Applications using oracle as a database in some scenario we used to get this error and there are several possible reasons for this exception.

Connection] [c3p0] NewPooledConnection close Exception.
java.sql.SQLException: No more data to read from socket
        at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:113) ~[ojdbc14.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
        at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:147) ~[ojdbc14.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
        at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:209) ~[ojdbc14.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
        at oracle.jdbc.driver.T4CMAREngine.unmarshalUB1(T4CMAREngine.java:1129) ~[ojdbc14.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
        at oracle.jdbc.driver.T4CMAREngine.unmarshalSB1(T4CMAREngine.java:1080) ~[ojdbc14.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
        at oracle.jdbc.driver.T4C7Ocommoncall.receive(T4C7Ocommoncall.java:106) ~[ojdbc14.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
        at oracle.jdbc.driver.T4CConnection.logoff(T4CConnection.java:468) ~[ojdbc14.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
        at oracle.jdbc.driver.PhysicalConnection.close(PhysicalConnection.java:1254) ~[ojdbc14.jar:Oracle JDBC Driver version - "10.2.0.5.0"]
        at com.mchange.v2.c3p0.impl.NewPooledConnection.close(NewPooledConnection.java:549) [c3p0.jar:0.9.1.2]
        at com.mchange.v2.c3p0.impl.NewPooledConnection.close(NewPooledConnection.java:234) [c3p0.jar:0.9.1.2]
        at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.destroyResource(C3P0PooledConnectionPool.java:470) [c3p0.jar:0.9.1.2]
        at com.mchange.v2.resourcepool.BasicResourcePool$1DestroyResourceTask.run(BasicResourcePool.java:964) [c3p0.jar:0.9.1.2]
        at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547) [c3p0.jar:0.9.1.2]
[distributor] 2015-07-14 12:14:24,059 CEST +0200 WARN  [com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#2] [BasicResourcePool] Failed to destroy resource: com.mchange.v2.c3p0.impl.NewPooledConnection@294ea944
java.sql.SQLException: Some resources failed to close properly while closing com.mchange.v2.c3p0.impl.NewPooledConnection@294ea944
        at com.mchange.v2.c3p0.impl.NewPooledConnection.close(NewPooledConnection.java:571) ~[c3p0.jar:0.9.1.2]

Possible Reasons:

1. Your running oracle instance might be killed or stopped working ,so you existing connection is not able to read any data.
2. There could be network issue between your application server and database server