| Name | Description | Type | Package | Framework |
| ArArchiveEntry | Represents an archive entry in the ar format. | Class | org.apache.commons.compress.archivers.ar | Apache Commons |
| ArArchiveInputStream | Class | org.apache.commons.compress.archivers.ar | Apache Commons | |
| ArArchiveOutputStream | Class | org.apache.commons.compress.archivers.ar | Apache Commons | |
| ArchiveEntry | Represents an entry of an archive. | Interface | org.apache.commons.compress.archivers | Apache Commons |
| ArchiveException | Archiver related ExceptionSee Also:Serialized Form | Class | org.apache.commons.compress.archivers | Apache Commons |
| ArchiveInputStream | Archive input streams MUST override the InputStream. | Class | org.apache.commons.compress.archivers | Apache Commons |
| ArchiveOutputStream | Archive output stream implementations are expected to override the OutputStream. | Class | org.apache.commons.compress.archivers | Apache Commons |
| ArchiveStreamFactory | Factory to create Archive[In Out]putStreams from names or the first bytes of the InputStream. | Class | org.apache.commons.compress.archivers | Apache Commons |
| ArjArchiveEntry | An entry in an ARJ archive. | Class | org.apache.commons.compress.archivers.arj | Apache Commons |
| ArjArchiveEntry .HostOs | The known values for HostOs. | Class | org.apache.commons.compress.archivers.arj.ArjArchiveEntry | Apache Commons |
| ArjArchiveInputStream | Class | org.apache.commons.compress.archivers.arj | Apache Commons | |