Programming

Programming编程是一项需要深入学习和实践的技能，它能够帮助人们更好地利用计算机技术来解决实际问题。

Programming

Programming languages

Java

Platforms

SE (Standard Edition)

Java Core

Fundamentals

Variables

Class variables

Local variables

Methods

Overriding methods

Overloaded methods

Constructors

Data types

By mutability

Mutable

Immutable

By category

Primitives

Integer

Floating-point

Char

Boolean

Complex

String

Wrapper classes

For primitive types

Operators

Increment / decrement

Relational

Input / output

Control Flow

Block scope

Conditional statements

If

Switch statement

Ternary operator

int x = a.compare(b) ? a : b

Loops

For

While

Do-while

For-each

Type conversion

Casting

Upcasting

Animal a = new Dog();

Downcasting

Dog a = (Dog) new Animal();

Arrays

Multidimensional

Classes

Ordinary classes

Abstract classes

Inner classes

Anonymous Inner Classes

Enum classes

Interfaces

Java 8 introduced ability to have default implementation of methods declared in interfaces

Iterable

Iterator

Comparator

Comparable

Marker Interfaces

EventListener

Cloneable

Serializable

Externalizable

Generics

By parameter type

Any type

Bounded type

By category

Generic classes

Generic methods

Exceptions

Type

Checked

Custom

Unchecked

Handling

Try-catch (try-catch-finally)

Try-with-resources

Throws

Propagates exception to caller. Caller propagates further or handles via try-catch

Throw

Packages

JAR files

Autoboxing

Concerns wrapper classes

Access Levels

Package (default)

Public

Private

Protected

Keywords

[access modifiers]

static

void

final

synchronized

this

super

extends

implements

assert

import

transient

fields marked with "transient" keyword are excluded during serialization

I/O

Bytes (file) I/O

Character I/O

java.util.Scanner

Reader

Writer

Primitives I/O

DataInputStream

DataOutputStream

Buffered I/O

Buffered................

Java Object I/O (serialize/deserialize)

Network I/O

URLConnection

Database I/O

Console I/O

Concurrency

Thread (class)

Runnable (interface)

Reflection

Serialization

RMI (remote method invocation)

Annotation

Lambda expressions

Since Java 8

Standard Java Packages

Collections Framework

Implementations

Set

stores non-duplicating (unique) items

HashSet

TreeSet

LindedHashSet

List

ArrayList

LinkedList

Queue

Deque

Map

stores key-value pairs

HashMap

ConcurrentHashMap

TreeMap

LinkedHashMap

Iteration mechanisms

Iterator (interface)

Iterable (interface)

forEach (method)

- since Java 8 - Iterable interface contains default implementation

JDBC

API documentation

Javadoc

EE (Enterprise Edition)

Applets (deprecated)

Servlets

JSP

JSF

EJB

JMS

Third-party libraries

Apache Commons

Apache.commons.io.FileUtils

JVM

Garbage Collection

Tools, Technologies, Frameworks

Server

Java Servlet Containers

Apache Tomcat

In general, the Apache HTTP server is just a plain old web server designed to serve static web pages. There are plenty of modules which can be installed to enhance Apache's abilities so that it can serve dynamic webpages using various technologies such as PHP, CGI or whatever, but the core of Apache is just a plain old HTTP server. Tomcat, on the other hand, is specifically designed from the ground-up to serve as a Java Servlet engine. It's primary purpose is to implement the Java Servlet API and execute Java servlets for the purpose of building dynamic websites. Tomcat can also be used as a regular HTTP server that serves static pages, but that is not its primary purpose. (Also, Tomcat is allegedly slower than Apache httpd when it comes to serving static pages.) The two technologies can be used together through a connector module called mod_jk. This will allow you to use the Apache HTTP server to serve regular static webpages, and the Tomcat Servlet engine to execute servlets.

Java Application Servers

Web server + Java Servlet Container

Glassfish

WildFly

Testing

JUnit

ORM

Hibernate

Build Tools

Maven

Web Framework

Spring MVC

Code Analysis

FindBugs

IDE

IDEA IntelliJ

Core Features

Abstraction

Encapsulation

Inheritance

Polymorphism

JavaScript

HTML

CSS

Algorithms and data structures

Patterns

Testing

Server Technologies

Web servers

Apache

nginx

Version Control System

Centralized

Distributed

Git

Basic console commands

git init

creates a Git directory (.git) in current directory

git status

shows current Git status

git branch

lists Git branches

git branch xxx

creates xxx branch

git checkout xxx

switches to xxx branch

git checkout -b xxx

creates xxx branch and switches to it

git add xxx

adds modified files xxx to commit queue

git commit -m "xxx"

commits modifications with "xxx" comment

git merge xxx

merges current branch with xxx branch

git remote add origin xxx://xxxx/xxx.git

registers xxx://xxxx/xxx.git as the remote Git repository

git push -u origin master

pushes master branch files to remote branch (origin)

git pull origin master

pulls changes from remote repo (origin) to local repo (master branch)

Git hosting

github.com

Basic repo operations

Fork

copy repository to your own repository

Clone

download entire repository with .git directory

Download as ZIP file

download repository as ZIP file without .git directory

Pull request

request somebody to pull changes from you back to their repository

Databases

Relational

MySQL

NoSQL

Unix

Networks

Fundamentals

Protocols

TCP/IP

UDP

HTTP

HTTPS

Identifiers

IP address

IPv4

IPv6

Ports

Sockets

Socket address

IP address + port

StringTokenizer

Versioning

Means marking different versions of classes with serialVersionUID

java.nio.file.Files

StringBuffer

StringBuilder