com.microsoft.sqlserver.jdbc.SQLServerException: 通过端口 1433 连接到主机 localhost 的 TCP/IP 连接失败。错误:“Connection refused: connect。请验证连接属性。确保 SQL Server 的实例正在主机上运行，且在此端口接受 TCP/IP 连接，还要确保防火墙没有阻止到此端口的 TCP 连接。”。

at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDriverError(SQLServerException.java:190)

at com.microsoft.sqlserver.jdbc.SQLServerException.ConvertConnectExceptionToSQLServerException(SQLServerException.java:241)

at com.microsoft.sqlserver.jdbc.SocketFinder.findSocket(IOBuffer.java:2243)

at com.microsoft.sqlserver.jdbc.TDSChannel.open(IOBuffer.java:491)

at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectHelper(SQLServerConnection.java:1309)

at com.microsoft.sqlserver.jdbc.SQLServerConnection.login(SQLServerConnection.java:991)

at com.microsoft.sqlserver.jdbc.SQLServerConnection.connect(SQLServerConnection.java:827)

at com.microsoft.sqlserver.jdbc.SQLServerDriver.connect(SQLServerDriver.java:1012)

at java.sql.DriverManager.getConnection(DriverManager.java:582)

at java.sql.DriverManager.getConnection(DriverManager.java:185)

at com.test1.StuModel.init(StuModel.java:40)

at com.test1.StuModel.(StuModel.java:95)

at com.test1.StudentManagementSystem.(StudentManagementSystem.java:67)

at com.test1.StudentManagementSystem.main(StudentManagementSystem.java:39)