☕Java

코드잇 Bootcamp start 5.22.25 Java is an Object-Oriented Language

Overview 🥪

• JVM, JRE, JDK Explained
• Garbage collection (GC)
• Hello World - Java
• Thread
• Java File IO
• Thread
• Java Generic

Data Types and Variables

• Literals
• Primitive vs Reference types
• Local VS Class VS Instance variables
• Type Conversion in Java
• Unary Operators (단항 연산자)
• Data type operations & ranking
• Arrays in Java
• Immutable Objects

Basic Syntax & Info

• Switch statements in Java
• Short circuit evaluation
• Java packaging
• Java exception handling
• Java Annotation
• == and .equals
  • ==
    • checks if two variables point to the same object in memory
    • safe with enums because enums are constants
  • .equals
    • Compares the contents, not memory location
• Java Modifiers
  • Access modifiers (접근 제어자)
  • Non-Access modifiers (기타 제어자)
    • Final
• Java enum
• Java IO

Java Classes/Utilities

• String class
• Math class
• Wrapper class
• Scanner

Java Collection Framework(JCF)

Literally just a java version of data structures 🍟

• Collections
• ArrayList in Collections
• HashMap

OOP

Classes

• Classes & Instances
  • Classes & Instances
  • Fields
  • Methods
• Class vs Instance variables
• Class vs Instance methods
• Constructor & this

4 Fundamentals in OOP

• Inheritance in java
  • Composition
• Encapsulation
  • Immutable Objects
• Polymorphism in java
  • Method overloading
  • Method overriding
• Abstraction - Classes & Interfaces

SOLID

• Notion 링크
• SRP(Single Responsibility Principle)
• OCP (Open Closed Principle)
• LSP (Liskov’s Substitution Principle)
• ISP (Interface Segregation Principle)
  • 자바내부코드, spring 안들 보면 됨
  • in memory 저장 → repository
• DIP (Dependency Inversion Principle)

Lambda

• Lambda
• Functional Interfaces & Descriptor
• Method Reference

Stream

• Stream in Java

Design Patterns

• Factory design pattern