我们在应用程序中遇到数据库连接问题。重新启动后，它可以解决问题。但是，可能是什么原因。这是完整的堆栈跟踪，
2020-02-18 06:02:35,236 [Thread-0] ERROR DbConnection : Db error
java.sql.SQLRecoverableException: IO Error: The Network Adapter could not establish the connection
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:743)
at oracle.jdbc.driver.PhysicalConnection.connect(PhysicalConnection.java:666)
at oracle.jdbc.driver.T4CDriverExtension.getConnection(T4CDriverExtension.java:32)
at oracle.jdbc.driver.OracleDriver.connect(OracleDriver.java:566)
at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:677)
at java.sql/java.sql.DriverManager.getConnection(DriverManager.java:228)
at utils.DbConnection.getConnection(DbConnection.java:25)
at clientapplication.RequestAndResponseHistory.insertRequestAndResponseIntoDb(RequestAndResponseHistory.java:51)
at clientapplication.RequestAndResponseHistory.run(RequestAndResponseHistory.java:34)
Caused by: oracle.net.ns.NetException: The Network Adapter could not establish the connection
at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:470)
at oracle.net.resolver.AddrResolution.resolveAndExecute(AddrResolution.java:506)
at oracle.net.ns.NSProtocol.establishConnection(NSProtocol.java:595)
at oracle.net.ns.NSProtocolStream.negotiateConnection(NSProtocolStream.java:220)
at oracle.net.ns.NSProtocol.connect(NSProtocol.java:264)
at oracle.jdbc.driver.T4CConnection.connect(T4CConnection.java:1452)
at oracle.jdbc.driver.T4CConnection.logon(T4CConnection.java:496)
... 8 more
Caused by: java.net.BindException: Address already in use: connect
at java.base/java.net.PlainSocketImpl.waitForConnect(Native Method)
at java.base/java.net.PlainSocketImpl.socketConnect(PlainSocketImpl.java:107)
at java.base/java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:399)
at java.base/java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:242)
at java.base/java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:224)
at java.base/java.net.SocksSocketImpl.connect(SocksSocketImpl.java:403)
at java.base/java.net.Socket.connect(Socket.java:591)
at oracle.net.nt.TcpNTAdapter.connect(TcpNTAdapter.java:161)
at oracle.net.nt.ConnOption.connect(ConnOption.java:159)
at oracle.net.nt.ConnStrategy.execute(ConnStrategy.java:428)
... 14 more
但是在那段时间里，我们可以使用Sql Developer建立与数据库的连接。
这里可能是什么问题？我们如何避免呢？
这是连接字符串，
jdbc：oracle：thin：@SERVERNAME：1521 / test JDBC：https://mvnrepository.com/artifact/com.oracle/ojdbc7/12.1.0.2