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// Copyright (C) 2025 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
/*!
\title Qt Jenny: Java Code Generator
\group qtjenny
\ingroup android
\brief Overview of Qt Jenny.
Qt Jenny translates Java APIs to Qt C++ wrappers, allowing Qt C++ programs
to invoke Java functionality. This is particularly useful on a
platform with Java system APIs, like Android.
\section1 Features
Qt Jenny's features:
\list
\li Generation of wrappers for any Java class.
\li Templated generation with customizable templates that can be changed to customize the C++ output.
\li Configurable generation that allows controlling the namespace
of the generated wrappers.
\li Support for generating code that uses QJniObject in the generated
code, therefore utilizing all the convenience QJniObject brings.
\endlist
\section1 Examples
See \l {QtJenny Demo} for an example how to use Qt Jenny.
\section1 How Qt Jenny works
Qt Jenny translates Java APIs to Qt C++ wrappers by the use of the following
building blocks:
\list
\li Kotlin code that imports the classes to be wrapped.
\li Annotations in that code that tell which classes to wrap.
\li A code generator that reads the annotations and generates the wrapper code.
\endlist
With these building blocks, the Qt project is then structured so
that there's a separate Gradle project for generating the
code that the Qt CMake project uses. The CMake project triggers the
code generation at project configuration time
(in other words, when you run CMake). For an application that
invokes methods but does not need to implement any callbacks,
a single code-generation project is enough. For an application
that uses both method invocations and interface callbacks, two generation
projects are needed: one for the method proxies and one for the
callback hierarchy. For an application that needs to extend
classes, three generation projects are needed: one for the method proxies,
one for the Java glue code, and one for the callback hierarchy.
The example code in \l {QtJenny Demo} uses three generation projects,
since it uses class extension.
\image qtjenny-sequence.drawio.svg {How it works}
\section1 Reference
//! TODO: Are there any references around code generation the reader could benefit from
\section1 Licenses and Attributions
Qt Jenny potentially contains third-party modules under the following
permissive licenses:
\annotatedlist attributions-qtjenny
*/
/*!
\page qtjenny-examples.html
\title Qt Jenny Examples
Qt Jenny examples:
\list
\li \l {QtJenny: Generating C++ proxy classes to access Android APIs}
\endlist
*/