For a computer novice, data hiding and data encapsulation might mean the same thing. However, there are major differences between the two concepts.
Data encapsulation and data hiding fall under the category of object–oriented programming and can be used in different programming languages like C, C++, and others. They are considered to be the two main concepts of object–oriented programming.
Data encapsulation and data hiding both involve objects (classified as values, data, structures, or functions), classes (collection of data and methods), the computer code, and methods.
Data encapsulation is the process of combining and assembling elements in order to create a new entity and the wrapping of private data into a class. The encapsulation involves the implementation of data and method. Data with internal methods are secured into a capsule, while the methods are used to access the data inside it. In this manner, the assembly and grouping of all data and requirements inside a capsule make it independent for an object to function together.
The encapsulation also involves the way the class is hidden from users and how the process can be reversed by unlocking the capsule using methods.
In data encapsulation, the capsule and the object inside it can be classified as either private or public, unless specified or programmed by the programmer.
On the other hand, data hiding is the process of hiding the details of an object or function. It is also a potent technique in programming that results in data security and less data complexity.
One of the manifestations of data hiding is that it is used as a method of hiding information inside a computer code after the code is broken down and hidden from the object. All objects in the state of data hiding are in isolated units, which is the main concept of object-oriented programming.
The data inside is classified as private or non-accessible from other objects, classes, and API’s in the system. The data appear as invisible to outsiders – whether objects, other classes, or users.
Data encapsulation is one of the chief mechanisms of data hiding. Data hiding works by nesting the data or arranging it into capsules.
Data hiding has many uses, including:
- Security purposes and data protection from misuse and unauthorized access;
- Utilizing changing functions to move with difficulty from the outside;
- Hiding the data from unauthorized access or use by suspicious users, especially computer hackers who try to manipulate sensitive data or the program;
- Hiding the physical storage layout for data and avoiding linking to incorrect data. (If a programmer does link to said data, the program will display an error to protect the content.)
Data hiding is usually used or executed on volatile and sensitive data. These types of data are essential in running the program efficiently and smoothly. If these types of data are manipulated in some way, any user of the program will not be able to use the application properly. The programmer will have to rewrite the program and fix the errors before further use.
- Data encapsulation is a process, while data hiding is both a process and a technique. They both share the category of object-oriented programming.
- The data in data encapsulation is either public or private, while the data in data hiding is private and non-accessible.
- Data encapsulation is one of the mechanisms of data hiding.
- Data encapsulation’s concern is for consolidation, which is related to data’s hiding goal of reaching less complexity in data. On the other hand, data hiding encompasses not only less data complexity, but also data protection and security.
- The focus of data encapsulation is on the data inside the capsule, while data hiding is concerned with restrictions on terms of access and use.