myTrace

표준기술 - J2EE(Enterprise Edition), J2SE(Standard Edition), J2ME(Micro Edition), 기타 java, javax package
준표준기술 - Library(functional), Framework(architectural)

Layered Architecture Style
1. Presentation Layer
- 표준 : JSP/Servlet
- 준표준 : MVC Framework (Struts + Webwork -> Struts2, Spring MVC)
2. Business Layer
- 표준 : EJB
- 준표준 : Container Framework (Spring Framework)
3. Data Persistence
- 표준 : JDBC
- 준표준 : Data Mapping Framework(iBatis),OR Mapping Framework(Hibernate)

Enterprise System
- 다수의 Request 발생 -> User 증가 -> web(JSP/Servlet)
- 다수의 Transaction 처리 -> Distribute 환경 -> EJB


Servlet/JSP 주요 객체

Class Name	추상화 대상	획득방법	생성/소멸 시점	데이터 공유
HttpServletRequest	client 요청 data	service method의 argument	요청 시 생성 응답 시 소멸	하나의 요청이 끝날 때까지 공유
HttpServletReponse	client 응답 data			-
ServletConfig	web.xml의 Init Parameter data (runtime 시 변경되지 않으며 유지보수 시 사용하기 위한 환경설정	getServletConfig()	Servlet과 동일	-
ServletContext	Web App 대표	getServletContext()	Server 시작/종료 시 생성/소멸	모든 사용자의 모든 요청 시 공유
Cookie	client side 상태 정보값	new Cookie	-	-
HttpSession	server side 상태 정보값	request.getSession()	프로그램에서 제어	현 사용자의 모든 요청 시 공유
RequestDispatcher	다른 JSP/Servlet 실행 목적	context.getRequestDispatcher	-	-

Tools
Ant : XML 형식의 빌드 파일을 이용하여 Source Code 입력 이외 모든 것 자동화
Junit : 자동화된 단위 테스트 구현
Log4j : XML 또는 properties 로그 정책 명시

Custom Tag (Tag Library)
1. Script Tag : <%--, <%, <%=, <%!, <%@
2. Action Tag : <jsp:useBean [ getProperty | setProperty | forward | include...]
3. Custom Tag : 개발자들이 직접 Action tag를 정의, 여러 JSP에서 반복되는 긴 자바코드 or HTML을 Tag로 대체

Tag Comparison
1. <%@ include file="b.jsp" %> : static include (compile 단계), dynamic include에 비해 성능이 아주 약간 더 빠름
2. <jsp:incude page="b.jsp" /> : dynamic include, 변경 시 유지보수 용이, 동일 Web Application 내의 file만 참조 가능 ( ServletContext - RequestDispatcher 이용)
3. <c:import url="b.jsp" /> : dynamic include, 모든 서버 내 file 참조 가능 (Network Program으로 변경)

page redirection
forward 방식 : ServletContext - RequestDispatcher - forward, url 변경이 없으며 새로고침 시 본래 페이지로 이동, 이전 상태 데이터 획득을 위해 Request 객체에 의해 데이터 공유 가능
redirect 방식 : HttpServletResponse - sendRedirect, 브라우저가 현재 페이지의 응답을 client측에 전달하고 다른 페이지로 이동, url 주소 변경 및 새로고침 시 이동한 페이지를 다시 로딩, 이전 상태 데이터 획득을 위해 request객체 대신 Cookie 또는 Session 이용해야 함

1991	The Green Project Begins MS DOS is the dominant operating system Cell phones weigh half a pound "Biosphere 2" project begins
1992	"Oak" is the language *7 Debuts "Duke" is featured in the Interface Johnny Carson signs off "The Tonight Show" on NBC
1993	The Green Project becomes FirstPerson Mosaic v1.0 is released "Cheers" ends an 11-year run
1994	WebRunner released — the first browser that supports moving objects and dynamic executable content The Apple QuickTake 100, the first consumer digital camera, goes on sale for less than $1,000 "Friends" debuts on NBC
1995	Java technology released to a select group on the Web site wicked.neato.org The San Jose Mercury News runs a front-page article about Java technology Name changed from "Oak" to "Java" Announced at Sun World -- Java technology is officially born
1996	The first JavaOne Developer Conference JDKtm 1.0 software is released Chess computer Deep Blue defeats Garry Kasparov for the first time "Dolly" the first cloned sheep is born
1997	Over 220,000 downloads of JDK 1.1 software occur in just three weeks JavaOne draws 8,000 attendees, becoming the world's largest developer conference Java Card 2.0 platform is unveiled 43% of U.S. families own a computer
1998	JDK 1.1 release downloads top 2 million Visa launches world's first smart card based on Java Card technology The Java Community Process (JCP) program formalized "Who Wants to Be a Millionaire?" premieres in the U.K
1999	Java 2 platform source code is released JavaOne draws 20,000 J2EE beta software is released "Star Wars Episode I: The Phantom Menace" released
2000	Over 400 Java User Groups are established worldwide Java Developer Connection program tops 1.5 million members Steve Jobs joins Scott McNealy on stage at JavaOne to announce a major commitment by Apple in support of Java technology Heavy Metal band Metallica sues Napster for copyright violations
2001	First international JavaOne conference in Yokohama Japan Over 1 million downloads of the Java Platform, Enterprise Edition (Java EE) SDK Google Inc. PageRank search algorithm patent awarded "The Lord of the Rings: The Fellowship of the Ring" is released
2002	J2EE SDK downloads reach 2 million 78% of executives view J2EE technology as the most effective platform for building and deploying Web services The Euro is introduced "The Osbournes" becomes a surprise hit on MTV
2003	Java technology runs in almost 550 million desktops Almost 75% of professional developers use Java programming language as their primary development language Commercial Voice-Over-Internet (VoiP) phone service begins "The Da Vinci Code" is published
2004	Java 2 Platform, Standard Edition 5 (Project Tiger) is released The Java technology-powered Mars Rover (Spirit) touches down on Mars Sun Java Studio Creator is launched
2005	Java technology celebrates its 10th birthday Approximately 4.5 million developers use Java technology Over 2.5 billion Java technology-enabled devices are available java.com bundles the Google Toolbar with the JRE download
2006	Rich Green announces at the JavaOne 2006 Conference that it's not a matter of when Sun will open source Java technology, but how. The NetBeans IDE 5.0 is released. Sun open-sourced Java EE components as the Glassfish Project to java.net. Java SE and ME initial components are released as open source. Pirates of the Caribbean: Dead Man's Chest is released.

from http://www.java.com/en/javahistory/timeline.jsp

about JAVA API
eclipse plug-in

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.ResultSet;
import java.util.Date;
import java.text.SimpleDateFormat;

public class compareTime
{
public static void main(String[] args)
{
try
{
Class.forName("oracle.jdbc.driver.OracleDriver");
System.out.println("Driver loading success");
}
catch (ClassNotFoundException e)
{
System.out.println("Driver loading fail");
}

try
{
Connection conn = DriverManager.getConnection
("jdbc:oracle:thin:@IP:PORT:SID","ID","PASSWORD");
System.out.println("Connection Success");
System.out.println("");

Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("select to_char(systimestamp, 'hh24:mi:ss:ff3') as time from dual");

System.out.println(getTime());

if (rs.next())
{
System.out.println("DB1 Time --> " + rs.getString("time"));
}

System.out.println(getTime());

conn.close();
System.out.println("");
System.out.println("Connection finished");
}
catch (SQLException sqle)
{
System.out.println("Connection fail");
}
catch (IllegalArgumentException ille)
{
System.out.println("IllegalArgument input");
}
}


private static String getTime()
{
SimpleDateFormat sdf = new SimpleDateFormat("kk:mm:ss:SS");

return "WAS1 Time --> " + sdf.format(new Date());
}
}