6段階目（DAOのデータ更新メソッドを作成→更新処理完成）

.classpath

@@ -1,8 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<classpath>
-	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
-	<classpathentry kind="src" path="src"/>
-	<classpathentry kind="lib" path="lib/mysql-connector-java-8.0.23.jar"/>
-	<classpathentry kind="lib" path="実行例/DAO_Simple.jar"/>
-	<classpathentry kind="output" path="bin"/>
-</classpath>

.gitignore

@@ -1 +0,0 @@
-/bin/

.project

@@ -1,23 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<projectDescription>
-	<name>em-jdbc</name>
-	<comment></comment>
-	<projects>
-	</projects>
-	<buildSpec>
-		<buildCommand>
-			<name>org.eclipse.wst.validation.validationbuilder</name>
-			<arguments>
-			</arguments>
-		</buildCommand>
-		<buildCommand>
-			<name>org.eclipse.jdt.core.javabuilder</name>
-			<arguments>
-			</arguments>
-		</buildCommand>
-	</buildSpec>
-	<natures>
-		<nature>org.eclipse.jdt.core.javanature</nature>
-		<nature>org.eclipse.wst.jsdt.core.jsNature</nature>
-	</natures>
-</projectDescription>

.settings/.jsdtscope

@@ -1,7 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<classpath>
-	<classpathentry kind="con" path="org.eclipse.wst.jsdt.launching.JRE_CONTAINER"/>
-	<classpathentry kind="con" path="org.eclipse.wst.jsdt.launching.baseBrowserLibrary"/>
-	<classpathentry kind="src" path=""/>
-	<classpathentry kind="output" path=""/>
-</classpath>

.settings/org.eclipse.wst.jsdt.ui.superType.container

@@ -1 +0,0 @@
-org.eclipse.wst.jsdt.launching.JRE_CONTAINER

.settings/org.eclipse.wst.jsdt.ui.superType.name

@@ -1 +0,0 @@
-Global

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

@@ -61,14 +61,9 @@ public class EmployeeDAO {
 			this.stmt = con.prepareStatement(sql.toString());
 			rs = stmt.executeQuery();
 			while (rs.next()) {
-				//インスタンス生成
+				EmployeeDTO dto = new EmployeeDTO(rs.getInt(ID_EMPLOYEE), rs.getString(NM_EMPLOYEE),
-				EmployeeDTO dto = new EmployeeDTO();
+						rs.getString(KN_EMPLOYEE), rs.getString(MAIL_ADDRESS), rs.getString(PASSWORD),
-				dto.setId_employee(rs.getInt("id_employee"));
+						rs.getInt(ID_DEPARTMENT));
-				dto.setNm_employee(rs.getString("nm_employee"));
-				dto.setKn_employee(rs.getString("kn_employee"));
-				dto.setMail_address(rs.getString("mail_address"));
-				dto.setPassword(rs.getString("password"));
-				dto.setId_department(rs.getInt("id_department"));
 				rtnList.add(dto);
 			}
 		} finally {
@@ -77,4 +72,159 @@ public class EmployeeDAO {
 		return rtnList;
 	}
 
+	/**
+	 * 社員テーブルから社員IDに合致する情報を取得する
+	 * @param id
+	 * 			検索する社員ID
+	 * @return 検索結果
+	 * @throws SQLException
+	 * @throws ClassNotFoundException
+	 * @throws NumberFormatException
+	 */
+	public List<EmployeeDTO> selectById​(int id)
+			throws SQLException, ClassNotFoundException, NumberFormatException {
+		List<EmployeeDTO> rtnList = new ArrayList<>();
+		StringBuilder sql = new StringBuilder();
+		sql.append(" SELECT ");
+		sql.append("    " + "*");
+		sql.append(" FROM ");
+		sql.append("    " + TBL_NAME);
+		sql.append(" WHERE ");
+		sql.append("    " + ID_EMPLOYEE);
+		sql.append(" = ");
+		sql.append("    " + id);
+		try {
+
+			this.stmt = con.prepareStatement(sql.toString());
+			rs = stmt.executeQuery();
+			while (rs.next()) {
+
+				EmployeeDTO dto = new EmployeeDTO(rs.getInt(ID_EMPLOYEE), rs.getString(NM_EMPLOYEE),
+						rs.getString(KN_EMPLOYEE), rs.getString(MAIL_ADDRESS), rs.getString(PASSWORD),
+						rs.getInt(ID_DEPARTMENT));
+				rtnList.add(dto);
+
+			}
+		} finally {
+			DbUtil.closeStatement(this.stmt);
+		}
+		if (rtnList.size() == 0) {
+			System.out.println("入力された値で情報がみつかりませんでした");
+		}
+		return rtnList;
+	}
+
+	/**
+	 * 社員テーブルの社員IDに合致する情報を削除する
+	 *
+	 * @param id
+	 *			削除ID
+	 * @throws ClassNotFoundException
+	 * @throws SQLException
+	 * @throws NumberFormatException
+	 */
+	public void empDelete​(int id)
+			throws ClassNotFoundException, SQLException, NumberFormatException {
+		StringBuilder sql = new StringBuilder();
+		sql.append(" DELETE ");
+		sql.append(" FROM ");
+		sql.append("    " + TBL_NAME);
+		sql.append(" WHERE ");
+		sql.append("    " + ID_EMPLOYEE);
+		sql.append(" = ");
+		sql.append("    " + id);
+
+		try {
+			this.stmt = con.prepareStatement(sql.toString());
+			stmt.executeUpdate();
+			System.out.println("削除が完了しました");
+		} finally {
+			DbUtil.closeStatement(this.stmt);
+		}
+
+	}
+
+	/**
+	 * 社員テーブルに指定された情報を新規登録する
+	 *
+	 * @param name - 社員名
+	 * @param kana - 社員名カナ
+	 * @param mail - メールアドレス
+	 * @param pass - パスワード
+	 * @param depId - 部署ID
+	 * @throws NumberFormatException
+	 * @throws SQLException
+	 * @throws ClassNotFoundException
+	 */
+	public void empInsert​(String name, String kana, String mail, String pass, int depId)
+			throws NumberFormatException, SQLException, ClassNotFoundException {
+		StringBuilder sql = new StringBuilder();
+		sql.append(" INSERT ");
+		sql.append(" INTO ");
+		sql.append("    " + TBL_NAME);
+		sql.append(" ( " + NM_EMPLOYEE);
+		sql.append(" , " + KN_EMPLOYEE);
+		sql.append(" , " + MAIL_ADDRESS);
+		sql.append(" , " + PASSWORD);
+		sql.append(" , " + ID_DEPARTMENT + " ) ");
+		sql.append(" VALUES ");
+		sql.append(" ( '" + name);
+		sql.append("' , '" + kana);
+		sql.append("' , '" + mail);
+		sql.append("' , '" + pass);
+		sql.append("' , " + depId + " ) ");
+
+		try {
+			this.stmt = con.prepareStatement(sql.toString());
+			stmt.executeUpdate();
+			System.out.println("登録が完了しました");
+		} finally {
+			DbUtil.closeStatement(this.stmt);
+		}
+	}
+
+	/**
+	 * 社員テーブルの社員IDに合致する情報を更新する
+	 *
+	 * @param id - 社員ID
+	 * @param name - 社員名
+	 * @param kana - 社員名カナ
+	 * @param mail - メールアドレス
+	 * @param pass - パスワード
+	 * @param depId - 部署ID
+	 * @throws ClassNotFoundException
+	 * @throws SQLException
+	 * @throws NumberFormatException
+	
+	 */
+	public void empUpdate​(int id, String name, String kana, String mail, String pass, int depId)
+			throws ClassNotFoundException, SQLException, NumberFormatException {
+		StringBuilder sql = new StringBuilder();
+		sql.append(" UPDATE ");
+		sql.append("    " + TBL_NAME);
+		sql.append(" SET ");
+		sql.append("    " + NM_EMPLOYEE);
+		sql.append(" = '" + name + " ' ");
+		sql.append(" , " + KN_EMPLOYEE);
+		sql.append(" = '" + kana + " ' ");
+		sql.append(" , " + MAIL_ADDRESS);
+		sql.append(" = '" + mail + " ' ");
+		sql.append(" , " + PASSWORD);
+		sql.append(" = '" + pass + " ' ");
+		sql.append(" , " + ID_DEPARTMENT);
+		sql.append(" = " + depId);
+		sql.append(" WHERE ");
+		sql.append("    " + ID_EMPLOYEE);
+		sql.append(" = ");
+		sql.append("    " + id);
+
+		try {
+			this.stmt = con.prepareStatement(sql.toString());
+			stmt.executeUpdate();
+			System.out.println("更新が完了しました");
+		} finally {
+			DbUtil.closeStatement(this.stmt);
+		}
+
+	}
 }

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

@@ -1,61 +1,79 @@
 package com.rhizome.example.dto;
 
 public class EmployeeDTO {
-	//フィールド宣言
+	private int ID_EMPLOYEE;
-	private Integer id_employee;//社員ID
+	private String NM_EMPLOYEE;
-	private String nm_employee;//社員名
+	private String KN_EMPLOYEE;
-	private String kn_employee;//社員名カナ
+	private String MAIL_ADDRESS;
-	private String mail_address;//メールアドレス
+	private String PASSWORD;
-	private String password;//パスワード
+	private int ID_DEPARTMENT;
-	private Integer id_department;//部署ID
+
+	public EmployeeDTO() {
 
-	//getter/setter
-	public Integer getId_employee() {
-		return id_employee;
 	}
 
-	public void setId_employee(Integer id_employee) {
+	public EmployeeDTO(int ID_EMPLOYEE, String NM_EMPLOYEE, String KN_EMPLOYEE, String MAIL_ADDRESS, String PASSWORD,
-		this.id_employee = id_employee;
+			int ID_DEPARTMENT) {
+		setID_EMPLOYEE(ID_EMPLOYEE);
+		setNM_EMPLOYEE(NM_EMPLOYEE);
+		setKN_EMPLOYEE(KN_EMPLOYEE);
+		setMAIL_ADDRESS(MAIL_ADDRESS);
+		setPASSWORD(PASSWORD);
+		setID_DEPARTMENT(ID_DEPARTMENT);
 	}
 
-	public String getNm_employee() {
+	public int getID_EMPLOYEE() {
-		return nm_employee;
+		return ID_EMPLOYEE;
 	}
 
-	public void setNm_employee(String nm_employee) {
+	public void setID_EMPLOYEE(int iD_EMPLOYEE) {
-		this.nm_employee = nm_employee;
+		ID_EMPLOYEE = iD_EMPLOYEE;
 	}
 
-	public String getKn_employee() {
+	public String getNM_EMPLOYEE() {
-		return kn_employee;
+		return NM_EMPLOYEE;
 	}
 
-	public void setKn_employee(String kn_employee) {
+	public void setNM_EMPLOYEE(String nM_EMPLOYEE) {
-		this.kn_employee = kn_employee;
+		NM_EMPLOYEE = nM_EMPLOYEE;
 	}
 
-	public String getMail_address() {
+	public String getKN_EMPLOYEE() {
-		return mail_address;
+		return KN_EMPLOYEE;
 	}
 
-	public void setMail_address(String mail_address) {
+	public void setKN_EMPLOYEE(String kN_EMPLOYEE) {
-		this.mail_address = mail_address;
+		KN_EMPLOYEE = kN_EMPLOYEE;
 	}
 
-	public String getPassword() {
+	public String getMAIL_ADDRESS() {
-		return password;
+		return MAIL_ADDRESS;
 	}
 
-	public void setPassword(String password) {
+	public void setMAIL_ADDRESS(String mAIL_ADDRESS) {
-		this.password = password;
+		MAIL_ADDRESS = mAIL_ADDRESS;
 	}
 
-	public Integer getId_department() {
+	public String getPASSWORD() {
-		return id_department;
+		return PASSWORD;
 	}
 
-	public void setId_department(Integer id_department) {
+	public void setPASSWORD(String pASSWORD) {
-		this.id_department = id_department;
+		PASSWORD = pASSWORD;
+	}
+
+	public int getID_DEPARTMENT() {
+		return ID_DEPARTMENT;
+	}
+
+	public void setID_DEPARTMENT(int iD_DEPARTMENT) {
+		ID_DEPARTMENT = iD_DEPARTMENT;
+	}
+
+	public void showInfo() {
+		System.out.println(ID_EMPLOYEE + "\t" + NM_EMPLOYEE +
+				"\t" + KN_EMPLOYEE + "\t" + MAIL_ADDRESS +
+				"\t" + PASSWORD + "\t" + ID_DEPARTMENT);
 	}
 
 }

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

@@ -54,10 +54,13 @@ public class Main {
 			empSelect();
 			break;
 		case "2":
+			empInsert​();
 			break;
 		case "3":
+			empUpdate​();
 			break;
 		case "4":
+			empDelete​();
 			break;
 		case "9":
 			return;
@@ -70,6 +73,93 @@ public class Main {
 		}
 	}
 
+	/**
+	 * 社員テーブルの社員IDに合致する情報を更新する
+	 *
+	 * @throws ClassNotFoundException
+	 * @throws SQLException
+	 * @throws NumberFormatException
+	 */
+	public static void empUpdate​()
+			throws ClassNotFoundException, SQLException, NumberFormatException {
+		Connection con = DbUtil.getConnection();
+		EmployeeDAO empDao = new EmployeeDAO(con);
+		int id = Integer.parseInt(inputCheck("ID", true));
+
+		if (empDao.selectById​(id).size() == 0) {
+			return;
+		}
+		String name = inputCheck("社員名", false);
+		String kana = inputCheck("フリガナ", false);
+		String mail = inputCheck("メールアドレス", false);
+		String pass = inputCheck("パスワード", false);
+		int depId = Integer.parseInt(inputCheck("部署ID", true));
+
+		try {
+			empDao.empUpdate​(id, name, kana, mail, pass, depId);
+		} finally {
+			DbUtil.closeConnection(empDao.con);
+		}
+	}
+
+	/**
+	 * 社員テーブルに指定された情報を新規登録する
+	 * @throws NumberFormatException
+	 * @throws SQLException
+	 * @throws ClassNotFoundException
+	 */
+	public static void empInsert​()
+			throws NumberFormatException, SQLException, ClassNotFoundException {
+		Connection con = DbUtil.getConnection();
+		EmployeeDAO empDao = new EmployeeDAO(con);
+
+		String name = inputCheck("社員名", false);
+		String kana = inputCheck("フリガナ", false);
+		String mail = inputCheck("メールアドレス", false);
+		String pass = inputCheck("パスワード", false);
+		int depId = Integer.parseInt(inputCheck("部署ID", true));
+
+		try {
+			empDao.empInsert​(name, kana, mail, pass, depId);
+		} finally {
+			DbUtil.closeConnection(empDao.con);
+		}
+
+	}
+
+	/**
+	 * 社員テーブルの社員IDに合致する情報を削除する
+	 *
+	 * @throws ClassNotFoundException
+	 * @throws SQLException
+	 */
+	public static void empDelete​()
+			throws ClassNotFoundException, SQLException, NumberFormatException {
+		List<EmployeeDTO> rtnList = new ArrayList<>();
+		Connection con = DbUtil.getConnection();
+		EmployeeDAO empDao = new EmployeeDAO(con);
+		int id = Integer.parseInt(inputCheck("ID", true));
+		rtnList = empDao.selectById​(id);
+		if (rtnList.size() == 0) {
+			return;
+		}
+
+		System.out.println("指定されたIDの情報を削除します？ Y/y\r\n"
+				+ "（Y/y以外の入力であればキャンセル）");
+
+		String str = inputCheck(false);
+
+		if (!str.equalsIgnoreCase("y")) {
+			System.out.println("キャンセルしました");
+			return;
+		}
+		try {
+			empDao.empDelete​(id);
+		} finally {
+			DbUtil.closeConnection(empDao.con);
+		}
+	}
+
 	/**
 	 * 社員テーブルから情報を検索する
 	 *
@@ -87,11 +177,14 @@ public class Main {
 			case "1":
 				empList = empDao.selectAll();
 				break;
+			case "2":
+				empList = empDao.selectById​(Integer.parseInt(inputCheck("ID", true)));
+				break;
 			default:
 				return;
 			}
 			for (EmployeeDTO emp : empList) {
-				System.out.println(emp);
+				emp.showInfo();
 			}
 		} finally {
 			DbUtil.closeConnection(empDao.con);
@@ -147,4 +240,26 @@ public class Main {
 		}
 		return str;
 	}
+
+	public static String inputCheck(boolean flg) {
+		String str = null;
+		while (true) {
+			str = sc.nextLine();
+			if (str.trim().length() == 0) {
+
+				continue;
+			}
+			if (flg) {
+				if (str.trim().length() > 0) {
+					try {
+						Integer.parseInt(str);
+					} catch (NumberFormatException e) {
+						continue;
+					}
+				}
+			}
+			break;
+		}
+		return str;
+	}
 }

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

@@ -4,6 +4,7 @@ import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.PreparedStatement;
 import java.sql.SQLException;
+import java.util.Objects;
 
 public class DbUtil {
 	// 定数定義（共通）
@@ -44,10 +45,13 @@ 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 SQLException {
+
-		//データベースへの接続
+	public static Connection getConnection() throws ClassNotFoundException, SQLException {
-		con = DriverManager.getConnection(DB_URL, DB_USER, DB_PASS);
+		if (con != null && con.isValid(1)) {
-		return con;
+			return con;
+		}
+		Class.forName(DB_DRIVER);
+		return con = DriverManager.getConnection(DB_URL, DB_USER, DB_PASS);
 	}
 
 	/*
@@ -59,11 +63,10 @@ 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 {
+
-		//nullチェック
+	public static void closeStatement(PreparedStatement ps) throws SQLException {
-		if (stmt != null) {
+		if (Objects.nonNull(ps))
-			stmt.close();
+			ps.close();
-		}
 	}
 
 	/*
@@ -76,10 +79,8 @@ public class DbUtil {
 	 * 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 {
-		//nullチェック
+		if (Objects.nonNull(con))
-		if (con != null) {
 			con.close();
-
-		}
 	}
+
 }