Writing Scripts in Nashorn - Scripting in Java: Integrating with Groovy and JavaScript - page 111

Consider the code in Listing 4-8.
Listing 4-8. The Contents of the file prototype.js
// prototype.js
var point = {x: 10,
y: 20,
print: function() {
printf("(%d, %d)", this.x, this.y);
}
};
var coloredPoint = {color: "red",
print: function() {
printf("(%d, %d, %s)", this.x, this.y,
this.color);
}
};
// Set the point object as the prototype of the coloredPoint object
// That is, the coloredPoint object inherits from the point object.
Object.setPrototypeOf(coloredPoint, point);
print("After setting the prototype for coloredPoint...");
// Call the print() methods of both objects
point.print();
coloredPoint.print();
// Change the x and y values in the point object.
point.x = 100;
point.y = 200;
print("After setting the x and y properties for point...");
// Print the two points details again
point.print();
coloredPoint.print();
/* Call the toString() method that is defined in Object.prototype object and are
available in point and coloredPoint object through prototype chain.
*/
print(point.toString());
print(coloredPoint.toString());
// Print prototypes of objects