오늘 배운 것

• Todo 만들기

Todo bean 만들기

package todoApp.model;

import java.time.LocalDate;

public class Todo {
	private Long id; // int보다 큰 숫자까지 표현
	private String title; // 할일 제목
	private String username; // 유저 이름
	private String description; // 내용
	private LocalDate targetDate; // 목표날짜 예) 2012-12-12
	private boolean status; // 현재 상태(할일을 진행 또는 완료)
	
	protected Todo() {}

	public Todo(Long id, String title, String username, String description, LocalDate targetDate, boolean status) {
		super();
		this.id = id;
		this.title = title;
		this.username = username;
		this.description = description;
		this.targetDate = targetDate;
		this.status = status;
	}

	public Long getId() {
		return id;
	}

	public void setId(Long id) {
		this.id = id;
	}

	public String getTitle() {
		return title;
	}

	public void setTitle(String title) {
		this.title = title;
	}

	public String getUsername() {
		return username;
	}

	public void setUsername(String username) {
		this.username = username;
	}

	public String getDescription() {
		return description;
	}

	public void setDescription(String description) {
		this.description = description;
	}

	public LocalDate getTargetDate() {
		return targetDate;
	}

	public void setTargetDate(LocalDate targetDate) {
		this.targetDate = targetDate;
	}

	public boolean isStatus() {
		return status;
	}

	public void setStatus(boolean status) {
		this.status = status;
	}
	// 해시코드와 equals를 id로 자동완성 => 객체를 id로 구별

	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + ((id == null) ? 0 : id.hashCode());
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		Todo other = (Todo) obj;
		if (id == null) {
			if (other.id != null)
				return false;
		} else if (!id.equals(other.id))
			return false;
		return true;
	}

	@Override
	public String toString() {
		return "Todo [id=" + id + ", title=" + title + ", username=" + username + ", description=" + description
				+ ", targetDate=" + targetDate + ", status=" + status + "]";
	}
}

• interface로 만든다음 implement로 구현하기

package todoApp.dao;
// interface dao로 이것을 구현해서 기능을 완성시키게 함

import java.util.List;

import todoApp.model.Todo;

public interface TodoDao {
	// Create 입력 => 할 일을 DB에 입력
	void insertTodo(Todo todo);
	// Read id로 할일을 검색
	Todo selectTodo(long todoId);
	// Read 모든 할일을 검색
	List<Todo> selectAllTodos();
	// Delete 할일을 삭제(id로)
	boolean deleteTodo(long todoId);
	// Update 할일을 업데이트
	boolean updateTodo(Todo todo);
}

interface의 기능 구현하기

• 기본 기능인 Create Read Update Delete 구현하기

package todoApp.dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.time.LocalDate;
import java.util.ArrayList;
import java.util.List;

import todoApp.model.Todo;
import todoApp.utils.JDBCUtils;

public class TodoDaoImpl implements TodoDao {
// DB연결하고 각 기능에 맞게 작업, DB todos테이블에 CRUD 작업
	@Override
	public void insertTodo(Todo todo) {
		String INSERT_USER_SQL = "insert into todos(title, username, description, target_date,is_done) "
				+ "value (?,?,?,?,?)";

		try {
			Connection conn = JDBCUtils.getConnection();
			PreparedStatement pstmt = conn.prepareStatement(INSERT_USER_SQL);
			pstmt.setString(1, todo.getTitle());
			pstmt.setString(2, todo.getUsername());
			pstmt.setString(3, todo.getDescription());
			pstmt.setDate(4, JDBCUtils.getSQLDate(todo.getTargetDate())); // ToDo에 입력된 날짜를 SQL문에 입력될 날짜타입으로 변경
			pstmt.setBoolean(5, todo.isStatus()); // pstmt 완성

			pstmt.executeUpdate(); // pstmt 실행, 결과가 없는 Update, Delete, Drop, Insert 등은 executeUpdate() 사용
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}

	@Override
	public Todo selectTodo(long todoId) {
		String SELECT_TODO_BY_ID = "SELECT id, title, username, description, target_date, is_done from todos where id = ?";
		Todo todo = null;
		try {
			Connection conn = JDBCUtils.getConnection();
			PreparedStatement pstmt = conn.prepareStatement(SELECT_TODO_BY_ID);
			
			pstmt.setLong(1, todoId);
			
			ResultSet rs = pstmt.executeQuery();
			
			if (rs.next()) {// 결과가 있을 경우에 값을 저장한다.
				long id = rs.getLong("id");
				String title = rs.getString("title");
				String username = rs.getString("username");
				String description = rs.getString("description");
				LocalDate targetDate = rs.getDate("target_date").toLocalDate();
				Boolean status = rs.getBoolean("is_done");
				todo = new Todo(id, title, username, description, targetDate, status);
			}
		} catch (SQLException e) {
			System.out.println("SQL ToDo 검색 ERROR!");
		}
		return todo;
	}

	@Override
	public List<Todo> selectAllTodos() {
		String SELECT_TODO_BY_ID = "SELECT * from todos";
		List<Todo> todos = new ArrayList<Todo>(); // 빈 ArrayList 생성
		try {
			Connection conn = JDBCUtils.getConnection();
			PreparedStatement pstmt = conn.prepareStatement(SELECT_TODO_BY_ID);
			
			ResultSet rs = pstmt.executeQuery();
			
			// 결과가 여러줄 일 때 while문을 사용하여 처리
			while (rs.next()) {// 결과가 있을 경우에 값을 저장한다.
				long id = rs.getLong("id");
				String title = rs.getString("title");
				String username = rs.getString("username");
				String description = rs.getString("description");
				LocalDate targetDate = rs.getDate("target_date").toLocalDate();
				Boolean status = rs.getBoolean("is_done");
				todos.add(new Todo(id, title, username, description, targetDate, status));
			}
			
		} catch (SQLException e) {
			System.out.println("SQL ToDo 검색 ERROR!");
			return null;
		}
		System.out.println("SERCH 완료");
		return todos;
	}

	@Override
	public boolean deleteTodo(long todoId) {
		String DELETE_SQL = "delete from todos where id = ?";
		boolean status = false;	
		try {
			Connection conn = JDBCUtils.getConnection();
			PreparedStatement pstmt = conn.prepareStatement(DELETE_SQL);
			pstmt.setLong(1, todoId);

			status = pstmt.executeUpdate() > 0; // 한 줄 이상 삭제가 되면 true
			
		} catch (SQLException e) {
			System.out.println("SQL DELETE TOD ERROR");
			return false;
		}
		System.out.println("DELETE 완료");
		return status;
	}

	@Override
	public boolean updateTodo(Todo todo) {
		String UPDATE_SQL = "update todos set description = ?, title = ?, username = ?, target_date = ?, is_done = ? where id = ? ";
		boolean status = false;	
		try {
			Connection conn = JDBCUtils.getConnection();
			PreparedStatement pstmt = conn.prepareStatement(UPDATE_SQL);
			pstmt.setString(1, todo.getDescription());
			pstmt.setString(2, todo.getTitle());
			pstmt.setString(3, todo.getUsername());
			pstmt.setDate(4, JDBCUtils.getSQLDate(todo.getTargetDate()));		
			pstmt.setBoolean(5, todo.isStatus());
			pstmt.setLong(6, todo.getId());

			status = pstmt.executeUpdate() > 0; // 한 줄 이상 Update가 되면 true			
			
		} catch (SQLException e) {
			System.out.println("SQL UPDATE TODO ERROR");
			return false;
		}
		System.out.println("UPDATE 완료");
		return status;
	}

}

Todo Controller 생성하기 (미완)

package todoApp.controller;

import java.io.IOException;
import java.util.List;

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

import todoApp.dao.TodoDao;
import todoApp.dao.TodoDaoImpl;
import todoApp.model.Todo;


// SERVLET 주소가 "/"이면 다른 서블릿 주소(/register, /login)를 제외한 모든 요청이 여기에서 처리함 (web.xml에서 welcomefile 지워야함!)
// 그렇지 않으면 switch문의 default 떄문에 무한오류 생김
@WebServlet("/")
public class TodoController extends HttpServlet {
	private static final long serialVersionUID = 1L;
	
	private TodoDao todoDAO;
	
	public void init() {
		todoDAO = new TodoDaoImpl(); // 실제 객체는 todoDao를 구현한 ToDoDaoImpl로 생성
	}

	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// 요청주소가 localhost:8090/TODO/new = > "/new"가 action의 값
		String action = request.getServletPath();
		
		switch(action) {
		case "/new" : showNewForm(request, response); break;
		case "/insert" : insertTodo(request, response); break;
		case "/delete" : deleteTodo(request, response); break;
		case "/edit" : showEditForm(request, response); break;
		case "/update" : updateTodo(request, response); break;
		case "/list" : listTodo(request, response); break; // localhost8090:TODO/list
		default : // 요청 주소가 기본 또는 잘못되었을 경우 login페이지로 이동 
			RequestDispatcher dispatcher = request.getRequestDispatcher("login/login.jsp");
			dispatcher.forward(request, response); break;
		} 
	}

	private void showNewForm(HttpServletRequest request, HttpServletResponse response) {
		// TODO Auto-generated method stub
		
	}

	private void insertTodo(HttpServletRequest request, HttpServletResponse response) {
		// TODO Auto-generated method stub
		
	}

	private void deleteTodo(HttpServletRequest request, HttpServletResponse response) {
		// TODO Auto-generated method stub
		
	}

	private void showEditForm(HttpServletRequest request, HttpServletResponse response) {
		// TODO Auto-generated method stub
		
	}

	private void updateTodo(HttpServletRequest request, HttpServletResponse response) {
		// TODO Auto-generated method stub
		
	}

	private void listTodo(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		List<Todo> listTodo = todoDAO.selectAllTodos(); // DB에서 할일들을 가져와 list에 저장
		request.setAttribute("listTodo", listTodo);		// list를 request에 저장
		
		RequestDispatcher dispatcher = request.getRequestDispatcher("todo/todo-list.jsp");
		dispatcher.forward(request, response);
	}

	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		doGet(request, response);
	}

}

Todo list 페이지 생성

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html lang="ko">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <link
      rel="stylesheet"
      href="<%=request.getContextPath()%>/css/bootstrap.min.css"
    />
    <link rel="stylesheet" href="<%=request.getContextPath()%>/css/style.css" />
    <title>Todo리스트</title>
  </head>
  <body>
    <header>
      <nav class="navbar navbar-expand-lg navbar-dark bg-dark">
        <div class="container-fluid">
          <a class="navbar-brand" href="#">TODO APP</a>
          <button
            class="navbar-toggler"
            type="button"
            data-bs-toggle="collapse"
            data-bs-target="#navbarSupportedContent"
            aria-controls="navbarSupportedContent"
            aria-expanded="false"
            aria-label="Toggle navigation"
          >
            <span class="navbar-toggler-icon"></span>
          </button>
          <div class="collapse navbar-collapse" id="navbarSupportedContent">
            <ul class="navbar-nav ms-auto mb-2 mb-lg-0">
              <li class="nav-item">
                <a class="nav-link" href="<%=request.getContextPath()%>/list"
                  >ToDo 리스트</a
                >
              </li>
            </ul>
            <ul class="navbar-nav mb-2">
              <li class="nav-item">
                <a class="nav-link" href="<%=request.getContextPath()%>/logout"
                  >로그아웃</a
                >
              </li>
            </ul>
          </div>
        </div>
      </nav>
    </header>
    <!-- navbar 끝 -->
    <!-- 본문 -->
    <div class="container">
      <h3 class="text-center">DO IT list's</h3>
      <hr />
      <div class="container text-left">
        <a href="" class="btn btn-success">할일 추가</a> <!-- 여기 미완성-->
      </div>
      <br />
      <table class="table table-bordered">
        <thead>
          <tr>
            <th>제목</th>
            <th>마감 일자</th>
            <th>현재 상태</th>
            <th>액션</th>
          </tr>
        </thead>
        <tbody></tbody>
      </table>
    </div>
    <!-- 본문 끝 -->
    <jsp:include page="../common/footer.jsp" />
    <script src="<%=request.getContextPath()%>/js/bootstrap.bundle.min.js"></script>
  </body>
</html>