/**
* Finds the node causing a NPE for diadic operators.
* @param xrt the RuntimeException
* @param node the parent node
* @param left the left argument
* @param right the right argument
* @return the left, right or parent node
*/
protected JexlNode findNullOperand(RuntimeException xrt, JexlNode node, Object left, Object right) {
if (xrt instanceof ArithmeticException
&& JexlException.NULL_OPERAND == xrt.getMessage()) {
if (left == null)
{
return node.jjtGetChild(0);
}
if (right == null)
{
return node.jjtGetChild(1);
}
}
return node;
}
/**
* Resolves a namespace, eventually allocating an instance using context as constructor argument.
* The lifetime of such instances span the current expression or script evaluation.
*
* @param prefix the prefix name (may be null for global namespace)
* @param node the AST node
* @return the namespace instance
*/
protected Object resolveNamespace(String prefix, JexlNode node) {
Object namespace = null;
/**
* Interpret the given script/expression.
* <p>
* If the underlying JEXL engine is silent, errors will be logged through its logger as info.
* </p>
* @param node the script or expression to interpret.
* @return the result of the interpretation.
* @throws JexlException if any error occurs during interpretation.
*/
public Object interpret(JexlNode node) {
try
{
return node.jjtAccept(this, null);
}
catch (JexlException.Return xreturn)
{
Object value = xreturn.getValue();
return value;
}
catch (JexlException xjexl)
{
if (silent)
{
logger.warn(xjexl.getMessage(), xjexl.getCause());
return null;
}
throw xjexl;
}
readonlyly
{
functors = null;
parameters = null;
registers = null;
}
}
