프로그래밍 언어/자바 웹

회원 정보 삭제하기

· 코딩마이데이

1. MemberServlet 클래스를 다음과 작성합니다. <a> 태그를 이용해 회원 정보를 삭제할 수 있는 링크를 추가합니다. 브라우저에서 삭제 요청도 전송하므로 if문에 else if문을 추가하여 삭제 기능을 추가합니다.

package sec02.ex02;

import jakarta.servlet.ServletException;
import jakarta.servlet.annotation.WebServlet;
import jakarta.servlet.http.HttpServlet;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Date;
import java.util.List;

@WebServlet("/member3")
public class MemberServlet extends HttpServlet {
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {		// TODO Auto-generated method stub
		doHandle(request, response);
	}
	
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {		// TODO Auto-generated method stub
		doHandle(request, response);
	}
	
	private void doHandle(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		request.setCharacterEncoding("utf-8");
		response.setContentType("text/html;charset=utf-8");
		MemberDAO dao = new MemberDAO();
		PrintWriter out = response.getWriter();
		String command = request.getParameter("command");
		
		if (command != null && command.equals("addMember"))
		{
			String _id=request.getParameter("id");
			 String _pwd=request.getParameter("pwd");
			 String _name=request.getParameter("name");
			 String _email=request.getParameter("email");
			 
			 MemberVO vo = new MemberVO();
			 vo.setId(_id);
			 vo.setPwd(_pwd);
			 vo.setName(_name);
			 vo.setEmail(_email);
			 dao.addMember(vo);
		} 
		 else if (command != null && command.equals("delMember"))
		 {
			 String id = request.getParameter("id");
			 dao.delMember(id);
		 }
		List<MemberVO> list = dao.listMembers();
	    out.print("<html><body>");
	    out.print("<table border=1><tr align='center' bgcolor='lightgreen'>");
	    out.print("<td>아이디</td><td>비밀번호</td><td>이름</td><td>이메일</td><td>가입일</td><td >삭제</td></tr>");
	    
	    for(int i = 0; i < list.size(); i++)
	    {
	    	MemberVO memberVO = (MemberVO) list.get(i);
	    	String id=memberVO.getId();
	 		String pwd = memberVO.getPwd();
	 		String name = memberVO.getName();
	 		String email =memberVO.getEmail();
	 		Date joinDate = memberVO.getJoinDate();
	 		out.print("<tr><td>"+id+"</td><td>"
	 			                +pwd+"</td><td>"
	 			                +name+"</td><td>"
	 			                +email+"</td><td>"
	 			                +joinDate+"</td><td>"
	 		                    +"<a href='/pro07/member3?command=delMember&id="+id+"'>삭제</a></td></tr>");
	    }
	    out.print("</table></body></html>");
	    out.print("<a href='/pro07/memberForm.html'>>새 회원 등록하기</a");
	}
}

 

2. MemberDAO 클래스를 다음과 같이 작성합니다. delete문의 첫 번째 "?"에 전달된 ID를 인자로 executeUpdate() 메서드를 호출합니다.

package sec02.ex02;

import java.sql.Connection;
import java.sql.Date;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.sql.DataSource;

public class MemberDAO {
	private PreparedStatement pstmt;
	private Connection con;
	private DataSource dataFactory;
	
	public MemberDAO() {
		try {
			Context ctx = new InitialContext();
			Context envContext = (Context) ctx.lookup("java:/comp/env");
			dataFactory = (DataSource) envContext.lookup("jdbc/oracle");
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	
	public List<MemberVO> listMembers() {
		List<MemberVO> list = new ArrayList<MemberVO>();
		try {
			// connDB();
			con = dataFactory.getConnection();
			String query = "select * from t_member ";
			System.out.println("prepareStatememt: " + query);
			pstmt = con.prepareStatement(query);
			ResultSet rs = pstmt.executeQuery();
			while (rs.next()) {
				String id = rs.getString("id");
				String pwd = rs.getString("pwd");
				String name = rs.getString("name");
				String email = rs.getString("email");
				Date joinDate = rs.getDate("joinDate");
				MemberVO vo = new MemberVO();
				vo.setId(id);
				vo.setPwd(pwd);
				vo.setName(name);
				vo.setEmail(email);
				vo.setJoinDate(joinDate);
				list.add(vo);
			}
			rs.close();
			pstmt.close();
			con.close();
		} catch (Exception e) {
			e.printStackTrace();
		}
		return list;
	}

	public void addMember(MemberVO memberVO) {
		try {
			con = dataFactory.getConnection();
			String id = memberVO.getId();
			String pwd = memberVO.getPwd();
			String name = memberVO.getName();
			String email = memberVO.getEmail();
			String query = "insert into t_member";
			query += " (id,pwd,name,email)";
			query += " values(?,?,?,?)";
			System.out.println("prepareStatememt: " + query);
			pstmt = con.prepareStatement(query);
			pstmt.setString(1, id);
			pstmt.setString(2, pwd);
			pstmt.setString(3, name);
			pstmt.setString(4, email);
			pstmt.executeUpdate();
			pstmt.close();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	
	public void delMember(String id)
	{
		try {
			con = dataFactory.getConnection();
			
			String query = "delete from t_member" + " where id=?";
			System.out.println("prepareStatement:" + query);
			pstmt = con.prepareStatement(query);
			pstmt.setString(1, id);
			pstmt.executeUpdate();
			pstmt.close();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
}

 

3. http://localhost:8090/member3로 요청한 후 삭제를 클릭합니다.

삭제를 클릭해 회원 정보 삭제

 

4. 회원 정보를 삭제한 후 남은 회원 정보가 다시 출력됩니다.

삭제 후 회원 정보 출력

 

서블릿에서 데이터베이스와 연동하는 작업은 크게 CRUD(Create, Read, Update, Delete) 작업으로 나눌 수 있습니다.