1 files changed, 133 insertions, 0 deletions
diff --git a/src/corelib/doc/snippets/jni/src_qjniobject.cpp b/src/corelib/doc/snippets/jni/src_qjniobject.cpp
new file mode 100644
index 0000000000..f3433134db
--- /dev/null
+++ b/src/corelib/doc/snippets/jni/src_qjniobject.cpp
@@ -0,0 +1,133 @@
+/****************************************************************************
+ **
+ ** Copyright (C) 2021 The Qt Company Ltd.
+ ** Contact: http://www.qt.io/licensing/
+ **
+ ** This file is part of the documentation of the Qt Toolkit.
+ **
+ ** $QT_BEGIN_LICENSE:BSD$
+ ** Commercial License Usage
+ ** Licensees holding valid commercial Qt licenses may use this file in
+ ** accordance with the commercial license agreement provided with the
+ ** Software or, alternatively, in accordance with the terms contained in
+ ** a written agreement between you and The Qt Company. For licensing terms
+ ** and conditions see https://www.qt.io/terms-conditions. For further
+ ** information use the contact form at https://www.qt.io/contact-us.
+ **
+ ** BSD License Usage
+ ** Alternatively, you may use this file under the terms of the BSD license
+ ** as follows:
+ **
+ ** "Redistribution and use in source and binary forms, with or without
+ ** modification, are permitted provided that the following conditions are
+ ** met:
+ **   * Redistributions of source code must retain the above copyright
+ **     notice, this list of conditions and the following disclaimer.
+ **   * Redistributions in binary form must reproduce the above copyright
+ **     notice, this list of conditions and the following disclaimer in
+ **     the documentation and/or other materials provided with the
+ **     distribution.
+ **   * Neither the name of The Qt Company Ltd nor the names of its
+ **     contributors may be used to endorse or promote products derived
+ **     from this software without specific prior written permission.
+ **
+ **
+ ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+ **
+ ** $QT_END_LICENSE$
+ **
+ ****************************************************************************/
+
+//! [Working with lists]
+QStringList getTrackTitles(const QJniObject &album) {
+    QStringList stringList;
+    QJniObject list = album.callObjectMethod("getTitles",
+                                             "()Ljava/util/List;");
+
+    if (list.isValid()) {
+        const int size = list.callMethod<jint>("size");
+        for (int i = 0; i < size; ++i) {
+            QJniObject title = list.callObjectMethod("get", "(I)Ljava/lang/Object;", i);
+            stringList.append(title.toString());
+        }
+    }
+    return stringList;
+}
+//! [Working with lists]
+
+//! [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.
+}
+//! [QJniObject scope]
+
+//! [Registering 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 registerNativeMethods() {
+    JNINativeMethod methods[] {{"callNativeOne", "(I)V", reinterpret_cast<void *>(fromJavaOne)},
+                               {"callNativeTwo", "(I)V", reinterpret_cast<void *>(fromJavaTwo)}};
+
+    QJniObject javaClass("my/java/project/FooJavaClass");
+    QJniEnvironment env;
+    jclass objectClass = env->GetObjectClass(javaClass.object<jobject>());
+    env->RegisterNatives(objectClass,
+                         methods,
+                         sizeof(methods) / sizeof(methods[0]));
+    env->DeleteLocalRef(objectClass);
+}
+
+void foo()
+{
+    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
+}
+
+//! [Registering native methods]
+
+//! [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]