JDBC Boilerplate

public class Student
{
  private Integer studId;
  private String name;
  private String email;
  private Date dob;
  // setters and getters
}

public Student findStudentById(int studId)
{
  Student student = null;
  Connection conn = null;
  try{
    //obtain connection
    conn = getDatabaseConnection();
    String sql = "SELECT * FROM STUDENTS WHERE STUD_ID=?";
    //create PreparedStatement
    PreparedStatement pstmt = conn.prepareStatement(sql);
    //set input parameters
    pstmt.setInt(1, studId);
    ResultSet rs = pstmt.executeQuery();
    //fetch results from database and populate into Java objects
    if(rs.next()) {
      student = new Student();
      student.setStudId(rs.getInt("stud_id"));
      student.setName(rs.getString("name"));
      student.setEmail(rs.getString("email"));
      student.setDob(rs.getDate("dob"));
    }
  } catch (SQLException e){
    throw new RuntimeException(e);
  }finally{
    //close connection
    if(conn!= null){
      try {
        conn.close();
      } catch (SQLException e){ }
    }
  }
  return student;
}

public void createStudent(Student student)
{
  Connection conn = null;
  try{
    //obtain connection
    conn = getDatabaseConnection();
    String sql = "INSERT INTO STUDENTS(STUD_ID,NAME,EMAIL,DOB)
    VALUES(?,?,?,?)";
    //create a PreparedStatement
    PreparedStatement pstmt = conn.prepareStatement(sql);
    //set input parameters
    pstmt.setInt(1, student.getStudId());
    pstmt.setString(2, student.getName());
    pstmt.setString(3, student.getEmail());
    pstmt.setDate(4, new
    java.sql.Date(student.getDob().getTime()));
    pstmt.executeUpdate();
  } catch (SQLException e){
    throw new RuntimeException(e);
  }finally{
    //close connection
    if(conn!= null){
    try {
      conn.close();
      } catch (SQLException e){ }
    }
  }
}

protected Connection getDatabaseConnection() throws SQLException
{
  try{
    Class.forName("com.mysql.jdbc.Driver");
    return DriverManager.getConnection
    ("jdbc:mysql://localhost:3306/test", "root", "admin");
  } catch (SQLException e){
    throw e;
  } catch (Exception e){
    throw new RuntimeException(e);
  }
}

上一篇:.net core build docker image


下一篇:bzoj 4444: [Scoi2015]国旗计划