| ByteArrayBuffer | A resizable byte array. |
| CharArrayBuffer | A resizable char array. |
| EncodingUtils | The home for utility methods that handle various encoding tasks. |
| EntityUtils | Static helpers for dealing with HttpEntitys. |
| ExceptionUtils | The home for utility methods that handle various exception-related tasks. |
| LangUtils | A set of utility methods to help produce consistent
equals and hashCode methods. |
| VersionInfo | Provides access to version information for HTTP components. |