang.Boolean
for expressions that
return a boolean, and a java.util.List
for expressions that
return a node-set. In the latter case, the elements of the list are
the actual objects from the source document model. Copies are not made.
context
- the context in which the expression is evaluated
- an object representing the result of the evaluation
getExpr
public Expr getExpr()
Returns the expression in this predicate.
- the expression between the brackets
getText
public String getText()
Returns the string form of the predicate,
including the square brackets.
- the bracketed form of this predicate
setExpr
public void setExpr(Expr expr)
Change the expression used by this predicate.
expr
- the new expression
simplify
public void simplify()
Simplify the expression in this predicate.