week1. Introduction
본 포스트의 요약은 제가 현재 학교 수업으로 듣고 있는 객체지향 프로그래밍 및 실습이란 과목입니다.
현 과목에서 저희 수업은 java 언어를 통하여 객체지향 프로그래밍을 배우고 있습니다.
영어로 수업을 배우고 있어서, 모든 요약은 거의 영어로 됩니다.
제 스스로 복습을 위한 정리 공간이지만, 이 글을 읽는 분에게도 도움이 되었으면 합니다.
◆ Java programming Language
- Simple
- Safe
- Paltform-independent("write once, run anywhere")
- Rich library(Package)
- Designed for the internet
◆ The Structure of a Simple Program
: Class Declaration
- Class : fundamental building blocks of Java Program
public class HelloPrinter
- every source can contain at most one public class
- The name if the public class must match the name of the file containing the class
Class HelloPrinter must be contained in a file named HelloPrinter.java
: main Method
- Every Java application contains a class with a main method
declares a main method
pubilic static void main(String[] args)
{
...
}
: Comments
- The first line inside the main method is a comment
: Statements
- The body of the main method contains statements inside the curly bracket({}).
- Each statement end in a semicolon(;).
- Statements are executed one by one
: Method Call
- System.out.println("Hello, world!"); is a method call
=> System.out ( method is invoked on this object): Object
=> println() (name of method) : Method
=> "Hello,World!" : Parameters
: String
- A sequence of characters enclosed in double quotation marks ("")
◆ Editing a Java Program
- Java is case-sensitive : distinguish between upper- and lowercase letters
- Lay out your program so that they are easy to read
◆ Compiling and Running a Java Program
- source code ---[ Java Compiler ]---> class files contain instruction for the Java virtual machine
- class file has extension .class
◆ Errors
- Compile-time error : A violation of the programming language rules that is detected by the compiler
ex. System.ou.println("Hello,world!"); -> Syntax error
- Run-time error : Causes the program to take an action that the programmer did not intend
ex. System.out.println("Hello,world!"); System.out.println(1/0); -> Logic error
◆ Algorithms
- A sequence of steps that is : *umambiguougs, *executable, *terminating
◆ Pseudocode : An informal description of an algorithm
10주 넘게 수업나갔는데... 이제요약시작 ;
뭐든지 기본 개념이 제일 중요합니다 :)