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Showing posts from October, 2020

ACTIVATION STACK

  ACTIVATION STACK: The activation stack is where the run time environment of the program keeps track of all the functions that have been called. The activation stack records all the necessary information about a function call, including parameters, local variable, return values, location currently being executed in the function, etc. As one function call a function, which in turn calls yet another function, all of this information is stored in the activation stack  A Stack refers to a method of placing one thing on top of another. In a cafeteria, the clean trays are placed in a stack, one after the other, and the most recently cleaned tray is on the top of the stack, waiting for your use. OF course, this means the tray that was cleaned longest ago is on the bottom of the stack. As your program calls more and more "functions" the computer keeps track of this information in an "Activation Stack" (a list of all functions in the order they were called, wherein the func...

JAVA BEANS

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  JavaBean A JavaBean is a Java class that should follow the following conventions: It should have a no-arg constructor. It should be Serializable. It should provide methods to set and get the values of the properties, known as getter and setter methods. Why use JavaBean? According to Java white paper, it is a reusable software component. A bean encapsulates many objects into one object so that we can access this object from multiple places. Moreover, it provides easy maintenance. Simple example of JavaBean class //Employee.java      package mypack;   public class Employee implements java.io.Serializable{   private int id;   private String name;   public Employee(){}   public void setId(int id){this.id=id;}   public int getId(){return id;}   public void setName(String name){this.name=name;}   public String getName(){return name;}   }   How to access the JavaBean c...

Features of OOPS in Python

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OBJECT ORIENTED PROGRAMMING Python is a multi-paradigm programming language. It supports different programming approaches. One of the popular approaches to solve a programming problem is by creating objects. This is known as Object-Oriented Programming (OOP). OBJECT: An object has two characteristics: attributes behavior Let's take an example: A parrot is can be an object, as it has the following properties: name, age, color as attributes singing, dancing as behavior The concept of OOP in Python focuses on creating reusable code. This concept is also known as DRY (Don't Repeat Yourself). CLASS: A class is a blueprint for the object. We can think of class as a sketch of a parrot with labels. It contains all the details about the name, colors, size etc. Based on these descriptions, we can study about the parrot. Here, a parrot is an object. The example for class of parrot can be : class Parrot:     pass Here, we use the class keyword to define an empty class Parrot. From class, ...

DIFFERENCE BETWEEN PROCEDURAL AND OBJECT ORIENTED PROGRAMMING

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PROCEDURAL PROGRAMMING: Procedural programming can be defined as a programming model which is derived from structured programming, based upon the concept of calling procedure. Procedures, also known as routines, Subroutines, or functions, simply consist of a series of computational steps to be carried out. During a program's execution, any given procedure might be called at any point, including by other procedures or itself  1.In procedural programming, the program is divided into small parts called functions. 2.Procedural programming follows a top-down approach. 3.There is no access specifier in procedural programming. 4.Adding new data and function are not easy. 5.Procedural programming does not have any proper way of hiding data so it is less secure. 6.In procedural programming, overloading is not possible. 7.In procedural programming, the function is more important than data. 8.Procedural programming is based on an unreal world. Examples: C, FORTRAN, Pascal, Basic, etc. LANGU...

GOOGLE DORKS

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WHAT IS GOOGLE DORKS? It is basically a search string that uses the advanced search query to find information that is not easily available on the website. That is most of the time when you search using the google tab it gives you the relevant things to the word you search. For Eg: If you search shoe it shows the availability of shoes in online stores, the definition of the shoe, etc. But when you search using Google Dorks it gives an exact result like the availability of shoes in Flipkart. It is also regarded as illegal google hacking activity which hackers often uses fro purpose such as cyber terrorism and cyber theft Can Google be used by Hackers to hack websites? People often take Google as just a search engine used to find text, images, videos, and news. However, in the information world, it has a very vast role. Google can be also be used as very useful hacking tool. we cannot hack websites directly using Google. But it's tremendous web crawling capabilities can be of great he...

Difference Between VLAN and Subnetting

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  VLAN: 1.VLAN - VIRTUAL AREA NETWORK 2.VLAN is any broadcast domain that is partitioned and isolated in a computer network at the data link layer. 3.VLAN work by applying tags to the network frames and handling these tags in networking systems 4.creating the appearance and functionality of network traffic that is physically on a single network but acts as if it is split between separate networks 5.In this way Vlan can keep network application separate despite being connected to same physical network and without requiring multiple sets of cabling andd networking devices to be deployed EXAMPLE: Here in the above figure, there is a router connected to three switches and each switch has many systems connected to many systems. So all End devices are connected to the same Local Area Network. So in this Network, The End device of any switch can access the data from every end device in the network. Let us assume a scenario, You are a network administrator in a company called XYZ, you have...