1段階目です。

src/com/rhizome/example/dao/EmployeeDAO.java

@@ -13,7 +13,6 @@ import java.sql.SQLException;
 import java.util.ArrayList;
 import java.util.List;
 
-import com.rhizome.example.dto.EmployeeDTO;
 import com.rhizome.example.util.DbUtil;
 
 public class EmployeeDAO {
@@ -49,8 +48,8 @@ public class EmployeeDAO {
 	 * @throws SQLException
 	 * @throws ClassNotFoundException
 	 */
-	public List<EmployeeDTO> selectAll() throws SQLException, ClassNotFoundException {
-		List<EmployeeDTO> rtnList = new ArrayList<>();
+	public List<String> selectAll() throws SQLException, ClassNotFoundException {
+		List<String> rtnList = new ArrayList<>();
 		StringBuilder sql = new StringBuilder();
 		sql.append(" SELECT ");
 		sql.append("    " + "*");
@@ -61,15 +60,7 @@ public class EmployeeDAO {
 			this.stmt = con.prepareStatement(sql.toString());
 			rs = stmt.executeQuery();
 			while (rs.next()) {
-				EmployeeDTO dto = new EmployeeDTO();
-				dto.setIdEmployee(rs.getInt(ID_EMPLOYEE));
-				dto.setNmEmployee(rs.getString(NM_EMPLOYEE));
-				dto.setKnEmployee(rs.getString(KN_EMPLOYEE));
-				dto.setMailAddress(rs.getString(MAIL_ADDRESS));
-				dto.setPassword(rs.getString(PASSWORD));
-				dto.setIdDepartment(rs.getInt(ID_DEPARTMENT));
-
-				rtnList.add(dto);
+				rtnList.add(rs.getString(NM_EMPLOYEE));
 			}
 		} finally {
 			DbUtil.closeStatement(this.stmt);
@@ -77,50 +68,4 @@ public class EmployeeDAO {
 		return rtnList;
 	}
 
-	public List<EmployeeDTO> selectById(int id) throws SQLException, ClassNotFoundException {
-		List<EmployeeDTO> rtnList = new ArrayList<>();
-		StringBuilder sql = new StringBuilder();
-		sql.append(" SELECT ");
-		sql.append(" * ");
-		sql.append(" FROM ");
-		sql.append(TBL_NAME);
-		sql.append(" WHERE ID_EMPLOYEE = ? ");
-		try {
-
-			this.stmt = con.prepareStatement(sql.toString());
-			this.stmt.setInt(1, id);
-			rs = this.stmt.executeQuery();
-			while (rs.next()) {
-				EmployeeDTO dto = new EmployeeDTO();
-				dto.setIdEmployee(rs.getInt(ID_EMPLOYEE));
-				dto.setNmEmployee(rs.getString(NM_EMPLOYEE));
-				dto.setKnEmployee(rs.getString(KN_EMPLOYEE));
-				dto.setMailAddress(rs.getString(MAIL_ADDRESS));
-				dto.setPassword(rs.getString(PASSWORD));
-				dto.setIdDepartment(rs.getInt(ID_DEPARTMENT));
-
-				rtnList.add(dto);
-			}
-		} finally {
-			DbUtil.closeStatement(this.stmt);
-		}
-		return rtnList;
-	}
-
-	//社員データ削除
-	public void empDelete(int id) throws SQLException {
-		StringBuilder sql = new StringBuilder();
-		sql.append(" DELETE ");
-		sql.append(" FROM ");
-		sql.append(TBL_NAME);
-		sql.append(" WHERE ID_EMPLOYEE = ? ");
-		try {
-			this.stmt = con.prepareStatement(sql.toString());
-			this.stmt.setInt(1, id);
-			this.stmt.executeUpdate();
-		} finally {
-			DbUtil.closeStatement(this.stmt);
-
-		}
-	}
 }

src/com/rhizome/example/dto/EmployeeDTO.java

@@ -1,59 +0,0 @@
-package com.rhizome.example.dto;
-
-public class EmployeeDTO {
-	private int idEmployee;
-	private String nmEmployee;
-	private String knEmployee;
-	private String mailAddress;
-	private String password;
-	private int idDepartment;
-
-	public int getIdEmployee() {
-		return idEmployee;
-	}
-
-	public void setIdEmployee(int idEmployee) {
-		this.idEmployee = idEmployee;
-	}
-
-	public String getNmEmployee() {
-		return nmEmployee;
-	}
-
-	public void setNmEmployee(String nmEmployee) {
-		this.nmEmployee = nmEmployee;
-	}
-
-	public String getKnEmployee() {
-		return knEmployee;
-	}
-
-	public void setKnEmployee(String knEmployee) {
-		this.knEmployee = knEmployee;
-	}
-
-	public String getMailAddress() {
-		return mailAddress;
-	}
-
-	public void setMailAddress(String mailAddress) {
-		this.mailAddress = mailAddress;
-	}
-
-	public String getPassword() {
-		return password;
-	}
-
-	public void setPassword(String password) {
-		this.password = password;
-	}
-
-	public int getIdDepartment() {
-		return idDepartment;
-	}
-
-	public void setIdDepartment(int idDepartment) {
-		this.idDepartment = idDepartment;
-	}
-
-}

src/com/rhizome/example/main/Main.java

@@ -7,7 +7,6 @@ import java.util.List;
 import java.util.Scanner;
 
 import com.rhizome.example.dao.EmployeeDAO;
-import com.rhizome.example.dto.EmployeeDTO;
 import com.rhizome.example.util.DbUtil;
 
 /**
@@ -58,7 +57,6 @@ public class Main {
 		case "3":
 			break;
 		case "4":
-			empDelete();
 			break;
 		case "9":
 			return;
@@ -78,7 +76,7 @@ public class Main {
 	 * @throws SQLException
 	 */
 	public static void empSelect() throws ClassNotFoundException, SQLException {
-		List<EmployeeDTO> empList = new ArrayList<>();
+		List<String> empList = new ArrayList<>();
 		Connection con = DbUtil.getConnection();
 		EmployeeDAO empDao = new EmployeeDAO(con);
 		System.out.println("1:全検索 2:条件検索 それ以外:戻る");
@@ -88,60 +86,17 @@ public class Main {
 			case "1":
 				empList = empDao.selectAll();
 				break;
-			case "2":
-				String id = inputCheck("ID", true);
-				empList = empDao.selectById(Integer.parseInt(id));
-				break;
 			default:
 				return;
 			}
-			if (empList.isEmpty()) {
-				System.out.println("入力された値で情報がみつかりませんでした");
-			} else {
-				for (EmployeeDTO emp : empList) {
-					System.out.println(
-							emp.getIdEmployee() + " "
-									+ emp.getNmEmployee() + " "
-									+ emp.getKnEmployee() + " "
-									+ emp.getMailAddress() + " "
-									+ emp.getPassword() + " "
-									+ emp.getIdDepartment());
-				}
+			for (String emp : empList) {
+				System.out.println(emp);
 			}
-
 		} finally {
 			DbUtil.closeConnection(empDao.con);
 		}
 	}
 
-	//社員テーブルから情報を削除する
-	public static void empDelete()
-			throws ClassNotFoundException, SQLException {
-		Connection con = DbUtil.getConnection();
-		EmployeeDAO empDao = new EmployeeDAO(con);
-		String id = inputCheck("ID", true);
-
-		try {
-			List<EmployeeDTO> empList = empDao.selectById(Integer.parseInt(id));
-
-			if (empList.isEmpty()) {
-				System.out.println("入力されて値で情報がみつかりませんでした");
-			} else {
-				System.out.println("指定されたIDの情報を削除しますか? Y/y");
-				System.out.println("Y/y以外の入力であればキャンセル");
-
-				String confirm = sc.nextLine();
-
-				if (confirm.equalsIgnoreCase("y")) {
-					empDao.empDelete(Integer.parseInt(id));
-					System.out.println("削除が完了しました");
-				}
-			}
-		} finally {
-			DbUtil.closeConnection(con);
-		}
-	}
-
 	/**
 	 * フラグを判定し、テーブル名を取得する
 	 *

src/com/rhizome/example/util/DbUtil.java

@@ -44,12 +44,18 @@ public class DbUtil {
 	 * 				  生成されたConnectionを返却する
 	 * 				  ※Connection生成には上記の定数を活用してください
 	 */
-	public static Connection getConnection()
-			throws ClassNotFoundException, SQLException {
-		Class.forName(DB_DRIVER);
-		con = DriverManager.getConnection(DB_URL, DB_USER, DB_PASS);
+	public static Connection getConnection() throws ClassNotFoundException, SQLException {
+		try {
+			Class.forName(DB_DRIVER);
+			return DriverManager.getConnection(DB_URL, DB_USER, DB_PASS);
+		} catch (ClassNotFoundException e) {
+			System.out.println();
+			throw e;
+		} catch (SQLException e) {
+			System.out.println();
+			throw e;
+		}
 
-		return con;
 	}
 
 	/*
@@ -61,10 +67,13 @@ public class DbUtil {
 	 * 例外			：SQLException
 	 * 処理			：引数のDBステートメントがnullでない場合、そのDBステートメントをクローズする
 	 */
-	public static void closeStatement(PreparedStatement stmt)
-			throws SQLException {
+	public static void closeStatement(PreparedStatement stmt) {
 		if (stmt != null) {
-			stmt.close();
+			try {
+				stmt.close();
+			} catch (SQLException e) {
+				System.out.println();
+			}
 		}
 	}
 
@@ -77,10 +86,15 @@ public class DbUtil {
 	 * 例外			：SQLException
 	 * 処理			：引数のコネクションがnullでない場合、そのコネクションを切断する
 	 */
-	public static void closeConnection(Connection con)
-			throws SQLException {
+	public static void closeConnection(Connection con) {
 		if (con != null) {
-			con.close();
+			try {
+				if (!con.isClosed()) {
+					con.close();
+				}
+			} catch (SQLException e) {
+				e.printStackTrace();
+			}
 		}
 	}