com.saxonica.sdoc
Class SelectionParser

java.lang.Object
  net.sf.saxon.expr.ExpressionParser
      com.saxonica.sdoc.SelectionParser

public class SelectionParser

extends ExpressionParser

This class parses the two XPath subsets defined in XML Schema for handling the "selector" and "field" attributes of the , , and elements.

Nested Class Summary

Nested classes inherited from class net.sf.saxon.expr.ExpressionParser

ExpressionParser.ForClause, ExpressionParser.TemporaryContainer

Field Summary

Fields inherited from class net.sf.saxon.expr.ExpressionParser

env, language, nameChecker, rangeVariables, scanOnly, SEQUENCE_TYPE, t, XPATH, XQUERY, XSLT_PATTERN

Constructor Summary

SelectionParser()

Method Summary

static PathSelection	makePathSelection(Expression path, boolean failIfInvalid) Make a PathSelection object from a suitable expression.
Selection	parseSelector(java.lang.String expression, StaticContext env, boolean isField) Parse a string representing the restricted XPath expression allowed in an XML Schema selector or field attribute
protected Expression	parseStepExpression() Override the general XPath parsing of a StepExpression to support the simpler kind of Step used in XML Schema selectors

Methods inherited from class net.sf.saxon.expr.ExpressionParser

currentTokenDisplay, declareRangeVariable, expect, getLanguage, getRangeVariableStack, getTokenizer, grumble, grumble, isKeyword, makeLocalNameTest, makeNameCode, makeNamespaceTest, makeNameTest, makeStringLiteral, makeTracer, nextToken, parse, parseConstructor, parseExpression, parseExprSingle, parseExtensionExpression, parseForExpression, parseMappingExpression, parseNodeTest, parsePattern, parseRelativePath, parseRemainingPath, parseSequenceType, parseSequenceType, parseTypeswitchExpression, parseValidateExpression, setLocation, setLocation, setRangeVariableStack, setScanOnly, undeclareRangeVariable, warning

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SelectionParser

public SelectionParser()

Method Detail

parseSelector

public Selection parseSelector(java.lang.String expression,
                               StaticContext env,
                               boolean isField)
                        throws XPathException

Parse a string representing the restricted XPath expression allowed in an XML Schema selector or field attribute

Parameters:

expression - the expression expressed as a String

env - the static context for the expression

isField - true if the attribute is a "field" attribute, false if it is a "selector" attribute

Returns:

an Expression object representing the result of parsing

Throws:

XPathException - if the expression contains a syntax error

makePathSelection

public static PathSelection makePathSelection(Expression path,
                                              boolean failIfInvalid)
                                       throws XPathException

Make a PathSelection object from a suitable expression. This method is public because it is also used by the optimizer for SequentialCopy expressions.

Parameters:

path - the input expression

failIfInvalid - if true, the method will throw an exception if the expression is unsuitable. If false, it will return null if the expression is unsuitable.

Returns:

The PathSelection object, or null if the expression is unsuitable for use as a PathSelection and the failIfInvalid argument was set to false.

Throws:

XPathException - if the expression is unsuitable for use as a PathSelection and the failIfInvalid argument was set to true.

parseStepExpression

protected Expression parseStepExpression()
                                  throws StaticError

Override the general XPath parsing of a StepExpression to support the simpler kind of Step used in XML Schema selectors

Overrides:

parseStepExpression in class ExpressionParser

Returns:

an Expression, which will always be either an AxisExpression or a ContextItemExpression

Throws:

StaticError