JNI: Implement QJniObject::className to get the name of the class if not set

If we construct the QJniObject from a jobject, then we know the jclass,
but not the class's name. If className is called while the stored name
is empty, get the name of the jclass and updated the stored value.

Change-Id: Ic3332a6da2dac1eb6842f90da1b9264398a43155
Reviewed-by: Juha Vuolle <juha.vuolle@qt.io>

1 files changed, 17 insertions, 0 deletions

diff --git a/tests/auto/corelib/kernel/qjniobject/tst_qjniobject.cpp b/tests/auto/corelib/kernel/qjniobject/tst_qjniobject.cpp
index 6f690f0091..36f6f5923e 100644
--- a/tests/auto/corelib/kernel/qjniobject/tst_qjniobject.cpp
+++ b/tests/auto/corelib/kernel/qjniobject/tst_qjniobject.cpp
@@ -42,6 +42,7 @@ private slots:
     void callObjectMethodTest();
     void stringConvertionTest();
     void compareOperatorTests();
+    void className();
     void callStaticObjectMethodClassName();
     void callStaticObjectMethod();
     void callStaticObjectMethodById();
@@ -300,6 +301,22 @@ void tst_QJniObject::compareOperatorTests()
     QVERIFY(!invalidStringObject.isValid());
 }
 
+void tst_QJniObject::className()
+{
+    const QString str("Hello!");
+    QJniObject jString = QJniObject::fromString(str);
+    {
+        QCOMPARE(jString.className(), "java/lang/String");
+        QCOMPARE(jString.toString(), str);
+    }
+
+    {
+        QJniObject strObject = QJniObject("java/lang/String", jString.object<jstring>());
+        QCOMPARE(strObject.className(), "java/lang/String");
+        QCOMPARE(strObject.toString(), str);
+    }
+}
+
 void tst_QJniObject::callStaticObjectMethodClassName()
 {
     QJniObject formatString = QJniObject::fromString(QLatin1String("test format"));