# Changelog

All notable changes to NetStatusBus are documented here.
The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
and the project aims to follow [Semantic Versioning](https://semver.org/) from 1.0.0 on.

## [Unreleased]

### Changed

- `MethodManager` and `NetworkCallbackImpl` are no longer public: both are package-private `final` classes (same style as `DefaultNetworkCallbackImpl`). They were never meant as supported API. `MethodManager` fields are `final` and setters are removed.
- `Constrants` (misspelled leftover used only by the sample) is `@Deprecated`. It is not part of the supported API; apps should use their own log tag / request codes. `LOG_TAG` and `SETTING_REQUEST_CODE` remain for binary compatibility. The sample app now uses a local `TAG` instead.

### Fixed

- If a `@NetSubscribe` method called `unregister` on its own subscriber (or another callback removed it) mid-dispatch, later annotated methods on that same subscriber could still run for the same event — for example a parent-class method after a child method that had already unregistered. Each method is now re-checked against the live observer list before invoke, matching the existing per-listener `contains` guard. Other subscribers are unaffected.
- When a VPN does not declare its underlying transport (mostly Android 6.0 to 8.1) and both Wi-Fi and always-on mobile data are connected, the type under the VPN depended on the order the system listed networks, so it could be reported as `MOBILE` while the device was on Wi-Fi. It is now chosen with the same priority as everywhere else (Wi-Fi, then mobile, then Ethernet).
- If two network callbacks reported changes at almost the same moment, the newer change could reach the main thread first and the older one second, so subscribers, listeners and `getNetTypeLiveData()` ended up on an outdated type while `getCurrentNetType()` already had the new one. An older change that arrives after a newer one is now dropped. The "only if changed" check and the update are also done in one step, so the same new type reported twice at once is delivered once, and the `WIFI`/`MOBILE` mode filters compare against the type subscribers actually received last.

### Documentation

- English Javadoc for the whole public API surface users touch first: `NetStatusBus` (class overview, `init`, `register`, `unregister`, `getNetTypeLiveData`, ...), `@NetSubscribe` (signature rules, superclass lookup, threading, example), `OnNetTypeChangeListener`, `NetType`, `Mode`, `MobileGeneration` and `NetworkUtils` (every query, the `Context` overloads that work without `init`, and `openSetting`). Chinese text is kept next to it. IDEs show it from the published sources jar.

### Tests

- `UnregisterDuringDispatchTest`: self-unregister skips remaining inherited methods in the same event; unregistering another subscriber in a callback skips them for that event; other subscribers still receive.
- Override-dedupe: when a child class overrides a parent method with the same signature and both declare `@NetSubscribe`, only the child's method is kept and invoked once (`NetStatusReceiverTest.overridingSameSignatureKeepsOnlyChildMethod`).
- `OutOfOrderDeliveryTest` reproduces a newer change being queued before an older one and checks that nobody is left on the older type or gets the same type twice.
- `ModeMatrixTest` checks every `Mode` against every network transition (Wi-Fi, mobile, Ethernet, none) and against the initial callback on `register`, so the documented mode table cannot drift silently.
- `VpnUnderlyingTypeTest` covers how the type under a VPN is picked, and `NetworkUtilsTest` now checks every `TelephonyManager.NETWORK_TYPE_*` value (0 to 20) against its 2G/3G/4G/5G generation.
- `NetworkUtilsTest` covers `findActivity` walking `ContextWrapper` / `ContextThemeWrapper` chains (including nested wrappers), returning null for an Application or a wrapper around a non-Activity, and stopping on a self-referential wrapper or a cycle without hanging.

### Sample app

- `MainActivity` now shows `NetworkUtils` in use: a details line with the current type, internet availability, VPN and mobile generation, and an "Open Wi-Fi settings" button that uses `openSetting(this, requestCode)` and refreshes the details in `onActivityResult`. A `Mode.AUTO` subscriber handles Ethernet, which the mode-filtered methods could not show. The button that opens the Fragment demo is now called `btn_to_fragment` instead of the misleading `btn_to_setting`.

## [1.1.0] - 2026-10-30

### Added

- `NetStatusBus.addListener(OnNetTypeChangeListener)` / `removeListener(...)`: an annotation-free, reflection-free callback for Java and Kotlin. It receives the current type right away and then every change on the main thread, including while the UI is in the background (unlike `LiveData`). `addListener(listener, LifecycleOwner)` removes it automatically on `DESTROYED`. A listener that throws is logged and does not affect other listeners or subscribers.

- `NetworkUtils.getNetType(Context)`, `isNetworkAvailable(Context)`, `isVpnActive(Context)` and `getMobileGeneration(Context)`: the same checks without calling `init` first (for example in a `BroadcastReceiver`, a WorkManager worker, or another library). Only the application context is kept.

- `NetStatusBus.getCurrentNetType()`: the type the bus last delivered, read from a cached field without querying the system (any thread). `NetStatusBus.isInitialized()` tells whether `init` has been called.

### Changed

- Using the bus or a no-argument `NetworkUtils` method before `init` now throws `IllegalStateException` with a message that explains the fix, instead of a bare `RuntimeException("application is empty")`; `register` and `addListener` called before `init` now throw the same `IllegalStateException` instead of `IllegalArgumentException`. `IllegalStateException` is a `RuntimeException`, so existing `catch` blocks still work.
- `unregisterAllObserver()` also removes listeners added with `addListener`.

### Fixed

- Registering the same subscriber from several threads at the same time could add it twice, so every network change was delivered to it twice. Registration and unregistration now share a lock; dispatch stays lock-free.
- Calling `register` or `addListener` off the main thread while the network was changing could deliver the "current type" callback after a newer change had already been delivered, so the subscriber or listener ended up on an outdated type until the next change (`getNetTypeLiveData()` was not affected). The initial callback is now skipped when a newer change has already been delivered.

## [1.0.0] - 2026-10-23

First release published through JitPack:
`implementation 'com.github.sunyatas:NetStatusBus:1.0.0'`.

### Added
- `NetStatusBus.getNetTypeLiveData()`: observe the network type as `LiveData<NetType>` without
  annotations or reflection (pure Java; Kotlin users can call `asFlow()`).
- `register(subscriber, LifecycleOwner)`: registers a subscriber and unregisters it automatically
  when the owner reaches `DESTROYED`.
- `NetType.ETHERNET` for wired connections, and `NetworkUtils.isVpnActive()`. A VPN is reported as
  the type of its underlying network (#13).
- `NetworkUtils.getMobileGeneration()` returns 2G/3G/4G/5G. It is opt-in: the host app must hold
  `READ_PHONE_STATE`, otherwise it returns `UNKNOWN` (#12).
- Consumer R8/ProGuard rules that keep `@NetSubscribe` methods, so minified apps work without extra
  configuration.
- JitPack publishing (`jitpack.yml`, `maven-publish` release publication with sources jar).
- GitHub Actions CI: debug build, unit tests, a minified sample release build that checks the
  consumer rules, and a `publishToMavenLocal` check that mirrors the JitPack build.
- Unit tests for dispatching, mode filtering, lifecycle binding, weak references, method validation,
  subscriber exceptions and the default-network tracker.
- Apache-2.0 license, English README with a Chinese translation (`README.zh-CN.md`), and this changelog.

### Changed
- Migrated to AndroidX; `compileSdk` 35, Android Gradle Plugin 8, JDK 17 to build. `minSdk` stays 21.
- Network type is derived from `NetworkCapabilities` instead of the deprecated `NetworkInfo`.
- On Android 7.0+ the library follows the system default network via
  `registerDefaultNetworkCallback`, so a switch (for example Wi-Fi to mobile) is reported
  immediately and a late `onLost` for the old network is ignored (#4, #11).
- `Mode.WIFI` / `Mode.MOBILE` subscribers are only called when that network itself connects or
  disconnects, not when an unrelated network drops (#7, #9).
- Subscriber methods are always invoked on the main thread, and the subscriber registry is
  thread-safe (#5).
- Subscribers are held through weak references, so a forgotten `unregister` no longer leaks an
  Activity or Fragment.
- `@NetSubscribe` methods declared in superclasses are discovered, and the lookup is cached per class.
- `NetworkUtils.isNetworkAvailable()` no longer requires the network to be `VALIDATED` on API 23+.
- `NetworkUtils.openSetting()` honors its `requestCode` and also works with a non-Activity `Context`.
- Exceptions thrown by a subscriber are logged with `Log.e` (tag `NetStatusBus`) with the real cause
  and `Class#method`; other subscribers are still notified.

### Fixed
- After turning Wi-Fi off the library could still report `WIFI` (#6).
- No network callback was registered on API 21, and calling `init()` twice registered it twice.
- The library manifest now declares `ACCESS_NETWORK_STATE` itself.

### Behavior notes when upgrading from the 2019 Bintray/JCenter builds
- The Maven coordinates changed from the defunct Bintray artifact to JitPack
  (`com.github.sunyatas:NetStatusBus`).
- `register()` now throws `IllegalArgumentException` when a `@NetSubscribe` method's parameter is
  not `NetType` (or a supertype of it), including methods inherited from a superclass. Before, such
  a method was accepted and failed only when an event was dispatched. Methods with more than one
  parameter or a non-void return type were already rejected.
- Callbacks always arrive on the main thread.

[Unreleased]: https://github.com/sunyatas/NetStatusBus/compare/v1.1.0...master
[1.1.0]: https://github.com/sunyatas/NetStatusBus/compare/v1.0.0...v1.1.0
[1.0.0]: https://github.com/sunyatas/NetStatusBus/compare/6aaadb4...v1.0.0