java与sql2005直连 的问题

com.microsoft.sqlserver.jdbc.SQLServerException: 到主机 的 TCP/IP 连接失败。 java.net.ConnectException: Connection refused: connect
at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDriverError(Unknown Source)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectHelper(Unknown Source)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.loginWithoutFailover(Unknown Source)
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connect(Unknown Source)
at com.microsoft.sqlserver.jdbc.SQLServerDriver.connect(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at NewsFirstTitleDB1.main(NewsFirstTitleDB1.java:19)

SQL Server 2000

String driverName = "com.microsoft.jdbc.sqlserver.SQLServerDriver";
String dbURL = "jdbc:microsoft:sqlserver://localhost:1433; DatabaseName=sample";

而SQL Server 2005 中加载驱动和URL的语句则为

String driverName = "com.microsoft.sqlserver.jdbc.SQLServerDriver";
String dbURL = "jdbc:sqlserver://localhost:1433; DatabaseName=sample";

数据库联接有没打开。