JDBC的增删改查

public List<Goddess> querry() throws SQLException{

Connection conn = JDBC.getConnection();

// 3.通过数据库的连接操作数据库，实现增删改查
Statement stmt = conn.createStatement();

ResultSet rs = stmt.executeQuery("select user_name,age from mk");
List<Goddess> gs =new ArrayList<>();
Goddess g =null;
while (rs.next()) {
g=new Goddess();
g.setUser_name(rs.getString("user_name"));
g.setAge( rs.getInt("age"));

gs.add(g);
}
return gs;
}

public void addGoddess(Goddess g) throws SQLException{

Connection conn = JDBC.getConnection();
String sql ="" +
"insert into mk "+
"(user_name,sex, age,birthday,email,mobile) "+
" value(?,?,?,?,?,?)";

PreparedStatement ptmt= conn.prepareStatement(sql);//加载mysql驱动程序
ptmt.setString(1, g.getUser_name());
ptmt.setInt(2, g.getSex());
ptmt.setInt(3, g.getAge());
ptmt.setDate(4, new java.sql.Date( g.getBirthday().getTime()));//注意date的包util和sql

ptmt.setString(5, g.getEmail());
ptmt.setString(6, g.getMobile());

ptmt.execute();
}

public void updateGoddess(Goddess g) throws SQLException{

Connection conn = JDBC.getConnection();
String sql =" " +
" update mk "+
" set user_name=?, sex=?,age=?,birthday=?,email=?,mobile=? "+
" where id =? ";

PreparedStatement ptmt= conn.prepareStatement(sql);//加载mysql驱动程序
ptmt.setString(1, g.getUser_name());
ptmt.setInt(2, g.getSex());
ptmt.setInt(3, g.getAge());
ptmt.setDate(4, new
java.sql.Date(g.getBirthday().getTime()));//注意date的包util和sql
ptmt.setString(5, g.getEmail());
ptmt.setString(6, g.getMobile());
ptmt.setInt(7, g.getId());
ptmt.execute();
}

public void delGoddess(Integer ID) throws SQLException{

Connection conn = JDBC.getConnection();
String sql =" " +
" delete from mk "+
" where id =? ";

PreparedStatement ptmt= conn.prepareStatement(sql);//加载mysql驱动程序

ptmt.setInt(1, ID);
ptmt.execute();
}