org.exolab.adaptx.xpath
Interface XPathExpression

All Known Subinterfaces:

BinaryExpr, EqualityExpr, FilterExpr, GroupedExpression, LocationStep, NodeExpression, PathComponent

All Known Implementing Classes:

AbstractPathComponent, BooleanFunctionCall, Concat, Contains, CountFunctionCall, ErrorExpr, ErrorFunctionCall, ExtensionFunctionCall, FalseFunctionCall, FormatNumber, FunctionCall, FunctionCallImpl, IdFunctionCall, IdRefFunctionCall, LangFunctionCall, LastFunctionCall, Normalize, NotFunctionCall, NumberFunctionCall, PathExpr, PositionFunctionCall, PredicateExpr, PrimaryExpr, SelectExpr, StartsWith, StringFunctionCall, StringLength, Substring, SubstringAfter, SubstringBefore, SumFunctionCall, TextFunctionCall, Translate, TrueFunctionCall, UnionExpr, VariableReference, XMLNamesFunctionCall

public interface XPathExpression

Interface representing an XPath expression. An XPath expression is thread-safe and can be evaluated multiple times concurrently. It is a compiled version of the textual XPath expression and can be cached for later use.

Version:

$Revision: 3738 $

Author:

Keith Visco, Assaf Arkin

Field Summary

static short	BOOLEAN The Boolean expression type.
static short	ERROR Expression of type error.
static short	FILTER_EXPR The FilterExpr expression type.
static short	LOCATION_PATH The LocationPath expression type.
static short	NODE_TEST The NodeTest expressions type
static short	NUMBER The NodeTest expressions type
static short	PATH_EXPR The PathExpr expression type.
static short	PRIMARY The Primary expression type.
static short	STEP The Step expression type.
static short	STRING The String expression type.
static short	UNION_EXPR The union expression type.

Method Summary

XPathResult	evaluate(XPathContext context) Evaluates the expression and returns the XPath result.
short	getExprType() Returns the type of this expression.
java.lang.String	toString() Returns the XPath expression as a string.

Field Detail

ERROR

static final short ERROR

Expression of type error.

See Also:

Constant Field Values

BOOLEAN

static final short BOOLEAN

The Boolean expression type.

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Constant Field Values

FILTER_EXPR

static final short FILTER_EXPR

The FilterExpr expression type.

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Constant Field Values

LOCATION_PATH

static final short LOCATION_PATH

The LocationPath expression type.

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Constant Field Values

NODE_TEST

static final short NODE_TEST

The NodeTest expressions type

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Constant Field Values

NUMBER

static final short NUMBER

The NodeTest expressions type

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Constant Field Values

PATH_EXPR

static final short PATH_EXPR

The PathExpr expression type.

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Constant Field Values

PRIMARY

static final short PRIMARY

The Primary expression type.

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Constant Field Values

STEP

static final short STEP

The Step expression type.

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Constant Field Values

STRING

static final short STRING

The String expression type.

See Also:

Constant Field Values

UNION_EXPR

static final short UNION_EXPR

The union expression type.

See Also:

Constant Field Values

Method Detail

getExprType

short getExprType()

Returns the type of this expression.

Returns:

The type of this expression

evaluate

XPathResult evaluate(XPathContext context)
                     throws XPathException

Evaluates the expression and returns the XPath result.

Parameters:

context - The XPathContext to use during evaluation.

Returns:

The XPathResult (not null).

Throws:

XPathException - if an error occured while evaluating this expression.

toString

java.lang.String toString()

Returns the XPath expression as a string. The returned value is a valid XPath expression that can be parsed into an equivalent XPathExpression object.

Overrides:

toString in class java.lang.Object

Returns:

The XPath expression as a string