/**
* Return the Java value corresponding to an XPath result.
*
* @param xo the XPath type
* @return the corresponding Java value per the JSTL mapping rules
* @throws TransformerException if there was a problem converting the type
*/
static Object coerceToJava(XObject xo) throws TransformerException {
if (xo instanceof XBoolean) {
return xo.bool();
} else if (xo instanceof XNumber) {
return xo.num();
} else if (xo instanceof XString) {
return xo.str();
} else if (xo instanceof XNodeSet) {
NodeList nodes = xo.nodelist();
// if there is only one node in the nodeset return it rather than the list
if (nodes.getLength() == 1) {
return nodes.item(0);
} else {
return nodes;
}
} else {
// unexpected result type
throw new AssertionError();
}
}
/**
* Apply the operation to two operands, and return the result.
*
* @param right non-null reference to the evaluated right operand.
* @return non-null reference to the XObject that represents the result of the operation.
* @throws javax.xml.transform.TransformerException
*/
public XObject operate(XObject right) throws javax.xml.transform.TransformerException {
if (XObject.CLASS_BOOLEAN == right.getType()) return right;
else return right.bool() ? XBoolean.S_TRUE : XBoolean.S_FALSE;
}