我编写了一个 servlet 程序，我希望它连接到我的 Oracle 数据库，但它给了我一个错误。我正在使用 Eclipse Helios、Tomcat 6.0.37、Oracle 11g (11.2.0.1.0)、ojdbc6.jar（在服务器项目的运行配置中添加）。我能够通过 SQL Plus 接口连接到数据库，甚至可以从 Eclipse 的数据库开发角度启动连接。但是当我尝试通过我的 servlet 连接时，我收到错误。对于我的 servlet，我使用端口号 9090，对于数据库，我使用默认端口号 1521。
java.sql.SQLException: The Network Adapter could not establish the connection
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:412)
at oracle.jdbc.driver.PhysicalConnection.<init>(PhysicalConnection.java:531)
at oracle.jdbc.driver.T4CConnection.<init>(T4CConnection.java:221)
at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:32)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:503)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at com.android.collegenotificationsystem.RegistrationServlet.doGet(RegistrationServlet.java:43)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:606)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Unknown Source)
Caused by: oracle.net.ns.NetException: The Network Adapter could not establish the connection
at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:359)
at oracle.net.resolver.AddrResolution.resolveAndExecute(AddrResolution.java:422)
at oracle.net.ns.NSProtocol.establishConnection(NSProtocol.java:672)
at oracle.net.ns.NSProtocol.connect(NSProtocol.java:237)
at oracle.jdbc.driver.T4CConnection.connect(T4CConnection.java:1042)
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:301)
... 21 more
Caused by: java.net.ConnectException: Connection refused: connect
at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)
at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at oracle.net.nt.TcpNTAdapter.connect(TcpNTAdapter.java:141)
at oracle.net.nt.ConnOption.connect(ConnOption.java:123)
at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:337)
... 26 more
这是我建立连接的代码：
Class.forName("oracle.jdbc.OracleDriver");
Connection con = (Connection) DriverManager.getConnection( "jdbc:oracle:thin:@localhost:1521:orcl","username","password");
我尝试执行 lsnrctl stat 命令，结果如下：
LSNRCTL for 32-bit Windows: Version 11.2.0.1.0 - Production on 03-AUG-2013 16:08
:46
Copyright (c) 1991, 2010, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1521)))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for 32-bit Windows: Version 11.2.0.1.0 - Produ
ction
Start Date 03-AUG-2013 12:14:19
Uptime 0 days 3 hr. 54 min. 28 sec
Trace Level off
Security ON: Local OS Authentication
SNMP OFF
Listener Parameter File C:\app\Owner\product\11.2.0\dbhome_1\network\admin\lis
tener.ora
Listener Log File c:\app\owner\diag\tnslsnr\Owner-PC\listener\alert\log.
xml
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(PIPENAME=\\.\pipe\EXTPROC1521ipc)))
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=127.0.0.1)(PORT=1521)))
Services Summary...
Service "CLRExtProc" has 1 instance(s).
Instance "CLRExtProc", status UNKNOWN, has 1 handler(s) for this service...
Service "orcl.168.1.56" has 1 instance(s).
Instance "orcl", status READY, has 1 handler(s) for this service...
Service "orclXDB.168.1.56" has 1 instance(s).
Instance "orcl", status READY, has 1 handler(s) for this service...
The command completed successfully
这些是我的 tnsnames.ora 文件的内容：
LISTENER_ORCL =
(ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))
ORACLR_CONNECTION_DATA =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
)
(CONNECT_DATA =
(SID = CLRExtProc)
(PRESENTATION = RO)
)
)
ORCL =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = orcl.168.1.56)
)
)
任何帮助，将不胜感激。提前致谢。
