org.jaxen.expr

Interface Expr

All Superinterfaces:
Serializable
Known Subinterfaces:
AdditiveExpr, BinaryExpr, EqualityExpr, FilterExpr, FunctionCallExpr, LiteralExpr, LocationPath, LogicalExpr, MultiplicativeExpr, NumberExpr, PathExpr, RelationalExpr, UnaryExpr, UnionExpr, VariableReferenceExpr
Known Implementing Classes:
DefaultAbsoluteLocationPath, DefaultAdditiveExpr, DefaultAndExpr, DefaultArithExpr, DefaultBinaryExpr, DefaultDivExpr, DefaultEqualityExpr, DefaultEqualsExpr, DefaultExpr, DefaultFilterExpr, DefaultFunctionCallExpr, DefaultGreaterThanEqualExpr, DefaultGreaterThanExpr, DefaultLessThanEqualExpr, DefaultLessThanExpr, DefaultLiteralExpr, DefaultLocationPath, DefaultLogicalExpr, DefaultMinusExpr, DefaultModExpr, DefaultMultiplicativeExpr, DefaultMultiplyExpr, DefaultNotEqualsExpr, DefaultNumberExpr, DefaultOrExpr, DefaultPathExpr, DefaultPlusExpr, DefaultRelationalExpr, DefaultRelativeLocationPath, DefaultTruthExpr, DefaultUnaryExpr, DefaultUnionExpr, DefaultVariableReferenceExpr

public interface Expr
extends Serializable

Represents an XPath expression. This is production 14 in the XPath 1.0 specification:
[14]      Expr       ::=      OrExpr

Method Summary

Object
evaluate(Context context)
Evaluate the expression in the given context, and return the result.
String
getText()
Returns a String containing the XPath expression.
Expr
simplify()
Simplifies the XPath expression.

Method Details

evaluate

public Object evaluate(Context context)
            throws JaxenException
Evaluate the expression in the given context, and return 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.
Parameters:
context - the context in which the expression is evaluated
Returns:
an object representing the result of the evaluation
Throws:
JaxenException -

getText

public String getText()
Returns a String containing the XPath expression.
Returns:
the text form of this XPath expression

simplify

public Expr simplify()
Simplifies the XPath expression. For example, the expression //para[1 = 1] could be simplified to //para. In practice, this is usually a noop. Jaxen does not currently perform any simplification.
Returns:
the simplified expression