remkop/picocli
Picocli
picocli is a command line interface development framework and argument parser for JVM-based applications. It maps command line options and positional parameters to strongly typed Java methods and fields using a declarative, annotation-based model.
The framework provides specific support for native image compilation, producing the reflection and resource configuration files necessary to build standalone binaries with reduced startup overhead. It further distinguishes itself with a dedicated system for generating shell autocompletion scripts and an ANSI terminal stylizer for applying colors and styles to output.
The project covers a broad range of terminal application capabilities, including hierarchical command dispatch for nested subcommands, automated generation of usage help and man pages, and interactive shell implementation with user prompts. It also includes infrastructure for dependency injection through custom factories, plugin-based type conversion, and the processing of external argument files.
Features
- Command Line Argument Parsers - Implements a powerful parser that converts raw shell input into structured Java objects based on defined requirements.
- Command Line Argument Parsing - Converts raw terminal input into strongly typed Java objects using named options and positional parameters.
- Command-Line Interface Development - Provides a framework for building terminal applications that map arguments and options to strongly typed Java data.
- Nested Command Structures - Creates hierarchical command structures that allow users to navigate complex toolsets through sub-levels.
- Command Hierarchies - Executes nested command hierarchies based on user input using aliases and lazy instantiation.
- AOT Metadata Generation - Produces the reflection and resource configuration files necessary to build standalone binaries with reduced startup overhead.
- Annotation-Based Model Mapping - Implements a declarative model that maps command line options and parameters to strongly typed Java fields using annotations.
- Hierarchical Command Dispatch - Supports hierarchical command dispatch for complex toolsets with nested subcommands.
- CLI Command Mapping - Maps command line arguments and options directly to specific methods and fields for automated execution.
- Reflection-Based Population - Uses reflection to populate typed fields in command objects from raw string arguments during the parsing phase.
- Argument Grouping - Groups related options to enforce mutual exclusivity or require that certain parameters appear together.
- CLI Type Converters - Transforms command line strings into complex data types using built-in converters or custom implementation classes.
- Type Conversion Registries - Implements a registry of interchangeable converter classes to transform command line strings into complex Java types.
- Native Binary Optimizations - Offers specific support for GraalVM native image compilation to create fast-starting standalone binaries.
- CLI Documentation Generation - Automatically produces formatted usage help, man pages, and technical documentation from command definitions.
- Recursive Argument File Parsing - Supports reading options from external files to bypass operating system command line length limits.
- External Argument File Processing - Reads input from external files to bypass operating system limits on command line length.
- Help Generators - Produces formatted help messages with synopses and option lists that adapt to terminal width.
- Interactive CLI Prompts - Provides interactive CLI prompts for collecting user input, including secure fields for passwords.
- Interactive Shells - Implements persistent interactive shell sessions combining command parsing with real-time tokenization.
- Man Page Generation - Automatically generates Unix man pages and other documentation formats from CLI definitions.
- Native AOT Compilation - Enables compilation into standalone binaries to eliminate runtime startup overhead and increase speed.
- Shell Autocompletion Scripts - Generates shell autocompletion scripts to provide interactive suggestions for options and subcommands.
- Shell Completion Generators - Generates context-sensitive shell autocompletion scripts for options and subcommands across various terminal shells.
- Native Compilation Metadata - Produces reflection and resource configuration files necessary for ahead-of-time native binary compilation.
- Native Image Compatibility Tools - Builds the command model at compile time to ensure full compatibility with native image compilers.
- Executable Interface Frameworks - Enables the creation of command line tools that operate either within or independently of a runtime environment.
- CLI - Restricts options by defining mutual exclusivity or specifying exact counts and ranges for parameters.
- Terminal Color Formatting - Provides a dedicated ANSI terminal stylizer for applying colors and styles to text output.
- Terminal Styling - Applies ANSI colors and styles to terminal output using markup codes for visual emphasis.
- Java CLI Frameworks - Modern framework for building user-friendly CLI apps.
- Scripting Tools - Framework for building feature-rich command-line interfaces.
