java 用户名数据库_java中用户名与密码和数据库连接的两种方式

矫情吗；* 2022-11-03 10:42 13阅读 0赞

方法一String users=username.getText();

String psw=String.valueOf(password.getPassword());

/\*\*

\* 连接数据库

\*/

Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");

con = DriverManager

.getConnection(

"jdbc:microsoft:sqlserver://192.168.16.48:1433;DatabaseName=prise",

"sa", "sa");

stm = con.createStatement();

String sql = "select \* from users where username='"+users+"'" ;

rs = stm.executeQuery(sql);// 执行给定的sql语句，返回resultset对象

/\*\*

\* 判断

\*/

int i=0;

while (rs.next()) \{

i++;

if(psw.equals(rs.getString("password")))\{

System.out.println("存在此用户，用户名和密码分别是：");

System.out.println(rs.getString("username") + "/t"+ rs.getString("password"));

break;

if(!psw.equals(rs.getString("password")))\{

System.out.println("密码错误，请重新输入");

break;

if(i==0)\{

System.out.println("没有此用户");

方法二：

Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver");     con = DriverManager     .getConnection(       "jdbc:microsoft:sqlserver://192.168.16.48:1433;DatabaseName=prise",       "sa", "sa");     stm = con.createStatement(ResultSet.TYPE\_SCROLL\_INSENSITIVE,ResultSet.CONCUR\_UPDATABLE);     String sql="select \* from users";     rs = stm.executeQuery(sql);// 执行给定的sql语句，返回resultset对象     /\*\*      \* 判断      \*/          while (rs.next()) \{                 if(user.equals(rs.getString("username"))&&psw.equals(rs.getString("password")))\{       System.out.println("存在此用户，用户名和密码分别是：");       System.out.println(rs.getString("username") + "/t"+ rs.getString("password"));       break;      \}      if(user.equals(rs.getString("username"))&&!psw.equals(rs.getString("password")))\{       System.out.println("密码错误，请重新输入");       break;      \}     \}     if(rs.isAfterLast())\{      System.out.println("没有此用户请注册");     \}