[JSP/Servlet] 라이프 사이클

서블릿 라이프 사이클

 서블릿은 최초 호출시에 메모리에 로딩되고, 두 번째 이후 부터는 메모리에 로딩된 서블릿을 호출하기 때문에 수행 속도가 빠르다.

 

 

package Unit01;

import java.io.IOException;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class LifeCycle
 */
@WebServlet("/LifeCycle")
public class LifeCycle extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
	int initCount = 1;
	int destroyCount = 1;
	int doGetCount = 1;
    /**
     * @see HttpServlet#HttpServlet()
     */
    public LifeCycle() {
        super();
        // TODO Auto-generated constructor stub
    }
    
    @Override
    public void init(ServletConfig config) throws ServletException {
    	super.init(config);
    	
    	System.out.println("init() 메소드는 최초 서블렛 생성시에만 호출됨 : " + initCount++);
    }
    
    

	@Override
	public void destroy() {
		// TODO Auto-generated method stub
		super.destroy();
		
		System.out.println("destroy() 메소드는 WAS 종료시에만 호출됨 : " + destroyCount++);
	}


	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		System.out.println("doGet() 메소드가 요청될 때 마다 호출됨 : " + doGetCount++);
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}

}

 

 

 

웹페이지를 새로고침할 때 마다 doGet 메소드가 요청되는 것을 볼 수 있다.