1、建立Java Project專案

2、匯入Jar包

3、建立資料庫
//根據實體類建立資料庫

4、建立實體類 (Bm.java)
public class Bm {
private int id;
private String rq;
private String nr;
private String zz;
private String tq;
private String bt;
public int getId() {
return id;
}

public void setId(int id) {
this.id = id;
}
public String getRq() {
return rq;
}
public void setRq(String rq) {
this.rq = rq;
}
public String getNr() {
return nr;
}
public void setNr(String nr) {
this.nr = nr;
}
public String getZz() {
return zz;
}
public void setZz(String zz) {
this.zz = zz;
}
public String getTq() {
return tq;
}
public void setTq(String tq) {
this.tq = tq;
}
public String getBt() {
return bt;
}
public void setBt(String bt) {
this.bt = bt;
}
//@Override
//public String toString() {
// return “Bm [id=” + id + “, rq=” + rq + “, nr=” + nr + “, zz=” + zz
// + “, tq=” + tq + “, bt=” + bt + “]”;
//}
}

5、建立資料庫驅動類 (DBUtil.java)
public class DBUtil {
//連結資料庫 相當於橋樑
public static Connection getConnection(){
Connection conn=null;
try {
Class.forName(“com.mysql.jdbc.Driver”);
conn=DriverManager.getConnection(“jdbc:mysql://localhost:3306/test?useSSL=false”,”root”,”root”);
} catch (Exception e) {
e.printStackTrace();
}
return conn;
}
}
6.建立資料庫操作類（BankDao.java）
public class BankDao {
// 查詢所有
public ArrayList getList() {
ArrayList ar = new ArrayList();
Connection conn = DBUtil.getConnection();
PreparedStatement ps = null;
ResultSet rs = null;
try {
String sql = “select * from journal”;
ps = conn.prepareStatement(sql);
rs = ps.executeQuery();
while (rs.next()) {
Bm bankm = new Bm();
bankm.setId(rs.getInt(“id”));
bankm.setRq(rs.getString(“rq”));
bankm.setNr(rs.getString(“nr”));
bankm.setZz(rs.getString(“zz”));
bankm.setTq(rs.getString(“tq”));
bankm.setBt(rs.getString(“bt”));
ar.add(bankm);
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
try {
if (rs != null) {
rs.close();
}
if (ps != null) {
ps.close();
}
if (conn != null) {
conn.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
return ar;
}

// 新增使用者
public void inset(Bm Bankm) {
    Connection conn = DBUtil.getConnection();
    PreparedStatement ps = null;
    String sql = "insert into journal(rq,nr,zz,tq,bt)values(?,?,?,?,?)";
    try {
        ps = conn.prepareStatement(sql);
        ps.setString(1, Bankm.getRq());
        ps.setString(2, Bankm.getNr());
        ps.setString(3, Bankm.getZz());
        ps.setString(4, Bankm.getTq());
        ps.setString(5, Bankm.getBt());
        int a = ps.executeUpdate();
        if (a > 0) {
            System.out.println("新增成功");
        } else {
            System.out.println("新增失敗");
        }
    } catch (SQLException e) {
        e.printStackTrace();
    } finally {

        try {
            if (ps != null) {
                ps.close();
            }
            if (conn != null) {
                conn.close();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

// 修改使用者
public void update(Bm Bankm) {
    Connection conn = DBUtil.getConnection();
    PreparedStatement ps = null;
    String sql = "update journal set zz=? where id=?";
    try {
        ps = conn.prepareStatement(sql);
        ps.setString(1, Bankm.getZz());
        ps.setInt(2, Bankm.getId());
        int a = ps.executeUpdate();
        if (a > 0) {
            System.out.println("修改成功");
        } else {
            System.out.println("修改失敗");
        }
    } catch (SQLException e) {
        e.printStackTrace();
    } finally {
        try {
            if (ps != null) {
                ps.close();
            }
            if (conn != null) {
                conn.close();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

// 刪除使用者
public void delete(int id) {
    Connection conn = DBUtil.getConnection();
    PreparedStatement ps = null;
    String sql = "DELETE FROM journal WHERE id=?";
    try {
        ps = conn.prepareStatement(sql);
        ps.setInt(1, id);
        int a = ps.executeUpdate();
        if (a > 0) {
            System.out.println("刪除成功");
        } else {
            System.out.println("刪除失敗");
        }
    } catch (SQLException e) {
        e.printStackTrace();
    } finally {
        try {
            if (ps != null) {
                ps.close();
            }
            if (conn != null) {
                conn.close();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}
 

}
7建立測試類（test.java）
public class test {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
BankDao bankd = new BankDao();
Bm bankm = new Bm();
while (true) {
System.out.println(“1.所有資訊”);
System.out.println(“2.新增資訊”);
System.out.println(“3.修改資訊”);
System.out.println(“4.刪除資訊”);
System.out.println(“請輸入功能”);
int a = sc.nextInt();
if (a == 1) {
ArrayList ar = new BankDao().getList();
for (Bm ne : ar) {
System.out.println(“編號:” + ne.getId()+”、” + “日期:” + ne.getRq()+”、”
+ “內容:” + ne.getNr()+”、” + “作者:” + ne.getZz()+”、” + “天氣:”
+ ne.getTq()+”、” + “標題:” + ne.getBt());
}
}
else if(a==2){
System.out.println(“請輸入日期:”);
bankm.setRq(sc.next());
System.out.println(“請輸入內容:”);
bankm.setNr(sc.next());
System.out.println(“請輸入作者”);
bankm.setZz(sc.next());
System.out.println(“請輸入天氣”);
bankm.setTq(sc.next());
System.out.println(“請輸入標題”);
bankm.setBt(sc.next());
bankd.inset(bankm);
}else if(a==3){
System.out.println(“請輸入要修改的使用者編號”);
bankm.setId(sc.nextInt());
System.out.println(“請輸入要修改的使用者名稱”);
bankm.setZz(sc.next());
bankd.update(bankm);
}else if(a==4){
System.out.println(“請輸入要刪除的使用者編號”);
int id=sc.nextInt();
bankd.delete(id);
}else{
System.out.println(“程式開發中：”);
}
}
}
}