org.exist.xquery.functions
Class FunMatches
java.lang.Object
org.exist.xquery.AbstractExpression
org.exist.xquery.PathExpr
org.exist.xquery.Function
org.exist.xquery.functions.FunMatches
- All Implemented Interfaces:
- CompiledXQuery, Expression, IndexUseReporter, Optimizable, CompiledExpression
- Direct Known Subclasses:
- FunReplace, FunTokenize
public class FunMatches
- extends Function
- implements Optimizable, IndexUseReporter
Implements the fn:matches() function.
Based on the java.util.regex package for regular expression support.
- Author:
- Wolfgang Meier (wolfgang@exist-db.org)
Fields inherited from interface org.exist.xquery.Expression |
DOT_TEST, EXPRESSION_ID_INVALID, IGNORE_CONTEXT, IN_NODE_CONSTRUCTOR, IN_PREDICATE, IN_UPDATE, IN_WHERE_CLAUSE, NEED_INDEX_INFO, NO_CONTEXT_ID, SINGLE_STEP_EXECUTION, USE_TREE_TRAVERSAL |
Methods inherited from class org.exist.xquery.Function |
accept, createFunction, dump, getArgument, getArgumentCount, getArguments, getASTNode, getCardinality, getName, getParent, getSignature, isCalledAs, setASTNode, setParent, setPrimaryAxis, toString |
Methods inherited from class org.exist.xquery.PathExpr |
add, add, addPath, addPredicate, dump, getContext, getDocumentSet, getExpression, getLastExpression, getLength, getLiteralValue, getSource, isValid, replaceExpression, replaceLastExpression, setContext, setSource |
Methods inherited from interface org.exist.xquery.Expression |
accept, dump, eval, getASTNode, getCardinality, getContextDocSet, getContextId, getExpressionId, setASTNode, setContextDocSet, setPrimaryAxis |
signatures
public static final FunctionSignature[] signatures
FunMatches
public FunMatches(XQueryContext context,
FunctionSignature signature)
- Parameters:
context
-
setArguments
public void setArguments(List arguments)
throws XPathException
- Description copied from class:
Function
- Set the (static) arguments for this function from a list of expressions.
This will also check the type and cardinality of the
passed argument expressions.
- Overrides:
setArguments
in class Function
- Throws:
XPathException
canOptimize
public boolean canOptimize(Sequence contextSequence)
- Specified by:
canOptimize
in interface Optimizable
optimizeOnSelf
public boolean optimizeOnSelf()
- Specified by:
optimizeOnSelf
in interface Optimizable
getOptimizeAxis
public int getOptimizeAxis()
- Specified by:
getOptimizeAxis
in interface Optimizable
preSelect
public NodeSet preSelect(Sequence contextSequence,
boolean useContext)
throws XPathException
- Specified by:
preSelect
in interface Optimizable
- Throws:
XPathException
getDependencies
public int getDependencies()
- Description copied from class:
AbstractExpression
- Returns
Dependency.DEFAULT_DEPENDENCIES
.
- Specified by:
getDependencies
in interface Expression
- Overrides:
getDependencies
in class Function
- Returns:
- set of bit-flags
- See Also:
Expression.getDependencies()
returnsType
public int returnsType()
- Description copied from interface:
Expression
- The static return type of the expression.
This method should return one of the type constants defined in class
Type
. If the return type cannot be determined
statically, return Type.ITEM.
- Specified by:
returnsType
in interface Expression
- Overrides:
returnsType
in class Function
hasUsedIndex
public boolean hasUsedIndex()
- Specified by:
hasUsedIndex
in interface IndexUseReporter
analyze
public void analyze(AnalyzeContextInfo contextInfo)
throws XPathException
- Description copied from interface:
Expression
- Statically analyze the expression and its subexpressions.
During the static analysis phase, the query engine can detect
unknown variables and some type errors.
- Specified by:
analyze
in interface Expression
- Overrides:
analyze
in class Function
- Throws:
XPathException
eval
public Sequence eval(Sequence contextSequence,
Item contextItem)
throws XPathException
- Description copied from interface:
Expression
- Evaluate the expression represented by this object.
Depending on the context in which this expression is executed,
either the context sequence, the context item or both of them may
be set. An implementing class should know how to handle this.
The general contract is as follows: if the
Dependency.CONTEXT_ITEM
bit is set in the bit field returned by Expression.getDependencies()
, the eval method will
be called once for every item in the context sequence. The contextItem
parameter will be set to the current item. Otherwise, the eval method will only be called
once for the whole context sequence and contextItem will be null.
eXist tries to process the entire context set in one, single step whenever
possible. Thus, most classes only expect context to contain a list of
nodes which represents the current context of the expression.
The position() function in XPath is an example for an expression,
which requires both, context sequence and context item to be set.
The context sequence might be a node set, a sequence of atomic values or a single
node or atomic value.
- Specified by:
eval
in interface Expression
- Specified by:
eval
in class Function
- Parameters:
contextSequence
- the current context sequence.contextItem
- a single item, taken from context. This defines the item,
the expression should work on.
- Throws:
XPathException
reset
public void reset()
- Description copied from interface:
CompiledXQuery
- Reset the compiled expression tree. Discard all
temporary expression results.
- Specified by:
reset
in interface CompiledXQuery
- Specified by:
reset
in interface CompiledExpression
- Overrides:
reset
in class PathExpr
resetState
public void resetState(boolean postOptimization)
- Description copied from interface:
Expression
- Called to inform an expression that it should reset to its initial state.
All cached data in the expression object should be dropped. For example,
the xmldb:document() function calls this method whenever the input document
set has changed.
- Specified by:
resetState
in interface Expression
- Overrides:
resetState
in class PathExpr
Copyright (C) Wolfgang Meier. All rights reserved.