Skip to main content

Posts

Showing posts from January, 2017

Project Lombok : The Boilerplate Code Extractor

Lombok is a tool that generates code like getters, setters, constructors, equals, hashCode, toString for us in the same way that our IDE does. While IDE generates all these things in our source code file, Lombok generates them directly in the class file. So Lombok basically takes out all these things from your source code to bytecode so we don't need to write them in our source code which means less code in our source code file. And in this article, I am going to explain how Lombok can help us in removing this kind of boilerplate code. To understand it let's suppose we have an entity class Employee  and we want to use it to hold a single employee record. We can use it as a DTO or persistent entity or anything else we want but idea is that we want to use it to store  id , firstName , lastName  and salary  fields. For this requirement, we will need a simple Employee  POJO and according to General directions for creating Plain Old Java Object , Each variable in a POJO should be d

Java Cloning - Even Copy Constructors Are Not Sufficient

This is my third article on Java Cloning  series, In previous articles Java Cloning and Types of Cloning (Shallow and Deep) in Details with Example  and Java Cloning - Copy Constructor versus Cloning  I had discussed Java cloning in detail and explained every concept like what is cloning, how does it work, what are the necessary steps we need to follow to implement cloning, how to use Object.clone(), what is Shallow and Deep cloning, how to achieve cloning using Serialization and Copy constructors and advantages copy of copy constructors over Java cloning. If you have read those articles you can easily understand why it is good to use Copy constructors over cloning or Object.clone(). In this article, I am going to discuss why copy constructor are not sufficient? Yes, you are reading it right copy constructors are not sufficient by themselves, copy constructors are not polymorphic because constructors do not get inherited to the child class from the parent class. If we try to refer a

Java Cloning - Copy Constructor versus Cloning

In my previous article Java Cloning and Types of Cloning (Shallow and Deep) in Details with Example , I have discussed Java Cloning in details and answered questions about how we can use cloning to copy objects in Java, what are two different types of cloning (Shallow & Deep) and how we can implement both of them, if you haven’t read it please go ahead. In order to implement cloning, we need configure our classes to follow below steps Implement Cloneable interface in our class or its superclass or interface, Define clone() method which should handle CloneNotSupportedException (either throw or log), And in most cases from our clone() method we call the clone() method of the superclass. And super.clone() will call its super.clone() and chain will continue until call will reach to clone() method of the Object class which will create a field by field mem copy of our object and return it back. Like everything Cloning also comes with its advantages and disadvantages. However, Java cloni