Notes

Java: Basics

Java is a General Purpose, Object Oriented Programming Language heavily used in Enterprise projects. Java Naming Conventions Following a standard naming convention would make a project codebase more readable and maintainable. Following are some of those standards used to name different things in Java. Classes and Interfaces names should be nouns first letter of each internal word should be capitalised must avoid acronyms and abbreviations Example: interface Bicycle class MountainBike implements Bicycle interface Sport class Football implements Sport Methods should be verbs first letter of the name should be lowercase first letter of each internal work should be uppercase example:

React Native Notes

Why web-view is bad? Less performent compared to native and native-like technologies Does not follow OS’s UI design pattern. Same design in both android and iOS Why React Native Big community. Makes development process easier as support can be expected from community when stuck Battle-tested framework. Used by companies like Facebook, Uber Eats, Discord, Skype. And invested by Shopify, Microsoft (despite having Xamarin) etc Cross-Platform. Write code once, and run it in three platform (Android, Web and iOS) React Native can’t beat Native App’s performence To understand this, we first gotta understand how React Native works internally.

Some Notes on Vim

Some notes on Vim window management, Tab Management and Other Stuffsa.. Window Management a window in Vim is the viewport for a buffer. following are a few useful window management command: Key Binding Action Command <C-w> o close all windows except the current one :on, :only <C-w q close focused window ZZ close focused window after saving changes ZQ close focused window without saving changes <C-w v split window vertically :vsplit <C-w s split window horizentally :split <C-w H/J/K/L move window to a direction <C-w h/j/k/l switch between windows <C-W> f split the window and edit filepath under cursor a/file/path.

Database

SQL Query Comments Database It’s a structured set of data which is structured in a certain way so that it can be scaled as and when required. SQL SQL is a query language for navigating through a database. SQL is used to create, read, modify and delete records from a database. Query A query, in SQL, is a way to make database engines understand user’s instructions.

Complete Ethical Hacking

Why Linux? it’s open-source free of cost environment for pen-testing good for development very light varities of distributions Network Commands in Linux ifconfig - shows interfaces and IP addresses corosponding to those interfaces MAC Addr - Unique addresses for every device in the world. used to communicate within local network IP Addr - used to communicate over internet. may change. Loopback Interface any traffic that computer sends to the loopback network is addressed to the same computer.

JavaScript Object Prototype

Object Object is Class. Almost everything in JavaScript is Object. All JavaScript values, except premitives, are object. Object Properties Named value in JavaScript objects are called properties. example: const person = { name: 'Jon', age: 23 } person.name // property person.age // property Accessing Object Properties Object properties can be accessed in multiple ways. person.name person["name"] const x = "name"; person[x] Object Methods An Object property is an Object method containing function definition.

Regular Expression

A regular expression is a group of characters or symbols which is used to find a specific pattern in a text. a string literal is the simplest possible regular expression. "str" would match str(s followed by t, followed by r). regular expression are generally case sensitive Meta Characters special characters. does not mean anything on their own. some meta character have different meaning when written inside square bracket meta char desc .

String in Rust

in the core language, Rust provides only one type of string: str, which is often seen in its borrowed form &str. Rust’s standard library provdes another type: String. this type is growable, owned and mutable. creating new String let s1 = "some string".to_string(); // create string from literals let mut s = String::new(); // creates an empty string let s2 = String::from("initial content"); // initialize with a value // strings are utf-8 encoded.

Vector in Rust

Vector: stores value of same type stores values next to each other in heap can store values dynamically creating a Vector when using associate function ::new(), one must use type annotation so that compiler have info about what kind of values to be stored in there // empty vector let v1: Vec<i32> = Vec::new(); // vecor with some initial values let v2: vec![1, 2, 3]; updating a vector Vector provide methods for running operations on any of its instances.

Make and Makefile

make is a tool responsible for generating binary and other non-source files of a program from the program’s source. make can be used to compile source code of any language. Features enables user to build and install software without knowing the details of that specific software compiles source files as needed. can relate to hot-reloading. make is also capable of installing and uninstalling packages. A Makefile contains instructions for make to run.