add null check for EnumWriteProtocol
Make the ParquetLoader.inputFormatCache HashMap a WeakHashMap in order to free memory for long running processes that do not leverage caching
use a new string in order to enforce weak reference on the key
use a new string in order to enforce weak reference on the key
use a new string in order to enforce weak reference on the key
use cascading 2.2.0
throw ParquetEncodingException
Merge pull request #205 from fs111/master

use cascading 2.2.0
Merge pull request #203 from Parquet/check_null_for_enum_write_protocol

add null check for EnumWriteProtocol
fix comment
fix comment, remove size
Merge pull request #204 from aaghevli/ParquetLoader.inputFormatCache

ParquetLoader.inputFormatCache as WeakHashMap