一个简单的Java 连接SQL Server数据库连接驱动类

import java.sql.*;

/**
 * SQL Server数据库连接类
 * @author Administrator
 *
 */
public class Sqlsdc {

    static int a = 0;
    
    public Connection sqlsdc(String user, String pwd, String dn) {
        
        String url = "jdbc:sqlserver://localhost:1433;databaseName="+dn;
        final String driverClassName = "com.microsoft.sqlserver.jdbc.SQLServerDriver";
        @SuppressWarnings("unused")
        String userName = user;
        String password = pwd;
        
        //连接对象
        Connection con = null; 
        
        try {
            Class.forName(driverClassName);
            con = DriverManager.getConnection(url, user, password);
            //System.out.println("\n成功...\n");
        } catch (SQLException e) {
            System.err.println("\n发生错误，数据库服务未开启！");
            a=1;
        }catch (ClassNotFoundException e) {
            System.err.println("\n连接数据库失败！");
            e.printStackTrace();
        }
        return con;
        
    }
    
    //返回开启状态
    public int fail() {
        return a;
        
    }
    
    //关闭连接
    public void close(ResultSet rt, Statement st, Connection con) throws SQLException {
        
        if (rt!=null) {
            rt.close();
        }
        if (st!=null) {
            st.close();
        }
        if (con!=null) {
            con.close();
        }
        
        
    }
    
}