Sql developer connection times out very frequently

Solution 1: (Didn't work)

1. Download oracle instant client
   http://www.oracle.com/technetwork/database/features/instant-client/index-097480.html
2. Unzip and put it somewhere within your directory
3. Within your Sql Developer, Tools – Preferences –> Database->Advanced
1. Check use oracle client 
2. Click on configure
1. client type: instant client
2. client location: C:\javapps\oraclexe\instantclient-basic-windows.x64-12.1.0.2.0\instantclient_12_1
4. Open sqlnet.ora file on server side and put this line
   SQLNET.EXPIRE_TIME=1
5. Restart your Sql Developer and server, if necessary

That’s it. The connection between Sql Developer and Oracle XE should be fine now.

Solution 2: (This worked for my environment)
This can be caused by and Out Of Bands (OOB) error in the jdbc driver on the network.To ignore this error, add this to sqldeveloper.conf file

AddVMOption -Doracle.net.disableOob=true