interbase 数据连接问题

我再本地配置了interbase服务
连接代码为String url = "jdbc:interbase://localhost/D:\\insta\\ZT0002-1.gdb"; 
Class.forName("interbase.interclient.Driver"); 
Connection conn = DriverManager.getConnection( url, "sysdba", "masterkey" ); 但是提示
Exception in thread "main" interbase.interclient.CommunicationException: [interclient] Communication error: A socket exception occurred while trying to establish a socket connection to server localhost.
The message of the SocketException is "Connection refused: connect".
See API reference for exception interbase.interclient.CommunicationException
at interbase.interclient.JDBCNet.establishSocketStreams(Unknown Source)
at interbase.interclient.JDBCNet.<init>(Unknown Source)
at interbase.interclient.Connection.connect(Unknown Source)
at interbase.interclient.Connection.<init>(Unknown Source)
at interbase.interclient.Driver.connect(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at com.suray.connection.ConnectionTest.main(ConnectionTest.java:15)
请问下问题具体出在什么地方