com.icl.saxon.expr
Class BooleanExpression
java.lang.Object
|
+--com.icl.saxon.expr.Expression
|
+--com.icl.saxon.expr.BinaryExpression
|
+--com.icl.saxon.expr.BooleanExpression
- class BooleanExpression
- extends BinaryExpression
Boolean expression: two booleans combined using AND or OR
Method Summary |
Value |
evaluate(Context c)
Evaluate an expression. |
boolean |
evaluateAsBoolean(Context c)
Evaluate an expression as a Boolean.
The result of x.evaluateAsBoolean(c) must be equivalent to x.evaluate(c).asBoolean();
but optimisations are possible when it is known that a boolean result is required,
especially in the case of a NodeSet. |
int |
getDataType()
Determine the data type of the expression |
Expression |
reduce(int dependencies,
Context context)
Perform a partial evaluation of the expression, by eliminating specified dependencies
on the context. |
Expression |
simplify()
Simplify an expression |
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 |
BooleanExpression
public BooleanExpression()
BooleanExpression
public BooleanExpression(Expression p1,
int operator,
Expression p2)
simplify
public Expression simplify()
throws XPathException
- Description copied from class:
BinaryExpression
- Simplify an expression
- Overrides:
simplify
in class BinaryExpression
- Following copied from class:
com.icl.saxon.expr.BinaryExpression
- Returns:
- the simplified expression
evaluate
public Value evaluate(Context c)
throws XPathException
- Description copied from class:
Expression
- Evaluate an expression.
- Overrides:
evaluate
in class Expression
- Following copied from class:
com.icl.saxon.expr.Expression
- Parameters:
context
- The context in which the expression is to be evaluated- Returns:
- the value of the expression, evaluated in the current context
evaluateAsBoolean
public boolean evaluateAsBoolean(Context c)
throws XPathException
- Description copied from class:
Expression
- Evaluate an expression as a Boolean.
The result of x.evaluateAsBoolean(c) must be equivalent to x.evaluate(c).asBoolean();
but optimisations are possible when it is known that a boolean result is required,
especially in the case of a NodeSet.
- Overrides:
evaluateAsBoolean
in class Expression
- Following copied from class:
com.icl.saxon.expr.Expression
- Parameters:
context
- The context in which the expression is to be evaluated- Returns:
- the value of the expression, evaluated in the current context
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