不要忘了把數據庫驅動的jar包放入lib
1.dbConfig.properties文件內容如下:放入 src
#config file
driver=com.microsoft.jdbc.sqlserver.SQLServerDriver
url=jdbc:microsoft:sqlserver://127.0.0.1:1433;databasename=LogIn
username=sa
password=
2.DBUtil.java內容如下:
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ResourceBundle;
/**
* DBUtil這個類,獲取連接,關閉連接
* @author本人
*
*/
public class DBUtil {
private static String driver = "";
private static String url = "";
private static String username = "";
private static String password = "";
/**
* 顯示申明空結構
*
*/
public DBUtil() {
}
/**
* 讀取配置文件dbConfig.properties的信息
*
*/
public static void init() {
ResourceBundle res = ResourceBundle.getBundle("dbConfig");
driver = res.getString("driver");
url = res.getString("url");
username = res.getString("username");
password = res.getString("password");
}
/**
* 獲得數據庫連接對象
* @return
* @throws ClassNotFoundException
* @throws SQLException
*/
public static Connection getConnection() throws ClassNotFoundException, SQLException
{
init();
Connection conn=null;
Class.forName(driver);
conn=DriverManager.getConnection(url,username,password);
return conn;
}
/**
* 關閉數據庫連接對象
* @param rs
* @param stmt
* @param conn
*/
public static void closeAll(ResultSet rs,Statement stmt,Connection conn)
{
try {
if(null!=rs)
rs.close();
if(null!=stmt)
stmt.close();
if(null!=conn)
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
3.loginDao.java內容如下:
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import com.accp.vo.loginVO;
public class loginDao {
/**
* 顯示申明空結構
*
*/
public loginDao() {
}
/**
* 更具用戶名和密碼查找用戶對象是否存在
*
* @param username
* @param password
* @return
*/
public loginVO selectByNamePwd(String username, String password) {
loginVO loginVO = null;
Connection con = null;
PreparedStatement pstm = null;
ResultSet rs = null;
String sql = "SELECT * FROM login WHERE username = ? and password = ? ";
try {
con = DBUtil.getConnection();
pstm = con.prepareStatement(sql);
pstm.setString(1, username);
pstm.setString(2, password);
rs = pstm.executeQuery();
if (rs.next()) {
String uname = rs.getString(2);
String upwd = rs.getString(3);
loginVO = new loginVO(uname, upwd);
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
} finally {
// 關閉數據庫聯接
DBUtil.closeAll(rs, pstm, con);
}
return loginVO;
}
/**
* 查找用戶是否存在
* @param username
* @return
*/
public loginVO selectByName(String username) {
loginVO loginVO = null;
Connection con = null;
PreparedStatement pstm = null;
ResultSet rs = null;
String sql = "SELECT * FROM login WHERE username = ?";
try {
con = DBUtil.getConnection();
pstm = con.prepareStatement(sql);
pstm.setString(1, username);
rs = pstm.executeQuery();
if (rs.next()) {
String uname = rs.getString(2);
loginVO = new loginVO();
loginVO.setUsername(uname);
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
} finally {
// 關閉數據庫聯接
DBUtil.closeAll(rs, pstm, con);
}
return loginVO;
}
/**
* 註冊用戶
* @param username
* @param password
* @return
*/
public int insert(String username,String password)
{
int row=0;
Connection conn=null;
PreparedStatement pstm=null;
String sql="insert into login values(?,?)";
try {
conn=DBUtil.getConnection();
pstm=conn.prepareStatement(sql);
pstm.setString(1, username);
pstm.setString(2, password);
row=pstm.executeUpdate();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}finally
{
DBUtil.closeAll(null, pstm, conn);
}
return row;
}
public static void main(String[] args)
{
loginDao ld=new loginDao() ;
int i=0;
System.out.println(ld.insert("test2", "1234"));
}
}
4.loginVO.java內容如下:
public class loginVO {
private int uid;
private String username;
private String password;
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public int getUid() {
return uid;
}
public void setUid(int uid) {
this.uid = uid;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public loginVO() {
}
public loginVO(String username, String password) {
this.username = username;
this.password = password;
}
}
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