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copied!<p>You can use <a href="http://en.cppreference.com/w/cpp/memory/unique_ptr" rel="noreferrer"><code>std::unique_ptr</code></a> in C++11, which allows you to set the deleter yourself:</p> <pre><code>#include <memory> #include <functional> typedef std::unique_ptr<char const[], std::function<void(char const*)>> jni_string_ptr; // the "std::function" is needed to store any callable† extern "C" JNIEXPORT void JNICALL Java_ClassName_MethodName (JNIEnv *env, jobject obj, jstring javaString) { //Get the native string from javaString jni_string_ptr nativeString(env->GetStringUTFChars(javaString, 0), [=](char const* p) mutable{ env->ReleaseStringUTFChars(javaString, p); }); // lambda as the deleter // mutable needed if "ReleaseStringUTFChars" is a non-const method //Do something with the nativeString // nativeString automatically calls the passed deleter } </code></pre> <p>If you're stuck in C++03 and don't have access to <code>std::unique_ptr</code>, <a href="http://www.boost.org/libs/smart_ptr/shared_ptr.htm" rel="noreferrer"><code>boost::shared_array</code></a> provides a.. <em>viable</em> alternative.</p> <pre><code>#include <boost/shared_ptr.hpp> typedef boost::shared_array<char const*> jni_string_ptr; struct jni_string_deleter{ jni_string_deleter(JNIEnv* e, jstring js) : _env(e), _java_string(js) {} void operator()(char const* p) const{ _env->ReleaseStringUTFChars(_java_string, p); } private: JNIEnv* _env; jstring _java_string; }; extern "C" JNIEXPORT void JNICALL Java_ClassName_MethodName (JNIEnv *env, jobject obj, jstring javaString) { //Get the native string from javaString jni_string_ptr nativeString(env->GetStringUTFChars(javaString, 0), jni_string_deleter(env, javaString)); //Do something with the nativeString // nativeString automatically calls the passed deleter } </code></pre> <hr> <p>† You can also use a specific delter type here, as with the <code>shared_array</code> example, to avoid the type-erasure overhead of <code>std::function</code>:</p> <pre><code>struct jni_string_deleter{ jni_string_deleter(JNIEnv* e, jstring js) : _env(e), _java_string(js) {} void operator()(char const* p) const{ _env->ReleaseStringUTFChars(_java_string, p); } private: JNIEnv* _env; jstring _java_string; }; typedef std::unique_ptr<char const[], jni_string_deleter> jni_string_ptr; // create jni_string_ptr(env->get_the_chars(), jni_string_deleter(env, javaString)); </code></pre>

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