com.icl.saxon.expr
Class RelationalExpression
java.lang.Object
|
+--com.icl.saxon.expr.Expression
|
+--com.icl.saxon.expr.BinaryExpression
|
+--com.icl.saxon.expr.RelationalExpression
- final class RelationalExpression
- extends BinaryExpression
Relational Expression: a boolean expression that compares two expressions
for equals, not-equals, greater-than or less-than.
Methods inherited from class com.icl.saxon.expr.Expression |
containsReferences, enumerate, evaluateAsNodeSet, evaluateAsNumber, evaluateAsString, getStaticContext, indent, isContextDocumentNodeSet, make, outputStringValue, setStaticContext, usesCurrent |
Methods inherited from class java.lang.Object |
, clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
RelationalExpression
public RelationalExpression()
- Default constructor
RelationalExpression
public RelationalExpression(Expression p1,
int op,
Expression p2)
- Create a relational expression identifying the two operands and the operator
- Parameters:
p1
- the left-hand operandop
- the operator, as a token returned by the Tokenizer (e.g. Tokenizer.LT)p2
- the right-hand operand
simplify
public Expression simplify()
throws XPathException
- Simplify an expression
- Overrides:
simplify
in class BinaryExpression
- Returns:
- the simplified expression
evaluate
public Value evaluate(Context c)
throws XPathException
- Evaluate the expression in a given context
- Overrides:
evaluate
in class Expression
- Parameters:
c
- the given context for evaluation- Returns:
- a BooleanValue representing the result of the numeric comparison of the two operands
evaluateAsBoolean
public boolean evaluateAsBoolean(Context c)
throws XPathException
- Evaluate the expression in a given context
- Overrides:
evaluateAsBoolean
in class Expression
- Parameters:
c
- the given context for evaluation- Returns:
- a boolean representing the result of the numeric comparison of the two operands
getDataType
public int getDataType()
- Determine the data type of the expression
- Overrides:
getDataType
in class Expression
- Returns:
- Value.BOOLEAN
reduce
public Expression reduce(int dependencies,
Context context)
throws XPathException
- Perform a partial evaluation of the expression, by eliminating specified dependencies
on the context.
- Overrides:
reduce
in class Expression
- Parameters:
dependencies
- The dependencies to be removedcontext
- The context to be used for the partial evaluation- Returns:
- a new expression that does not have any of the specified
dependencies