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Data Abstraction in Java
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Abstract Data Type
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+ Definition and Purpose of ADTs

  * Abstract Data Types (ADTs) are high-level data structures that encapsulate
    data and operations on that data. They provide a way to abstract and model
    real-world concepts or entities in software.
  * ADTs focus on the behavior and functionality of data rather than its
    implementation details, allowing programmers to work with data structures
    at a higher level of abstraction.

+ Benefits of Using ADTs

  * Modularity: ADTs promote modular design by encapsulating data and
    operations, making it easier to manage and maintain complex systems.
  * Code Reusability: ADTs can be reused across multiple projects or modules,
    saving development time and effort.
  * Security and Reliability: ADTs enforce data integrity and encapsulation,
    reducing the risk of errors and ensuring reliable and secure data
    manipulation.
  * Abstraction: ADTs provide a higher-level abstraction, allowing programmers
    to focus on the problem domain rather than low-level implementation
    details.

ADT in Java
===========
+ Defined as Java interfaces

  * Not all interfaces are ADTs

+ Collection of public interfaces are often known as a Java API (Application
  Programming Interface)
+ Implemented as Java class that implements the interface
+ Used in Java client classes
+ Complicated inheritance hierarchy of ADTs may occur

  * Interface inheritance
  * Implementation inheritance

.. note::

  This is in the ideal scenario. In practice, Java ADTs are often implemented
  directly as concrete classes if there are only a few implementations of the
  ADT.

Relationship to Data structures
===============================
+ ADTs are a high-level abstraction of data structures
+ Data structures are a low-level implementation of ADTs
+ In Java

  * ADTs are defined as interfaces
  * Data structures are defined as classes that implement the ADT interfaces