DistCp Driver
The DistCp Driver components are responsible for:
Parsing the arguments passed to the DistCp command on the command-line, via:
OptionsParser
DistCpOptionsSwitch
Assembling the command arguments into an appropriate DistCpOptions object, and initializing DistCp. These arguments include:
Source-paths
Target location
Copy options (e.g. whether to update-copy, overwrite, which file attributes to preserve, etc.)
Orchestrating the copy operation by:
Invoking the copy-listing generator to create the list of files to be copied.
Setting up and launching the Hadoop MapReduce job to carry out the copy.
Based on the options, either returning a handle to the Hadoop MapReduce job immediately, or waiting until completion.
The parser elements are executed only from the command-line (or if DistCp::run() is invoked). The DistCp class may also be used programmatically, by constructing the DistCpOptions object and initializing a DistCp object appropriately.