Java sql server数据库连接成功

import java.sql.Connection;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.DriverManager;
import java.sql.ResultSet;

     
public class JavaE2 {
    public static void main(String[] args) {
        Connection conn;
        Statement stmt;
        ResultSet rs;
        String url = "jdbc:sqlserver://localhost:1433;DatabaseName=test;";
        String sql = "select * from student";
        
        
            try {
                Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver"); 
                
            } catch (Exception ex) {
                System.out.println("数据库加载失败");
            }
        
        
        try {
            // 连接数据库
            conn = DriverManager.getConnection(url, "sa", "sa");
            // 建立Statement对象
            stmt = conn.createStatement();
            /**
             * Statement createStatement() 创建一个 Statement 对象来将 SQL 语句发送到数据库。
             */
            // 执行数据库查询语句
            rs = stmt.executeQuery(sql);
            /**
             * ResultSet executeQuery(String sql) throws SQLException 执行给定的 SQL
             * 语句，该语句返回单个 ResultSet 对象
             */
            while (rs.next()) {
                int id = rs.getInt("SID");
                String name = rs.getString("SNAME");
                int age = rs.getInt("SSEX");
                System.out.println("Sno:" + id + "	Same:" + name + "	Sage:" + age);
            }
            if (rs != null) {
                rs.close();
                rs = null;
            }
            if (stmt != null) {
                stmt.close();
                stmt = null;
            }
            if (conn != null) {
                conn.close();
                conn = null;
            }
        } catch (SQLException e) {
            e.printStackTrace();
            System.out.println("数据库连接失败");
        }
    }
}