Clad User Manual

Internal

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Overview

The framework scans the command line looking for the first argument that can be mapped to a command.

The mapping process involves scanning the classpath and looking for classes implementing the Command interface. The current version does not introspect all classes, but just those whose simple class name match the following pattern: <commandName>Command.

All arguments between the wrapper name and the command name are interpreted as global options.

All arguments following the command name are interpreted as command options.

   wrapper [global-options] command [command-options]

Options

The options use the GNU command line convention:

 -o <value> | --option=<value>

Configuration File

Each command line option has a configuration file correspondent. Command line value takes precedence over the configuration file value.

Implementing a Command Line Application

Implement [ApplicationRuntime] interface.

Implementing a Command

Implement the Command interface.

The implementation class must be named <command-name>Command.

Example: PrintCommand will be matched to the "print" command. BusinessScenarioCommand will be matched to the "business-scenario" command.

Relationship between Command and ApplicationRuntime

If a specific command does not need an application runtime instance (thus the framework is not required to instantiate an application runtime for it), the Command.needsRuntime() implementation must return false. By default CommandBase.needsRuntime() returns true.

In-Line Command Help

If a text file named <command-name>.txt is placed in the same package as the command implementation class, the framework will send the content of the file to stdout when in-line command help is requested:

    <wrapper> --help <command>