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++ // Copyright (C) 2021 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
++ #include <QtCore/qglobal.h>
++ #include <QtCore/qdebug.h>
++
++ #if defined(Q_QDOC) || defined(Q_OS_ANDROID)
++
++ #include <QtCore/qjniobject.h>
++ #include <QtCore/qjnitypes.h>
++
++ //! [QJniObject scope]
++ void functionScope()
++ {
++ QString helloString("Hello");
++ jstring myJString = 0;
++ {
++ QJniObject string = QJniObject::fromString(helloString);
++ myJString = string.object<jstring>();
++ }
++
++ // Ops! myJString is no longer valid.
++ QString myQtString = QJniObject(myJString).toString();
++ }
++ //! [QJniObject scope]
++
++ //! [C++ native methods]
++ static void fromJavaOne(JNIEnv *env, jobject thiz, jint x)
++ {
++ Q_UNUSED(env);
++ Q_UNUSED(thiz);
++ qDebug() << x << "< 100";
++ }
++
++ static void fromJavaTwo(JNIEnv *env, jobject thiz, jint x)
++ {
++ Q_UNUSED(env);
++ Q_UNUSED(thiz);
++ qDebug() << x << ">= 100";
++ }
++
++ void foo()
++ {
++ // register the native methods first, ideally it better be done with the app start
++ const JNINativeMethod methods[] =
++ {{"callNativeOne", "(I)V", reinterpret_cast<void *>(fromJavaOne)},
++ {"callNativeTwo", "(I)V", reinterpret_cast<void *>(fromJavaTwo)}};
++ QJniEnvironment env;
++ env.registerNativeMethods("my/java/project/FooJavaClass", methods, 2);
++
++ // Call the java method which will calls back to the C++ functions
++ QJniObject::callStaticMethod<void>("my/java/project/FooJavaClass", "foo", "(I)V", 10); // Output: 10 < 100
++ QJniObject::callStaticMethod<void>("my/java/project/FooJavaClass", "foo", "(I)V", 100); // Output: 100 >= 100
++ }
++ //! [C++ native methods]
++
++ #if 0 // Java code
++ //! [Java native methods]
++ class FooJavaClass
++ {
++ public static void foo(int x)
++ {
++ if (x < 100)
++ callNativeOne(x);
++ else
++ callNativeTwo(x);
++ }
++
++ private static native void callNativeOne(int x);
++ private static native void callNativeTwo(int x);
++
++ }
++ //! [Java native methods]
++ #endif
++
++ #endif