Problem: Getting SQL Exception java.sql.SQLException: Protocol violation
Solution: I had researched various available solutions for this issue, however none of them solved my issue. I will first summarize some available solutions before presenting what solved the problem in a different way
Solution 1: DB password was showing an error ORA-28002: the password will expire within XX day. Reseting the password resolves the issue
Solution 2: use 64 bit VM. To use 64 bit VM pass argument -d64 as command line parameter to Java.
Solution 3: In My case, its the JVM Settings. Increasing the -Xmx<size> set maximum Java heap size
Increasing from -Xmx512M to -Xmx1024M resolved the issue as well