Maven launches copy each module's class directory into a snapshot and put
the snapshot on the classpath in place of the original. The originals came
from `module.join("target/classes")`, which on Windows reads
`...\app\target/classes`, while JDT LS reports `...\app\target\classes`.
Compared as text, the original was never removed, so every resource was on
the classpath twice; MyBatis then failed with "XML fragments parsed from
previous mappers already contains value", and any classpath* scan saw
duplicates. Mixed-language builds deduplicated their outputs the same way.
Launch class directories are joined per component, and classpath entries
are compared by a key that ignores the verbatim prefix, the separator,
trailing separators and, on Windows, case.
The IDE you know, rebuilt in Rust.
Download · Benchmark · Discord
https://github.com/user-attachments/assets/234dd54c-1255-4b3a-b35c-533d78d737c0
OpenIDEA brings the IntelliJ IDEA way of working — its keymap, its tool windows, its search-everything habits — to a native app with a Rust core.
Editor, code insight, debugger, Git, terminal, database and HTTP clients, for 60+ languages. Builds for macOS, Windows and Linux.
Benchmark
Opening freqtrade (Python, ~770 files) with warm caches, median of 5 runs:
| OpenIDEA | IntelliJ IDEA 2026.2.3 | |
|---|---|---|
| Window with the project | 0.9 s | 3.1 s |
| Ready (CPU settled) | 1.1 s | 13.2 s |
| Memory (USS, all processes) | 169 MB | 2011 MB |
| CPU time until ready | 2.4 s | 47.9 s |
| Idle CPU | 4 % of a core | 7 % of a core |
| Quit | 0.3 s | 5.9 s |
A release build of OpenIDEA from main and IDEA with default settings and plugins, on
Windows 11, 32-core AMD, 62 GB RAM.
IDEA analyses Python more deeply, so "ready" doesn't mean the same work on
both sides. Both are measured from the outside, the same way: see
perf/compare to run it on your machine and projects.
License
Apache 2.0. Bundled third-party assets are listed in THIRD_PARTY_LICENSES.md.
Not affiliated with JetBrains. IntelliJ IDEA is a trademark of JetBrains s.r.o.