I get the following error when I run a java program:

```
Exception in thread "main" java.lang.UnsatisfiedLinkError: t2cPingDatabase
        at oracle.jdbc.driver.T2CConnection.t2cPingDatabase(Native Method)
        at oracle.jdbc.driver.T2CConnection.doPingDatabase(T2CConnection.java:503)
        at oracle.jdbc.driver.PhysicalConnection.pingDatabase(PhysicalConnection.java:4886)
        at oracle.jdbc.driver.PhysicalConnection.pingDatabase(PhysicalConnection.java:4899)
        at oracle.jdbc.pool.OracleImplicitConnectionCache.testDatabaseConnection(OracleImplicitConnectionCache.java:2174)
        at oracle.jdbc.pool.OracleImplicitConnectionCache.performPooledConnectionTask(OracleImplicitConnectionCache.java:1343)
        at oracle.jdbc.pool.OracleImplicitConnectionCache.doForEveryCachedConnection(OracleImplicitConnectionCache.java:1208)
        at oracle.jdbc.pool.OracleImplicitConnectionCache.refreshCacheConnections(OracleImplicitConnectionCache.java:1848)
        at oracle.jdbc.pool.OracleConnectionCacheManager.refreshCache(OracleConnectionCacheManager.java:480)
        at tkpjb7382521.refreshConnectionPool(tkpjb7382521.java:199)
        at tkpjb7382521.test(tkpjb7382521.java:115)
        at tkpjb7382521.run(tkpjb7382521.java:46)
        at sqlj.qa.harness.AppJdbcHarness.RunTestCase(AppJdbcHarness.java:158)
        at sqlj.qa.harness.AppJdbcHarness.main(AppJdbcHarness.java:79)

```

What could be the possible reason for this?