net.sf.joost.grammar.tree
Class RootTree
java.lang.Object
net.sf.joost.grammar.Tree
net.sf.joost.grammar.tree.RootTree
- All Implemented Interfaces:
- Cloneable
public final class RootTree
- extends Tree
Objects of RootTree represent root nodes in the syntax tree of a pattern or
an STXPath expression.
- Version:
- $Revision: 1.2 $ $Date: 2007/05/20 18:00:44 $
- Author:
- Oliver Becker
Fields inherited from class net.sf.joost.grammar.Tree |
ADD, AND, ATTR, ATTR_LOCAL_WILDCARD, ATTR_URI_WILDCARD, ATTR_WILDCARD, AVT, CDATA_TEST, CHILD, COMMENT_TEST, DDOT, DESC, DIV, DOT, EQ, FUNCTION, GE, GT, LE, left, LIST, lName, LOCAL_WILDCARD, LT, MOD, MULT, NAME_TEST, NE, NODE_TEST, NUMBER, OR, PI_TEST, PREDICATE, right, ROOT, SEQ, STRING, SUB, TEXT_TEST, type, UNION, uri, URI_WILDCARD, value, VALUE, VAR, WILDCARD |
Method Summary |
Value |
evaluate(Context context,
int top)
Evaluates the current Tree if it represents an expression. |
boolean |
isConstant()
|
boolean |
matches(Context context,
int top,
boolean setPosition)
Determines if the event stack matches the pattern represented
by this Tree object. |
RootTree
public RootTree(Tree left)
RootTree
public RootTree()
matches
public boolean matches(Context context,
int top,
boolean setPosition)
throws SAXException
- Description copied from class:
Tree
- Determines if the event stack matches the pattern represented
by this Tree object.
- Overrides:
matches
in class Tree
- Parameters:
context
- the Context objecttop
- the part of the stack to be considered while matching
(the upper most element is at position top-1)setPosition
- true
if the context position
(Context.position
) should be set in case the
event stack matches this pattern
- Returns:
true
if the stack matches the pattern represented
by this Tree.
- Throws:
SAXException
evaluate
public Value evaluate(Context context,
int top)
throws SAXException
- Description copied from class:
Tree
- Evaluates the current Tree if it represents an expression.
- Overrides:
evaluate
in class Tree
- Parameters:
context
- the current Contexttop
- the part of the stack to be considered for the evaluation
(the upper most element is at position top-1)
- Returns:
- a new computed Value object containing the result
- Throws:
SAXException
isConstant
public boolean isConstant()
- Overrides:
isConstant
in class Tree
- Returns:
- whether the expression represented by this tree is constant