Writing Scripts in Nashorn - Scripting in Java: Integrating with Groovy and JavaScript - page 127

Listing 4-18. Adding Missing Property and Method Hooks
// missingprops.js
var point = {x:10, y:20};
// Add no such property and no such method hooks
Object.prototype.__noSuchProperty__ = function (prop) {
throw Error("No such property: " + prop);
};
Object.prototype.__noSuchMethod__ = function () {
var desc = arguments[0] + "(";
if (arguments.length > 1) {
desc += arguments[1];
}
for (var i = 2; i < arguments.length; i++) {
desc += ", " + arguments[i];
}
desc += ")";
throw Error("No matching method found: " + desc);
};
// Try accessing point.z. Will throw an Error.
try {
var z = point.z;
}
catch(e) {
print(e.message);
}
// try calling a ono-existent method named dustance
try {
point.distance(10, 20);
}
catch(e) {
print(e.message);
}
No such property: z
No matching method found: distance(10, 20)