jdbc 连接数据库-MySQL-蒲公英云

jdbc 连接数据库-MySQL

墨蓝 2022-03-11 01:10 493阅读 0赞

static final String url = "jdbc:mysql://localhost:3306/lib?useUnicode=true&characterEconding=UTF-8";  
static final String user = "root";//自己的数据库的用户名  
static final String password = "123456";//自己的数据库的密码  
static Connection conn = null;  
static PreparedStatement ps = null;  
static ResultSet rs = null;

//——————————————————————————————查询操作：

public User findUser(User user) {

     Class.forName("com.mysql.jdbc.Driver");  
     conn = DriverManager.getConnection(url, user, password);
     String sql = "select \* from manager where name = ? and password = ? ";
        ps = conn.prepareStatement(sql);  
        ps.setString(1, user.getName());  
        ps.setString(2, user.getPassword());  
        rs = ps.executeQuery();

try {
while (rs.next()) {
if (rs.getString(“name”).equals(user.getName())
&& rs.getString(“password”).equals(user.getPassword())) {
// 关闭数据库连接
ps.close();
rs.close();
conn.close();

              //返回查询对象  
               return user;  
            \}  
        \}  
    \} catch (Exception e) \{  
        // TODO: handle exception  
    \}  
    return null;  
\}

//——————————————————————————————插入操作（删除、修改除了sql不一样其他都一样）：

public boolean saveUser(User user) {
boolean flag = false;

    Class.forName("com.mysql.jdbc.Driver");  
    conn = DriverManager.getConnection(url, user, password);  
    String sql = "insert into manager(name,password,tel) values(?,?,?)";  
    int i = 0;    
    ps = conn.prepareStatement(sql);
    ps.setString(1, user.getName());  
    ps.setString(2, user.getPassword());  
    ps.setString(3, user.getTel());  
    i = ps.executeUpdate();  
       //i>0表示执行成功  
        if (i > 0) \{  
            flag = true;  
        \}  
               ps.close();  
               conn.close();  
    return flag;  
\}