# System top-level property

_System System
final

Internal system facade for the JetLeaf framework.

The `_System` class wraps a Properties implementation and delegates all environment-related method calls to it. It is the central access point for querying runtime information while also exposing system-level streams (`out`, `err`) and process management (exit).

This class is not intended to be used directly by end-users. Instead, it acts as the internal bridge between JetLeaf's runtime environment and the underlying system.

### Example

    final system = _System();
    system.setProperties(myProperties);

    // Delegated calls
    if (system.isDevelopmentMode()) {
      print('Running in dev mode');
    }

    // System streams
    system.out.writeln('Hello stdout');
    system.err.writeln('Hello stderr');

    // Exit process
    system.exit(0);

## Implementation

    final _System System = _System();