4, so that OEMs can use or modify the source code on their smartphones.Build a Shed Under the Stairs. The AOSP version of Android 12 was released a few weeks earlier on Oct. 19, 2021, so anyone with a Pixel 3 or newer model can install the new operating system with an over-the-air update. Android 12 was released to the Google Pixel devices on Oct.
You need not worry whether the motherboard is a 4-layer or 6-layer board, whether the hard disk has 4 or 6 plates 3 inches or 5 inches in diameter, whether the RAM is made in Japan or Korea, and so on. You turn on the power, and the PC runs. Stack Wood Under a Seat.Suppose that you want to assemble your own PC, you go to a hardware store and pick up a motherboard, a processor, some RAMs, a hard disk, a casing, a power supply, and put them together. This hideaway functions as a tool shed that can handle taller equipment, and it doesnt take up any of your precious yard space.
Hide Object Borders In Disc Cover 3 Software Application By
Functions are often not reusable. The programs are made up of functions. However, for each new application, we have to re-invent the wheels and write the program from scratch.Why re-invent the wheels? Traditional Procedural-Oriented languagesCan we do this in traditional procedural-oriented programming language such as C, Fortran, Cobol, or Pascal?Traditional procedural-oriented languages (such as C and Pascal) suffer some notable drawbacks in creating reusable software components: Since the advent of computer 60 years ago, we have written tons and tons of programs. The components are reusable, e.g., a wheel can be used in many cars (of the same specifications).Hardware, such as computers and cars, are assembled from parts, which are reusable components.How about software? Can you "assemble" a software application by picking a routine here, a routine there, and expect the program to run? The answer is obviously no! Unlike hardware, it is very difficult to "assemble" an application from software components. Intellectual property crime can cover a wide range of activities.Similarly, a car is assembled from parts and components, such as chassis, doors, engine, wheels, brake, and transmission.
(Imagine using assembly codes, which is a very low level code, to write a computer soccer game. For example, C programs uses constructs such as if-else, for-loop, array, function, pointer, which are low-level and hard to abstract real problems such as a Customer Relationship Management (CRM) system or a computer soccer game. The procedural languages are not suitable of high-level abstraction for solving real life problems. In other words, functions are not well-encapsulated as a self-contained reusable unit.
Software faults could affect other programs running in computers.The task force proposed to make software behave like hardware OBJECT. Software procedures were often non-sharable and not reusable. (Hardware can share and reuse! Hardware faults are isolated!) Hardware components could be applied to various products, and their integrity normally did not affect other products. More than 80% of the software budget went to maintenance (only the remaining 20% for new software development). 80% of the budget went to the software (while the remaining 20% to the hardware).
In other words, OOP combines the data structures and algorithms of a software entity inside the same box. Since the class is well-encapsulated (compared with the function), it is easier to reuse these classes. The basic unit of OOP is a class, which encapsulates both the static attributes and dynamic behaviors within a "box", and specifies the public interface for using these boxes. Object-Oriented Programming LanguagesObject-oriented programming (OOP) languages are designed to overcome these problems.
The OOP languages (such as Java, C++, C#) let you think in the problem space, and use software objects to represent and abstract entities of the problem space to solve the problem.As an example, suppose you wish to write a computer soccer games (which I consider as a complex application). Memory bits and bytes, array, decision, loop) rather than thinking in terms of the problem you are trying to solve. The traditional procedural language (such as C and Pascal) forces you to think in terms of the structure of the computer (e.g.
Ease in software design as you could think in the problem space rather than the machine's bits and bytes. You figure out all the objects by putting all the data and operations that describe the user's interaction with the data.Object-Oriented technology has many benefits: You need to first figure out all the functions and then think about how to represent data.The object-oriented languages focus on components that the user perceives, with objects as the basic unit. Benefits of OOPThe procedural-oriented languages focus on procedures, with function as the basic unit. Player: attributes include name, number, location in the field, and etc operations include run, jump, kick-the-ball, and etc.Most importantly, some of these classes (such as Ball and Audience) can be reused in another application, e.g., computer basketball game, with little or no modification. But using OOP languages, you can easily model the program accordingly to the "real things" appear in the soccer games.
In other words, an instance is an instantiation of a class. In other words, a class is a blueprint, template, or prototype that defines and describes the static attributes and dynamic behaviors common to all objects of the same kind.Instance: An instance is a realization of a particular item of a class. The fastest and safest way of developing a new application is to reuse existing codes - fully tested and proven codes.Class: A class is a definition of objects of the same kind. Reusable software: you don't need to keep re-inventing the wheels and re-write the same functions for different situations. Ease in software maintenance: object-oriented software are easier to understand, therefore easier to test, debug, and maintain. Ease in design leads to more productive software development.
Classname (or identifier): identifies the class. A Class is a 3-Compartment Box encapsulating Data and FunctionsA class can be visualized as a three-compartment box, as illustrated: But it is often used quite loosely, which may refer to a class or an instance. For example, you can define a class called " Student" and create three instances of the class " Student" for " Peter", " Paul" and " Pauline".The term " object" usually refers to instance.
An instance (object) is also represented as a 3-compartment box, with instance name shown as instanceName:Classname and underlined. Classname is shown in bold and centralized. A class is represented as a 3-compartment box, containing name, data members (variables), and member functions, respectively. Member Functions (or methods, behaviors, operations): contains the dynamic operations of the class.In other words, a class encapsulates the static attributes (data) and dynamic behaviors (operations that operate on the data) in a box.Class Members: The data members and member functions are collectively called class members.The followings figure shows a few examples of classes:The following figure shows two instances of the class Student, identified as " paul" and " peter".Unified Modeling Language (UML) Class and Instance Diagrams: The above class diagrams are drawn according to the UML notations.
There are two sections in the class declaration: private and public, which will be explained later.
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