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-rw-r--r--src/corelib/kernel/qjniobject.cpp779
1 files changed, 387 insertions, 392 deletions
diff --git a/src/corelib/kernel/qjniobject.cpp b/src/corelib/kernel/qjniobject.cpp
index dfb0dbd36d..8244a4390f 100644
--- a/src/corelib/kernel/qjniobject.cpp
+++ b/src/corelib/kernel/qjniobject.cpp
@@ -1,41 +1,5 @@
-/****************************************************************************
-**
-** Copyright (C) 2021 The Qt Company Ltd.
-** Contact: https://www.qt.io/licensing/
-**
-** This file is part of the QtCore module of the Qt Toolkit.
-**
-** $QT_BEGIN_LICENSE:LGPL$
-** 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.
-**
-** GNU Lesser General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU Lesser
-** General Public License version 3 as published by the Free Software
-** Foundation and appearing in the file LICENSE.LGPL3 included in the
-** packaging of this file. Please review the following information to
-** ensure the GNU Lesser General Public License version 3 requirements
-** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
-**
-** GNU General Public License Usage
-** Alternatively, this file may be used under the terms of the GNU
-** General Public License version 2.0 or (at your option) the GNU General
-** Public license version 3 or any later version approved by the KDE Free
-** Qt Foundation. The licenses are as published by the Free Software
-** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
-** included in the packaging of this file. Please review the following
-** information to ensure the GNU General Public License requirements will
-** be met: https://www.gnu.org/licenses/gpl-2.0.html and
-** https://www.gnu.org/licenses/gpl-3.0.html.
-**
-** $QT_END_LICENSE$
-**
-****************************************************************************/
+// Copyright (C) 2021 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
#include "qjniobject.h"
@@ -44,9 +8,15 @@
#include <QtCore/qbytearray.h>
#include <QtCore/qhash.h>
#include <QtCore/qreadwritelock.h>
+#include <QtCore/qloggingcategory.h>
+
QT_BEGIN_NAMESPACE
+Q_LOGGING_CATEGORY(lcJniThreadCheck, "qt.core.jni.threadcheck")
+
+using namespace Qt::StringLiterals;
+
/*!
\class QJniObject
\inmodule QtCore
@@ -54,7 +24,7 @@ QT_BEGIN_NAMESPACE
\brief A convenience wrapper around the Java Native Interface (JNI).
The QJniObject class wraps a reference to a Java object, ensuring it isn't
- gargage-collected and providing access to most \c JNIEnv method calls
+ garbage-collected and providing access to most \c JNIEnv method calls
(member, static) and fields (setter, getter). It eliminates much
boiler-plate that would normally be needed, with direct JNI access, for
every operation, including exception-handling.
@@ -74,55 +44,77 @@ QT_BEGIN_NAMESPACE
\section1 Method Signatures
- For functions that take no arguments, QJniObject provides convenience functions that will use
- the correct signature based on the provided template type. For example:
+ QJniObject provides convenience functions that will use the correct signature based on the
+ provided template types. For functions that only return and take \l {JNI types}, the
+ signature can be generate at compile time:
\code
jint x = QJniObject::callMethod<jint>("getSize");
QJniObject::callMethod<void>("touch");
+ jint ret = jString1.callMethod<jint>("compareToIgnoreCase", jString2.object<jstring>());
\endcode
- In other cases you will need to supply the signature yourself, and it is important that the
- signature matches the function you want to call. The signature structure is
- \c "(ArgumentsTypes)ReturnType". Array types in the signature must have the \c {[} prefix,
- and the fully-qualified \c Object type names must have the \c L prefix and the \c ; suffix.
+ These functions are variadic templates, and the compiler will deduce the template arguments
+ from the actual argument types. In many situations, only the return type needs to be provided
+ explicitly.
- The example below demonstrates how to call two different static functions:
+ For functions that take other argument types, you need to supply the signature yourself. It is
+ important that the signature matches the function you want to call. The example below
+ demonstrates how to call different static functions:
\code
// Java class
package org.qtproject.qt;
class TestClass
{
- static String fromNumber(int x) { ... }
- static String[] stringArray(String s1, String s2) { ... }
+ static TestClass create() { ... }
+ static String fromNumber(int x) { ... }
+ static String[] stringArray(String s1, String s2) { ... }
}
\endcode
- The signature for the first function is \c {"(I)Ljava/lang/String;"}:
+ The signature structure is \c "(ArgumentsTypes)ReturnType". Array types in the signature
+ must have the \c {[} prefix, and the fully-qualified \c Object type names must have the
+ \c L prefix and the \c ; suffix. The signature for the \c create function is
+ \c {"()Lorg/qtproject/qt/TestClass;}. The signatures for the second and third functions
+ are \c {"(I)Ljava/lang/String;"} and
+ \c {"(Ljava/lang/String;Ljava/lang/String;)[Ljava/lang/String;"}, respectively.
+
+ We can call the \c create() function like this:
+
+ \code
+ // C++ code
+ QJniObject testClass = QJniObject::callStaticObjectMethod("org/qtproject/qt/TestClass",
+ "create",
+ "()Lorg/qtproject/qt/TestClass;");
+ \endcode
+
+ For the second and third function we can rely on QJniObject's template methods to create
+ the implicit signature string, but we can also pass the signature string explicitly:
\code
// C++ code
QJniObject stringNumber = QJniObject::callStaticObjectMethod("org/qtproject/qt/TestClass",
- "fromNumber"
- "(I)Ljava/lang/String;",
- 10);
+ "fromNumber",
+ "(I)Ljava/lang/String;", 10);
\endcode
- and the signature for the second function is
- \c {"(Ljava/lang/String;Ljava/lang/String;)[Ljava/lang/String;"}:
+ For the implicit signature creation to work we need to specify the return type explicitly:
\code
// C++ code
QJniObject string1 = QJniObject::fromString("String1");
QJniObject string2 = QJniObject::fromString("String2");
- QJniObject stringArray = QJniObject::callStaticObjectMethod("org/qtproject/qt/TestClass",
+ QJniObject stringArray = QJniObject::callStaticObjectMethod<jstringArray>(
+ "org/qtproject/qt/TestClass",
"stringArray"
- "(Ljava/lang/String;Ljava/lang/String;)[Ljava/lang/String;"
string1.object<jstring>(),
string2.object<jstring>());
\endcode
+ Note that while the first template parameter specifies the return type of the Java
+ function, the method will still return a QJniObject.
+
\section1 Handling Java Exception
After calling Java functions that might throw exceptions, it is important
@@ -289,100 +281,151 @@ QT_BEGIN_NAMESPACE
class QJniObjectPrivate
{
public:
- QJniObjectPrivate() = default;
+ QJniObjectPrivate()
+ {
+ }
~QJniObjectPrivate() {
- QJniEnvironment env;
+ JNIEnv *env = QJniEnvironment::getJniEnv();
if (m_jobject)
env->DeleteGlobalRef(m_jobject);
if (m_jclass && m_own_jclass)
env->DeleteGlobalRef(m_jclass);
}
- friend jclass QtAndroidPrivate::findClass(const char *className, JNIEnv *env);
- static jclass loadClass(const QByteArray &className, JNIEnv *env, bool binEncoded = false)
- {
- return QJniObject::loadClass(className, env, binEncoded);
- }
-
- static QByteArray toBinaryEncClassName(const QByteArray &className)
+ template <typename ...Args>
+ void construct(const char *signature = nullptr, Args &&...args)
{
- return QJniObject::toBinaryEncClassName(className);
+ if (m_jclass) {
+ JNIEnv *env = QJniEnvironment::getJniEnv();
+ // get default constructor
+ jmethodID constructorId = QJniObject::getCachedMethodID(env, m_jclass, m_className, "<init>",
+ signature ? signature : "()V");
+ if (constructorId) {
+ jobject obj = nullptr;
+ if constexpr (sizeof...(Args) == 0)
+ obj = env->NewObject(m_jclass, constructorId);
+ else
+ obj = env->NewObjectV(m_jclass, constructorId, std::forward<Args>(args)...);
+ if (obj) {
+ m_jobject = env->NewGlobalRef(obj);
+ env->DeleteLocalRef(obj);
+ }
+ }
+ }
}
+ QByteArray m_className;
jobject m_jobject = nullptr;
jclass m_jclass = nullptr;
bool m_own_jclass = true;
- QByteArray m_className;
};
-static inline QLatin1String keyBase()
-{
- return QLatin1String("%1%2:%3");
-}
-
-static QString qt_convertJString(jstring string)
+template <typename ...Args>
+static inline QByteArray cacheKey(Args &&...args)
{
- QJniEnvironment env;
- int strLength = env->GetStringLength(string);
- QString res(strLength, Qt::Uninitialized);
- env->GetStringRegion(string, 0, strLength, reinterpret_cast<jchar *>(res.data()));
- return res;
+ return (QByteArrayView(":") + ... + QByteArrayView(args));
}
-typedef QHash<QString, jclass> JClassHash;
+typedef QHash<QByteArray, jclass> JClassHash;
Q_GLOBAL_STATIC(JClassHash, cachedClasses)
Q_GLOBAL_STATIC(QReadWriteLock, cachedClassesLock)
-static jclass getCachedClass(const QByteArray &classBinEnc, bool *isCached = nullptr)
+static jclass getCachedClass(const QByteArray &className)
{
QReadLocker locker(cachedClassesLock);
- const QHash<QString, jclass>::const_iterator &it = cachedClasses->constFind(QString::fromLatin1(classBinEnc));
- const bool found = (it != cachedClasses->constEnd());
-
- if (isCached)
- *isCached = found;
-
- return found ? it.value() : 0;
+ const auto &it = cachedClasses->constFind(className);
+ return it != cachedClasses->constEnd() ? it.value() : nullptr;
}
-QByteArray QJniObject::toBinaryEncClassName(const QByteArray &className)
+/*!
+ \internal
+
+ Get a JNI object from a jobject variant and do the necessary
+ exception clearing and delete the local reference before returning.
+ The JNI object can be null if there was an exception.
+*/
+static QJniObject getCleanJniObject(jobject object, JNIEnv *env)
{
- return QByteArray(className).replace('/', '.');
+ if (QJniEnvironment::checkAndClearExceptions(env) || !object) {
+ if (object)
+ env->DeleteLocalRef(object);
+ return QJniObject();
+ }
+
+ QJniObject res(object);
+ env->DeleteLocalRef(object);
+ return res;
}
-jclass QJniObject::loadClass(const QByteArray &className, JNIEnv *env, bool binEncoded)
+/*!
+ \internal
+ \a className must be slash-encoded
+*/
+jclass QtAndroidPrivate::findClass(const char *className, JNIEnv *env)
{
- const QByteArray &binEncClassName = binEncoded ? className : QJniObject::toBinaryEncClassName(className);
-
- bool isCached = false;
- jclass clazz = getCachedClass(binEncClassName, &isCached);
- if (clazz || isCached)
+ Q_ASSERT(env);
+ QByteArray classNameArray(className);
+#ifdef QT_DEBUG
+ if (classNameArray.contains('.')) {
+ qWarning("QtAndroidPrivate::findClass: className '%s' should use slash separators!",
+ className);
+ }
+#endif
+ classNameArray.replace('.', '/');
+ jclass clazz = getCachedClass(classNameArray);
+ if (clazz)
return clazz;
- QJniObject classLoader(QtAndroidPrivate::classLoader());
- if (!classLoader.isValid())
- return nullptr;
-
QWriteLocker locker(cachedClassesLock);
- // did we lose the race?
- const QLatin1String key(binEncClassName);
- const QHash<QString, jclass>::const_iterator &it = cachedClasses->constFind(key);
+ // Check again; another thread might have added the class to the cache after
+ // our call to getCachedClass and before we acquired the lock.
+ const auto &it = cachedClasses->constFind(classNameArray);
if (it != cachedClasses->constEnd())
return it.value();
- QJniObject stringName = QJniObject::fromString(key);
- QJniObject classObject = classLoader.callObjectMethod("loadClass",
- "(Ljava/lang/String;)Ljava/lang/Class;",
- stringName.object());
+ // JNIEnv::FindClass wants "a fully-qualified class name or an array type signature"
+ // which is a slash-separated class name.
+ jclass localClazz = env->FindClass(classNameArray.constData());
+ if (localClazz) {
+ clazz = static_cast<jclass>(env->NewGlobalRef(localClazz));
+ env->DeleteLocalRef(localClazz);
+ } else {
+ // Clear the exception silently; we are going to try the ClassLoader next,
+ // so no need for warning unless that fails as well.
+ env->ExceptionClear();
+ }
+
+ if (!clazz) {
+ // Wrong class loader, try our own
+ QJniObject classLoader(QtAndroidPrivate::classLoader());
+ if (!classLoader.isValid())
+ return nullptr;
+
+ // ClassLoader::loadClass on the other hand wants the binary name of the class,
+ // e.g. dot-separated. In testing it works also with /, but better to stick to
+ // the specification.
+ const QString binaryClassName = QString::fromLatin1(className).replace(u'/', u'.');
+ jstring classNameObject = env->NewString(reinterpret_cast<const jchar*>(binaryClassName.constData()),
+ binaryClassName.length());
+ QJniObject classObject = classLoader.callMethod<jclass>("loadClass", classNameObject);
+ env->DeleteLocalRef(classNameObject);
+
+ if (!QJniEnvironment::checkAndClearExceptions(env) && classObject.isValid())
+ clazz = static_cast<jclass>(env->NewGlobalRef(classObject.object()));
+ }
- if (!QJniEnvironment::checkAndClearExceptions(env) && classObject.isValid())
- clazz = static_cast<jclass>(env->NewGlobalRef(classObject.object()));
+ if (clazz)
+ cachedClasses->insert(classNameArray, clazz);
- cachedClasses->insert(key, clazz);
return clazz;
}
-typedef QHash<QString, jmethodID> JMethodIDHash;
+jclass QJniObject::loadClass(const QByteArray &className, JNIEnv *env)
+{
+ return QtAndroidPrivate::findClass(className, env);
+}
+
+typedef QHash<QByteArray, jmethodID> JMethodIDHash;
Q_GLOBAL_STATIC(JMethodIDHash, cachedMethodID)
Q_GLOBAL_STATIC(QReadWriteLock, cachedMethodIDLock)
@@ -401,9 +444,12 @@ jmethodID QJniObject::getMethodID(JNIEnv *env,
return id;
}
-void QJniObject::callVoidMethodV(JNIEnv *env, jmethodID id, va_list args) const
+void QJniObject::callVoidMethodV(JNIEnv *env, jmethodID id, ...) const
{
+ va_list args;
+ va_start(args, id);
env->CallVoidMethodV(d->m_jobject, id, args);
+ va_end(args);
}
jmethodID QJniObject::getCachedMethodID(JNIEnv *env,
@@ -416,10 +462,8 @@ jmethodID QJniObject::getCachedMethodID(JNIEnv *env,
if (className.isEmpty())
return getMethodID(env, clazz, name, signature, isStatic);
- const QString key = keyBase().arg(QLatin1String(className),
- QLatin1String(name),
- QLatin1String(signature));
- QHash<QString, jmethodID>::const_iterator it;
+ const QByteArray key = cacheKey(className, name, signature);
+ QHash<QByteArray, jmethodID>::const_iterator it;
{
QReadLocker locker(cachedMethodIDLock);
@@ -447,7 +491,7 @@ jmethodID QJniObject::getCachedMethodID(JNIEnv *env, const char *name,
return QJniObject::getCachedMethodID(env, d->m_jclass, d->m_className, name, signature, isStatic);
}
-typedef QHash<QString, jfieldID> JFieldIDHash;
+typedef QHash<QByteArray, jfieldID> JFieldIDHash;
Q_GLOBAL_STATIC(JFieldIDHash, cachedFieldID)
Q_GLOBAL_STATIC(QReadWriteLock, cachedFieldIDLock)
@@ -476,10 +520,8 @@ jfieldID QJniObject::getCachedFieldID(JNIEnv *env,
if (className.isNull())
return getFieldID(env, clazz, name, signature, isStatic);
- const QString key = keyBase().arg(QLatin1String(className),
- QLatin1String(name),
- QLatin1String(signature));
- QHash<QString, jfieldID>::const_iterator it;
+ const QByteArray key = cacheKey(className, name, signature);
+ QHash<QByteArray, jfieldID>::const_iterator it;
{
QReadLocker locker(cachedFieldIDLock);
@@ -509,39 +551,6 @@ jfieldID QJniObject::getCachedFieldID(JNIEnv *env,
return QJniObject::getCachedFieldID(env, d->m_jclass, d->m_className, name, signature, isStatic);
}
-jclass QtAndroidPrivate::findClass(const char *className, JNIEnv *env)
-{
- const QByteArray &classDotEnc = QJniObjectPrivate::toBinaryEncClassName(className);
- bool isCached = false;
- jclass clazz = getCachedClass(classDotEnc, &isCached);
-
- if (clazz || isCached)
- return clazz;
-
- const QLatin1String key(classDotEnc);
- if (env) { // We got an env. pointer (We expect this to be the right env. and call FindClass())
- QWriteLocker locker(cachedClassesLock);
- const QHash<QString, jclass>::const_iterator &it = cachedClasses->constFind(key);
- // Did we lose the race?
- if (it != cachedClasses->constEnd())
- return it.value();
-
- jclass fclazz = env->FindClass(className);
- if (!QJniEnvironment::checkAndClearExceptions(env)) {
- clazz = static_cast<jclass>(env->NewGlobalRef(fclazz));
- env->DeleteLocalRef(fclazz);
- }
-
- if (clazz)
- cachedClasses->insert(key, clazz);
- }
-
- if (!clazz) // We didn't get an env. pointer or we got one with the WRONG class loader...
- clazz = QJniObjectPrivate::loadClass(classDotEnc, QJniEnvironment().jniEnv(), true);
-
- return clazz;
-}
-
/*!
\fn QJniObject::QJniObject()
@@ -566,21 +575,11 @@ QJniObject::QJniObject()
QJniObject::QJniObject(const char *className)
: d(new QJniObjectPrivate())
{
- QJniEnvironment env;
- d->m_className = toBinaryEncClassName(className);
- d->m_jclass = loadClass(d->m_className, env.jniEnv(), true);
+ d->m_className = className;
+ d->m_jclass = loadClass(d->m_className, jniEnv());
d->m_own_jclass = false;
- if (d->m_jclass) {
- // get default constructor
- jmethodID constructorId = getCachedMethodID(env.jniEnv(), "<init>", "()V");
- if (constructorId) {
- jobject obj = env->NewObject(d->m_jclass, constructorId);
- if (obj) {
- d->m_jobject = env->NewGlobalRef(obj);
- env->DeleteLocalRef(obj);
- }
- }
- }
+
+ d->construct();
}
/*!
@@ -599,43 +598,31 @@ QJniObject::QJniObject(const char *className)
QJniObject::QJniObject(const char *className, const char *signature, ...)
: d(new QJniObjectPrivate())
{
- QJniEnvironment env;
- d->m_className = toBinaryEncClassName(className);
- d->m_jclass = loadClass(d->m_className, env.jniEnv(), true);
+ d->m_className = className;
+ d->m_jclass = loadClass(d->m_className, jniEnv());
d->m_own_jclass = false;
- if (d->m_jclass) {
- jmethodID constructorId = getCachedMethodID(env.jniEnv(), "<init>", signature);
- if (constructorId) {
- va_list args;
- va_start(args, signature);
- jobject obj = env->NewObjectV(d->m_jclass, constructorId, args);
- va_end(args);
- if (obj) {
- d->m_jobject = env->NewGlobalRef(obj);
- env->DeleteLocalRef(obj);
- }
- }
- }
+
+ va_list args;
+ va_start(args, signature);
+ d->construct(signature, args);
+ va_end(args);
}
-QJniObject::QJniObject(const char *className, const char *signature, const QVaListPrivate &args)
- : d(new QJniObjectPrivate())
-{
+/*!
+ \fn template<typename ...Args> QJniObject::QJniObject(const char *className, Args &&...args)
+ \since 6.4
+
+ Constructs a new JNI object by calling the constructor of \a className with
+ the arguments \a args. This constructor is only available if all \a args are
+ known \l {JNI Types}.
+
+ \code
QJniEnvironment env;
- d->m_className = toBinaryEncClassName(className);
- d->m_jclass = loadClass(d->m_className, env.jniEnv(), true);
- d->m_own_jclass = false;
- if (d->m_jclass) {
- jmethodID constructorId = getCachedMethodID(env.jniEnv(), "<init>", signature);
- if (constructorId) {
- jobject obj = env->NewObjectV(d->m_jclass, constructorId, args);
- if (obj) {
- d->m_jobject = env->NewGlobalRef(obj);
- env->DeleteLocalRef(obj);
- }
- }
- }
-}
+ char* str = "Hello";
+ jstring myJStringArg = env->NewStringUTF(str);
+ QJniObject myNewJavaString("java/lang/String", myJStringArg);
+ \endcode
+*/
/*!
Constructs a new JNI object from \a clazz by calling the constructor with
@@ -650,26 +637,31 @@ QJniObject::QJniObject(const char *className, const char *signature, const QVaLi
QJniObject::QJniObject(jclass clazz, const char *signature, ...)
: d(new QJniObjectPrivate())
{
- QJniEnvironment env;
if (clazz) {
- d->m_jclass = static_cast<jclass>(env->NewGlobalRef(clazz));
- if (d->m_jclass) {
- jmethodID constructorId = getMethodID(env.jniEnv(), d->m_jclass, "<init>", signature);
- if (constructorId) {
- va_list args;
- va_start(args, signature);
- jobject obj = env->NewObjectV(d->m_jclass, constructorId, args);
- va_end(args);
- if (obj) {
- d->m_jobject = env->NewGlobalRef(obj);
- env->DeleteLocalRef(obj);
- }
- }
- }
+ d->m_jclass = static_cast<jclass>(jniEnv()->NewGlobalRef(clazz));
+ va_list args;
+ va_start(args, signature);
+ d->construct(signature, args);
+ va_end(args);
}
}
/*!
+ \fn template<typename ...Args> QJniObject::QJniObject(jclass clazz, Args &&...args)
+ \since 6.4
+
+ Constructs a new JNI object from \a clazz by calling the constructor with
+ the arguments \a args. This constructor is only available if all \a args are
+ known \l {JNI Types}.
+
+ \code
+ QJniEnvironment env;
+ jclass myClazz = env.findClass("org/qtproject/qt/TestClass");
+ QJniObject(myClazz, 3);
+ \endcode
+*/
+
+/*!
Constructs a new JNI object by calling the default constructor of \a clazz.
\note The QJniObject will create a new reference to the class \a clazz
@@ -678,40 +670,8 @@ QJniObject::QJniObject(jclass clazz, const char *signature, ...)
*/
QJniObject::QJniObject(jclass clazz)
- : d(new QJniObjectPrivate())
+ : QJniObject(clazz, "()V")
{
- QJniEnvironment env;
- d->m_jclass = static_cast<jclass>(env->NewGlobalRef(clazz));
- if (d->m_jclass) {
- // get default constructor
- jmethodID constructorId = getMethodID(env.jniEnv(), d->m_jclass, "<init>", "()V");
- if (constructorId) {
- jobject obj = env->NewObject(d->m_jclass, constructorId);
- if (obj) {
- d->m_jobject = env->NewGlobalRef(obj);
- env->DeleteLocalRef(obj);
- }
- }
- }
-}
-
-QJniObject::QJniObject(jclass clazz, const char *signature, const QVaListPrivate &args)
- : d(new QJniObjectPrivate())
-{
- QJniEnvironment env;
- if (clazz) {
- d->m_jclass = static_cast<jclass>(env->NewGlobalRef(clazz));
- if (d->m_jclass) {
- jmethodID constructorId = getMethodID(env.jniEnv(), d->m_jclass, "<init>", signature);
- if (constructorId) {
- jobject obj = env->NewObjectV(d->m_jclass, constructorId, args);
- if (obj) {
- d->m_jobject = env->NewGlobalRef(obj);
- env->DeleteLocalRef(obj);
- }
- }
- }
- }
}
/*!
@@ -732,7 +692,7 @@ QJniObject::QJniObject(jobject object)
if (!object)
return;
- QJniEnvironment env;
+ JNIEnv *env = QJniEnvironment::getJniEnv();
d->m_jobject = env->NewGlobalRef(object);
jclass cls = env->GetObjectClass(object);
d->m_jclass = static_cast<jclass>(env->NewGlobalRef(cls));
@@ -740,25 +700,19 @@ QJniObject::QJniObject(jobject object)
}
/*!
- \brief Get a JNI object from a jobject variant and do the necessary
- exception clearing and delete the local reference before returning.
- The JNI object can be null if there was an exception.
-*/
-QJniObject QJniObject::getCleanJniObject(jobject object)
-{
- if (!object)
- return QJniObject();
+ \fn template<typename Class, typename ...Args> static inline QJniObject QJniObject::construct(Args &&...args)
+ \since 6.4
- QJniEnvironment env;
- if (env.checkAndClearExceptions()) {
- env->DeleteLocalRef(object);
- return QJniObject();
- }
+ Constructs an instance of the Java class that is the equivalent of \c Class and
+ returns a QJniObject containing the JNI object. The arguments in \a args are
+ passed to the Java constructor.
- QJniObject res(object);
- env->DeleteLocalRef(object);
- return res;
-}
+ \code
+ QJniObject javaString = QJniObject::construct<jstring>();
+ \endcode
+
+ This function is only available if all \a args are known \l {JNI Types}.
+*/
/*!
\fn QJniObject::~QJniObject()
@@ -768,7 +722,37 @@ QJniObject QJniObject::getCleanJniObject(jobject object)
QJniObject::~QJniObject()
{}
+namespace {
+QByteArray getClassNameHelper(JNIEnv *env, const QJniObjectPrivate *d)
+{
+ if (env->PushLocalFrame(3) != JNI_OK) // JVM out of memory
+ return QByteArray();
+
+ jmethodID mid = env->GetMethodID(d->m_jclass, "getClass", "()Ljava/lang/Class;");
+ jobject classObject = env->CallObjectMethod(d->m_jobject, mid);
+ jclass classObjectClass = env->GetObjectClass(classObject);
+ mid = env->GetMethodID(classObjectClass, "getName", "()Ljava/lang/String;");
+ jstring stringObject = static_cast<jstring>(env->CallObjectMethod(classObject, mid));
+ const jsize length = env->GetStringUTFLength(stringObject);
+ const char* nameString = env->GetStringUTFChars(stringObject, NULL);
+ const QByteArray result = QByteArray::fromRawData(nameString, length).replace('.', '/');
+ env->ReleaseStringUTFChars(stringObject, nameString);
+ env->PopLocalFrame(nullptr);
+ return result;
+}
+}
+
+/*! \internal
+
+ Returns the JNIEnv of the calling thread.
+*/
+JNIEnv *QJniObject::jniEnv() const noexcept
+{
+ return QJniEnvironment::getJniEnv();
+}
+
/*!
+ \fn jobject QJniObject::object() const
\fn template <typename T> T QJniObject::object() const
Returns the object held by the QJniObject either as jobject or as type T.
@@ -819,96 +803,51 @@ jclass QJniObject::objectClass() const
*/
QByteArray QJniObject::className() const
{
- return d->m_className;
-}
-
-QJniObject QJniObject::callObjectMethodV(const char *methodName,
- const char *signature,
- va_list args) const
-{
- QJniEnvironment env;
- jobject res = nullptr;
- jmethodID id = getCachedMethodID(env.jniEnv(), methodName, signature);
- if (id) {
- res = env->CallObjectMethodV(d->m_jobject, id, args);
- if (env.checkAndClearExceptions()) {
- env->DeleteLocalRef(res);
- res = nullptr;
- }
- }
-
- QJniObject obj(res);
- env->DeleteLocalRef(res);
- return obj;
-}
-
-QJniObject QJniObject::callStaticObjectMethodV(const char *className,
- const char *methodName,
- const char *signature,
- va_list args)
-{
- QJniEnvironment env;
- jobject res = nullptr;
- jclass clazz = loadClass(className, env.jniEnv());
- if (clazz) {
- jmethodID id = QJniObject::getCachedMethodID(env.jniEnv(), clazz, toBinaryEncClassName(className),
- methodName, signature, true);
- if (id) {
- res = env->CallStaticObjectMethodV(clazz, id, args);
- if (env.checkAndClearExceptions()) {
- env->DeleteLocalRef(res);
- res = nullptr;
- }
- }
+ if (d->m_className.isEmpty() && d->m_jclass && d->m_jobject) {
+ JNIEnv *env = jniEnv();
+ d->m_className = getClassNameHelper(env, d.get());
}
-
- QJniObject obj(res);
- env->DeleteLocalRef(res);
- return obj;
-}
-
-QJniObject QJniObject::callStaticObjectMethodV(jclass clazz,
- const char *methodName,
- const char *signature,
- va_list args)
-{
- QJniEnvironment env;
- jmethodID id = getMethodID(env.jniEnv(), clazz, methodName, signature, true);
- if (!id)
- return QJniObject();
-
- return getCleanJniObject(env->CallStaticObjectMethodV(clazz, id, args));
+ return d->m_className;
}
/*!
- \fn template <typename T> T QJniObject::callMethod(const char *methodName, const char *signature, ...) const
+ \fn template <typename Ret, typename ...Args> auto QJniObject::callMethod(const char *methodName, const char *signature, Args &&...args) const
+ \since 6.4
Calls the object's method \a methodName with \a signature specifying the types of any
- subsequent arguments.
+ subsequent arguments \a args, and returns the value (unless \c Ret is \c void). If \c Ret
+ is a jobject type, then the returned value will be a QJniObject.
\code
QJniObject myJavaStrin("org/qtproject/qt/TestClass");
jint index = myJavaString.callMethod<jint>("indexOf", "(I)I", 0x0051);
\endcode
-
*/
/*!
- \fn template <typename T> T QJniObject::callMethod(const char *methodName) const
+ \fn template <typename Ret, typename ...Args> auto QJniObject::callMethod(const char *methodName, Args &&...args) const
+ \since 6.4
- Calls the method \a methodName and returns the value.
+ Calls the method \a methodName with arguments \a args and returns the value
+ (unless \c Ret is \c void). If \c Ret is a jobject type, then the returned value
+ will be a QJniObject.
\code
QJniObject myJavaStrin("org/qtproject/qt/TestClass");
jint size = myJavaString.callMethod<jint>("length");
\endcode
+
+ The method signature is deduced at compile time from \c Ret and the types of \a args.
*/
/*!
- \fn template <typename T> T QJniObject::callStaticMethod(const char *className, const char *methodName, const char *signature, ...)
+ \fn template <typename Ret, typename ...Args> auto QJniObject::callStaticMethod(const char *className, const char *methodName, const char *signature, Args &&...args)
+ \since 6.4
Calls the static method \a methodName from class \a className with \a signature
- specifying the types of any subsequent arguments.
+ specifying the types of any subsequent arguments \a args. Returns the result of
+ the method (unless \c Ret is \c void). If \c Ret is a jobject type, then the
+ returned value will be a QJniObject.
\code
jint a = 2;
@@ -918,20 +857,27 @@ QJniObject QJniObject::callStaticObjectMethodV(jclass clazz,
*/
/*!
- \fn template <typename T> T QJniObject::callStaticMethod(const char *className, const char *methodName)
+ \fn template <typename Ret, typename ...Args> auto QJniObject::callStaticMethod(const char *className, const char *methodName, Args &&...args)
+ \since 6.4
- Calls the static method \a methodName on class \a className and returns the value.
+ Calls the static method \a methodName on class \a className with arguments \a args,
+ and returns the value of type \c Ret (unless \c Ret is \c void). If \c Ret
+ is a jobject type, then the returned value will be a QJniObject.
\code
jint value = QJniObject::callStaticMethod<jint>("MyClass", "staticMethod");
\endcode
+
+ The method signature is deduced at compile time from \c Ret and the types of \a args.
*/
/*!
- \fn template <typename T> T QJniObject::callStaticMethod(jclass clazz, const char *methodName, const char *signature, ...)
+ \fn template <typename Ret, typename ...Args> auto QJniObject::callStaticMethod(jclass clazz, const char *methodName, const char *signature, Args &&...args)
Calls the static method \a methodName from \a clazz with \a signature
- specifying the types of any subsequent arguments.
+ specifying the types of any subsequent arguments. Returns the result of
+ the method (unless \c Ret is \c void). If \c Ret is a jobject type, then the
+ returned value will be a QJniObject.
\code
QJniEnvironment env;
@@ -943,11 +889,15 @@ QJniObject QJniObject::callStaticObjectMethodV(jclass clazz,
*/
/*!
- \fn template <typename T> T QJniObject::callStaticMethod(jclass clazz, jmethodID methodId, ...)
+ \fn template <typename Ret, typename ...Args> auto QJniObject::callStaticMethod(jclass clazz, jmethodID methodId, Args &&...args)
+ \since 6.4
Calls the static method identified by \a methodId from the class \a clazz
- with any subsequent arguments. Useful when \a clazz and \a methodId are
- already cached from previous operations.
+ with any subsequent arguments, and returns the value of type \c Ret (unless
+ \c Ret is \c void). If \c Ret is a jobject type, then the returned value will
+ be a QJniObject.
+
+ Useful when \a clazz and \a methodId are already cached from previous operations.
\code
QJniEnvironment env;
@@ -962,15 +912,32 @@ QJniObject QJniObject::callStaticObjectMethodV(jclass clazz,
*/
/*!
- \fn template <typename T> T QJniObject::callStaticMethod(jclass clazz, const char *methodName)
+ \fn template <typename Ret, typename ...Args> auto QJniObject::callStaticMethod(jclass clazz, const char *methodName, Args &&...args)
+ \since 6.4
- Calls the static method \a methodName on \a clazz and returns the value.
+ Calls the static method \a methodName on \a clazz and returns the value of type \c Ret
+ (unless \c Ret is \c void). If \c Ret is a jobject type, then the returned value will
+ be a QJniObject.
\code
QJniEnvironment env;
jclass javaMathClass = env.findClass("java/lang/Math");
jdouble randNr = QJniObject::callStaticMethod<jdouble>(javaMathClass, "random");
\endcode
+
+ The method signature is deduced at compile time from \c Ret and the types of \a args.
+*/
+
+/*!
+ \fn template <typename Klass, typename Ret, typename ...Args> auto QJniObject::callStaticMethod(const char *methodName, Args &&...args)
+ \since 6.7
+
+ Calls the static method \a methodName on the class \c Klass and returns the value of type
+ \c Ret (unless \c Ret is \c void). If \c Ret is a jobject type, then the returned value will
+ be a QJniObject.
+
+ The method signature is deduced at compile time from \c Ret and the types of \a args.
+ \c Klass needs to be a C++ type with a registered type mapping to a Java type.
*/
/*!
@@ -987,12 +954,11 @@ QJniObject QJniObject::callStaticObjectMethodV(jclass clazz,
*/
QJniObject QJniObject::callObjectMethod(const char *methodName, const char *signature, ...) const
{
- QJniEnvironment env;
- jmethodID id = getCachedMethodID(env.jniEnv(), methodName, signature);
+ jmethodID id = getCachedMethodID(jniEnv(), methodName, signature);
if (id) {
va_list args;
va_start(args, signature);
- QJniObject res = getCleanJniObject(env->CallObjectMethodV(d->m_jobject, id, args));
+ QJniObject res = getCleanJniObject(jniEnv()->CallObjectMethodV(d->m_jobject, id, args), jniEnv());
va_end(args);
return res;
}
@@ -1016,16 +982,16 @@ QJniObject QJniObject::callObjectMethod(const char *methodName, const char *sign
QJniObject QJniObject::callStaticObjectMethod(const char *className, const char *methodName,
const char *signature, ...)
{
- QJniEnvironment env;
- jclass clazz = QJniObject::loadClass(className, env.jniEnv());
+ JNIEnv *env = QJniEnvironment::getJniEnv();
+ jclass clazz = QJniObject::loadClass(className, env);
if (clazz) {
- jmethodID id = QJniObject::getCachedMethodID(env.jniEnv(), clazz,
- QJniObject::toBinaryEncClassName(className),
+ jmethodID id = QJniObject::getCachedMethodID(env, clazz,
+ className,
methodName, signature, true);
if (id) {
va_list args;
va_start(args, signature);
- QJniObject res = getCleanJniObject(env->CallStaticObjectMethodV(clazz, id, args));
+ QJniObject res = getCleanJniObject(env->CallStaticObjectMethodV(clazz, id, args), env);
va_end(args);
return res;
}
@@ -1043,13 +1009,13 @@ QJniObject QJniObject::callStaticObjectMethod(const char *className, const char
QJniObject QJniObject::callStaticObjectMethod(jclass clazz, const char *methodName,
const char *signature, ...)
{
- QJniEnvironment env;
if (clazz) {
+ QJniEnvironment env;
jmethodID id = getMethodID(env.jniEnv(), clazz, methodName, signature, true);
if (id) {
va_list args;
va_start(args, signature);
- QJniObject res = getCleanJniObject(env->CallStaticObjectMethodV(clazz, id, args));
+ QJniObject res = getCleanJniObject(env->CallStaticObjectMethodV(clazz, id, args), env.jniEnv());
va_end(args);
return res;
}
@@ -1075,11 +1041,11 @@ QJniObject QJniObject::callStaticObjectMethod(jclass clazz, const char *methodNa
*/
QJniObject QJniObject::callStaticObjectMethod(jclass clazz, jmethodID methodId, ...)
{
- QJniEnvironment env;
if (clazz && methodId) {
+ QJniEnvironment env;
va_list args;
va_start(args, methodId);
- QJniObject res = getCleanJniObject(env->CallStaticObjectMethodV(clazz, methodId, args));
+ QJniObject res = getCleanJniObject(env->CallStaticObjectMethodV(clazz, methodId, args), env.jniEnv());
va_end(args);
return res;
}
@@ -1088,36 +1054,44 @@ QJniObject QJniObject::callStaticObjectMethod(jclass clazz, jmethodID methodId,
}
/*!
- \fn QJniObject QJniObject::callObjectMethod(const char *methodName) const
+ \fn template<typename Ret, typename ...Args> QJniObject QJniObject::callObjectMethod(const char *methodName, Args &&...args) const
+ \since 6.4
- Calls the Java objects method \a methodName and returns a new QJniObject for
- the returned Java object.
+ Calls the Java objects method \a methodName with arguments \a args and returns a
+ new QJniObject for the returned Java object.
\code
QJniObject myJavaString = QJniObject::fromString("Hello, Java");
QJniObject myJavaString2 = myJavaString1.callObjectMethod<jstring>("toString");
\endcode
+
+ The method signature is deduced at compile time from \c Ret and the types of \a args.
*/
/*!
- \fn QJniObject QJniObject::callStaticObjectMethod(const char *className, const char *methodName)
+ \fn template<typename Ret, typename ...Args> QJniObject QJniObject::callStaticObjectMethod(const char *className, const char *methodName, Args &&...args)
+ \since 6.4
- Calls the static method with \a methodName on the class \a className.
+ Calls the static method with \a methodName on the class \a className, passing
+ arguments \a args, and returns a new QJniObject for the returned Java object.
\code
QJniObject string = QJniObject::callStaticObjectMethod<jstring>("CustomClass", "getClassName");
\endcode
+
+ The method signature is deduced at compile time from \c Ret and the types of \a args.
*/
/*!
- \fn QJniObject QJniObject::callStaticObjectMethod(jclass clazz, const char *methodName)
-
- Calls the static method with \a methodName on \a clazz.
+ \fn template<typename Ret, typename ...Args> QJniObject QJniObject::callStaticObjectMethod(jclass clazz, const char *methodName, Args &&...args)
+ \since 6.4
+ Calls the static method with \a methodName on \a clazz, passing arguments \a args,
+ and returns a new QJniObject for the returned Java object.
*/
/*!
- \fn template <typename T> QJniObject &QJniObject::operator=(T object)
+ \fn template <typename T, std::enable_if_t<std::is_convertible_v<T, jobject>, bool> = true> QJniObject &QJniObject::operator=(T object)
Replace the current object with \a object. The old Java object will be released.
*/
@@ -1138,7 +1112,7 @@ QJniObject QJniObject::callStaticObjectMethod(jclass clazz, jmethodID methodId,
*/
/*!
- \fn T QJniObject::getField(const char *fieldName) const
+ \fn template<typename T> T QJniObject::getField(const char *fieldName) const
Retrieves the value of the field \a fieldName.
@@ -1149,18 +1123,26 @@ QJniObject QJniObject::callStaticObjectMethod(jclass clazz, jmethodID methodId,
*/
/*!
- \fn T QJniObject::getStaticField(const char *className, const char *fieldName)
+ \fn template<typename T> T QJniObject::getStaticField(const char *className, const char *fieldName)
Retrieves the value from the static field \a fieldName on the class \a className.
*/
/*!
- \fn T QJniObject::getStaticField(jclass clazz, const char *fieldName)
+ \fn template<typename T> T QJniObject::getStaticField(jclass clazz, const char *fieldName)
Retrieves the value from the static field \a fieldName on \a clazz.
*/
/*!
+ \fn template <typename Klass, typename T> auto QJniObject::getStaticField(const char *fieldName)
+
+ Retrieves the value from the static field \a fieldName for the class \c Klass.
+
+ \c Klass needs to be a C++ type with a registered type mapping to a Java type.
+*/
+
+/*!
\fn template <typename T> void QJniObject::setStaticField(const char *className, const char *fieldName, T value)
Sets the static field \a fieldName of the class \a className to \a value.
@@ -1173,6 +1155,14 @@ QJniObject QJniObject::callStaticObjectMethod(jclass clazz, jmethodID methodId,
*/
/*!
+ \fn template <typename Klass, typename T> auto QJniObject::setStaticField(const char *fieldName, T value)
+
+ Sets the static field \a fieldName of the class \c Klass to \a value.
+
+ \c Klass needs to be a C++ type with a registered type mapping to a Java type.
+*/
+
+/*!
\fn QJniObject QJniObject::getStaticObjectField(const char *className, const char *fieldName, const char *signature)
Retrieves a JNI object from the field \a fieldName with \a signature from
@@ -1189,18 +1179,18 @@ QJniObject QJniObject::getStaticObjectField(const char *className,
const char *fieldName,
const char *signature)
{
- QJniEnvironment env;
- jclass clazz = QJniObject::loadClass(className, env.jniEnv());
+ JNIEnv *env = QJniEnvironment::getJniEnv();
+ jclass clazz = QJniObject::loadClass(className, env);
if (!clazz)
return QJniObject();
- jfieldID id = QJniObject::getCachedFieldID(env.jniEnv(), clazz,
- QJniObject::toBinaryEncClassName(className),
+ jfieldID id = QJniObject::getCachedFieldID(env, clazz,
+ className,
fieldName,
signature, true);
if (!id)
return QJniObject();
- return getCleanJniObject(env->GetStaticObjectField(clazz, id));
+ return getCleanJniObject(env->GetStaticObjectField(clazz, id), env);
}
/*!
@@ -1218,12 +1208,9 @@ QJniObject QJniObject::getStaticObjectField(const char *className,
QJniObject QJniObject::getStaticObjectField(jclass clazz, const char *fieldName,
const char *signature)
{
- QJniEnvironment env;
- jfieldID id = getFieldID(env.jniEnv(), clazz, fieldName, signature, true);
- if (!id)
- return QJniObject();
-
- return getCleanJniObject(env->GetStaticObjectField(clazz, id));
+ JNIEnv *env = QJniEnvironment::getJniEnv();
+ jfieldID id = getFieldID(env, clazz, fieldName, signature, true);
+ return getCleanJniObject(env->GetStaticObjectField(clazz, id), env);
}
/*!
@@ -1240,7 +1227,7 @@ QJniObject QJniObject::getStaticObjectField(jclass clazz, const char *fieldName,
*/
/*!
- \fn QJniObject QJniObject::getObjectField(const char *fieldName) const
+ \fn template<typename T> QJniObject QJniObject::getObjectField(const char *fieldName) const
Retrieves a JNI object from the field \a fieldName.
@@ -1262,12 +1249,11 @@ QJniObject QJniObject::getStaticObjectField(jclass clazz, const char *fieldName,
*/
QJniObject QJniObject::getObjectField(const char *fieldName, const char *signature) const
{
- QJniEnvironment env;
- jfieldID id = getCachedFieldID(env.jniEnv(), fieldName, signature);
+ jfieldID id = getCachedFieldID(jniEnv(), fieldName, signature);
if (!id)
return QJniObject();
- return getCleanJniObject(env->GetObjectField(d->m_jobject, id));
+ return getCleanJniObject(jniEnv()->GetObjectField(d->m_jobject, id), jniEnv());
}
/*!
@@ -1284,7 +1270,7 @@ QJniObject QJniObject::getObjectField(const char *fieldName, const char *signatu
*/
/*!
- \fn QJniObject QJniObject::getStaticObjectField(const char *className, const char *fieldName)
+ \fn template<typename T> QJniObject QJniObject::getStaticObjectField(const char *className, const char *fieldName)
Retrieves the object from the field \a fieldName on the class \a className.
@@ -1294,7 +1280,7 @@ QJniObject QJniObject::getObjectField(const char *fieldName, const char *signatu
*/
/*!
- \fn QJniObject QJniObject::getStaticObjectField(jclass clazz, const char *fieldName)
+ \fn template<typename T> QJniObject QJniObject::getStaticObjectField(jclass clazz, const char *fieldName)
Retrieves the object from the field \a fieldName on \a clazz.
@@ -1318,8 +1304,11 @@ QJniObject QJniObject::getObjectField(const char *fieldName, const char *signatu
QJniObject QJniObject::fromString(const QString &string)
{
QJniEnvironment env;
- return getCleanJniObject(env->NewString(reinterpret_cast<const jchar*>(string.constData()),
- string.length()));
+ jstring stringRef = env->NewString(reinterpret_cast<const jchar*>(string.constData()),
+ string.length());
+ QJniObject stringObject = getCleanJniObject(stringRef, env.jniEnv());
+ stringObject.d->m_className = "java/lang/String";
+ return stringObject;
}
/*!
@@ -1342,7 +1331,10 @@ QString QJniObject::toString() const
return QString();
QJniObject string = callObjectMethod<jstring>("toString");
- return qt_convertJString(static_cast<jstring>(string.object()));
+ const int strLength = string.jniEnv()->GetStringLength(string.object<jstring>());
+ QString res(strLength, Qt::Uninitialized);
+ string.jniEnv()->GetStringRegion(string.object<jstring>(), 0, strLength, reinterpret_cast<jchar *>(res.data()));
+ return res;
}
/*!
@@ -1363,7 +1355,7 @@ bool QJniObject::isClassAvailable(const char *className)
if (!env.jniEnv())
return false;
- return loadClass(className, env.jniEnv());;
+ return loadClass(className, env.jniEnv());
}
/*!
@@ -1399,13 +1391,17 @@ bool QJniObject::isValid() const
QJniObject QJniObject::fromLocalRef(jobject lref)
{
QJniObject obj(lref);
- QJniEnvironment()->DeleteLocalRef(lref);
+ obj.jniEnv()->DeleteLocalRef(lref);
return obj;
}
bool QJniObject::isSameObject(jobject obj) const
{
- return QJniEnvironment()->IsSameObject(d->m_jobject, obj);
+ if (d->m_jobject == obj)
+ return true;
+ if (!d->m_jobject || !obj)
+ return false;
+ return jniEnv()->IsSameObject(d->m_jobject, obj);
}
bool QJniObject::isSameObject(const QJniObject &other) const
@@ -1415,15 +1411,14 @@ bool QJniObject::isSameObject(const QJniObject &other) const
void QJniObject::assign(jobject obj)
{
- if (isSameObject(obj))
+ if (d && isSameObject(obj))
return;
- jobject jobj = static_cast<jobject>(obj);
d = QSharedPointer<QJniObjectPrivate>::create();
if (obj) {
- QJniEnvironment env;
- d->m_jobject = env->NewGlobalRef(jobj);
- jclass objectClass = env->GetObjectClass(jobj);
+ JNIEnv *env = QJniEnvironment::getJniEnv();
+ d->m_jobject = env->NewGlobalRef(obj);
+ jclass objectClass = env->GetObjectClass(obj);
d->m_jclass = static_cast<jclass>(env->NewGlobalRef(objectClass));
env->DeleteLocalRef(objectClass);
}