# java-sdk

**Repository Path**: alamhubb/java-sdk

## Basic Information

- **Project Name**: java-sdk
- **Description**: No description available
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2026-06-08
- **Last Updated**: 2026-06-08

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# Qin Java SDK JS

`@qin/java-sdk-js` is Qin's Java standard-library runtime for Java code lowered to JavaScript.

This package is intentionally a **Java 8 web subset**, not a full JDK clone. The goal is to support Java APIs that can run correctly inside JavaScript engines used by browsers, Node, and Vite-compatible tooling.

## Scope

Supported APIs should be:

- Deterministic in a JavaScript runtime.
- Implementable without JVM threads, native files, processes, class loaders, or OS-specific services.
- Needed by Qin Java-to-JS lowering or frontend Java experiments.
- Covered by focused smoke tests before being treated as supported.

## In Scope

Current and planned web-friendly areas:

- `java.lang`: strings, boxed primitives, enum, throwable hierarchy, `System` time/property subset, `StringBuilder`.
- `java.io.IOException`: exception type shape only, not filesystem behavior.
- `java.util`: `ArrayList`, `List`, `HashSet`, `Set`, `HashMap`, `Map`, `Arrays`, `Collections`, `Objects`, `Optional`, stream subset, atomic value helpers.
- `java.util.regex`: `Pattern` and `Matcher` backed by JavaScript `RegExp`, with documented semantic gaps where JS cannot match Java exactly.
- `java.time`: browser-safe date/time formatting subset.

## Out Of Scope

These are not frontend/web SDK promises:

- JVM threads, monitors, executors, and blocking concurrency.
- `java.io` and `java.nio.file` filesystem APIs, including virtual path shims. Qin tooling may use a separate runtime entry for those, but they are not part of the web SDK.
- Native filesystem mutation as real disk IO in browsers.
- Processes, shells, native libraries, JNI, `Unsafe`, class loaders, security manager APIs.
- Raw sockets or JVM networking APIs that cannot be faithfully represented in browser JavaScript.
- Full reflection. Qin may provide generated metadata only for classes it lowers.

## Rule

When generated JavaScript needs a missing Java API, add the smallest correct web-compatible implementation here and add a smoke test in Qin. Do not silently fake unsupported JVM/OS behavior as if it were a complete JDK implementation.