SQLServerException：与主机的 TCPIP 连接失败

SQLServerException：与主机的 TCP/IP 连接失败

java
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class ConnectionExample {
    public static void main(String[] args) {
        String url = "jdbc:sqlserver://localhost:1433;databaseName=TestDB";
        String username = "sa";
        String password = "password";
        try {
            Connection conn = DriverManager.getConnection(url, username, password);
            System.out.println("成功连接到数据库！");
        } catch (SQLException e) {
            System.out.println("与主机的 TCP/IP 连接失败：" + e.getMessage());
        }
    }
}