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Getting Started

Requirements

  • iPhone or iPad (device validation targets recent iOS)
  • A Java ME .jar you are legally allowed to run
  • A development build of CoreJ2 (App Store release pending)

Install a game

  1. Open CoreJ2.
  2. Use the library import flow to select a .jar.
  3. The Import Engine reads the manifest, computes a content hash, rejects duplicates, and extracts artwork when present.
  4. The title appears in your library.

Launch

  1. Tap a game in the library.
  2. The Emulator Bridge starts a session through RuntimeHost → PlatformBootstrap.
  3. Wait for the first LCD frame.
  4. Use the virtual keypad and/or touch surface.

Saves (RMS)

MIDP RecordStore data is written under:

Documents/JavaOne/Saves/<game-uuid>/rms/...

Do not rely on relative ./rms/ paths from desktop FreeJ2ME docs — CoreJ2 configures a sandbox dataPath per game.

Tips

  • Prefer titles listed on the Compatibility page for first tests.
  • If a launch fails, leave the emulator and try again; relaunch recovery was hardened in Epic 11.
  • Audio may be silent — MMAPI validation is still upcoming.

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