????2.????????????д???????????????????????????з?????????????????????????????з?????

public class UserDaoImpl implements IUserDao {
private Connection conn = null;
DBUtil db ;
public UserDaoImpl(){
db = new DBUtil();//?????????
conn = db.getConnection();// ??????????
}
public User Login(String username?? String pwd) {
//???????????????username  pwd????????
String sql = "select * from adduser where username = ? and password = ?";
//??????????????? state;
PreparedStatement state;
try {
//???state????????sql???
state = conn.prepareStatement(sql);
// ???state ????sql????е?????????????????磬?????????У??????????????????????username???????????password
state.setString(1?? username);
state.setString(2?? pwd);
//??в????????????ResultSet????r
ResultSet r = state.executeQuery();
if(r.next()){
//???????r.get??????????????????????????????????????????С????????????????user
User user = new User();
user.setId(r.getInt("id"));
user.setName(r.getString("name"));
user.setUsername(r.getString("username"));
user.setPwd(r.getString("password"));
user.setAge(r.getInt("age"));
user.setSex(r.getString("sex"));
return user;
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
db.closeConn(conn);
}
return null;//??????????????????????????????????????????????? ???????
}
//?????? id??????????????
public User QueryUser(int id) {
String sql = "select * from adduser where id = ?";
//???????????
PreparedStatement state;
try {
state = conn.prepareStatement(sql);
state.setInt(1?? id);
ResultSet r = state.executeQuery();
if(r.next()){
User user = new User();
user.setId(r.getInt("id"));
user.setName(r.getString("name"));
user.setUsername(r.getString("username"));
user.setPwd(r.getString("password"));
user.setAge(r.getInt("age"));
user.setSex(r.getString("sex"));
return user;
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
db.closeConn(conn);
}
return null;
}
//??????е???????
public ArrayList<User> QueryUserall() {
String sql = "select * from adduser";
//???????????
PreparedStatement state;
ArrayList<User> list = new ArrayList<User>();
try {
state = conn.prepareStatement(sql);
ResultSet r = state.executeQuery();
while(r.next()){
User user = new User();
user.setId(r.getInt("id"));
user.setName(r.getString("name"));
user.setUsername(r.getString("username"));
user.setPwd(r.getString("password"));
user.setAge(r.getInt("age"));
user.setSex(r.getString("sex"));
list.add(user);
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
db.closeConn(conn);
}
return list;
}
// ????????????????????????3??????1????????0??
public int UpdateUser(User user) {
String sql = "update adduser set name = ???username = ???password = ???sex = ???age = ? where id = ?";
//???????????
PreparedStatement state;
int r = 0;
try {
//???????????????????state?????state????????sql???????????setString??????? ?????
state = conn.prepareStatement(sql);
state.setString(1?? user.getName());
state.setString(2?? user.getUsername());
state.setString(3?? user.getPwd());
state.setString(4?? user.getSex());
state.setInt(5?? user.getAge());
state.setInt(6?? user.getId());
r = state.executeUpdate();//??и??·????????3??????????????????0??
} catch (SQLException e) {
e.printStackTrace();
}finally{
db.closeConn(conn);
}
return r;
}
public int addUser(User user) {
String sql = "insert into adduser(name??username??password??sex??age) values(?????????????)";
//???????????
PreparedStatement state;
boolean r = false;
try {
state = conn.prepareStatement(sql);
state.setString(1?? user.getName());
state.setString(2?? user.getUsername());
state.setString(3?? user.getPwd());
state.setString(4?? user.getSex());
state.setInt(5?? user.getAge());
r = state.execute(sql);
} catch (SQLException e) {
e.printStackTrace();
}finally{
db.closeConn(conn);
}
return r?1:0;
}
public int deletUser(int id) {
String sql = "delete from adduser where id = ?";
PreparedStatement state ;
boolean b = false;
try {
state = conn.prepareStatement(sql);
state.setInt(1?? id);
b = state.execute();
} catch (Exception e) {
}
return b?1:0;
}
}