{"id":135,"date":"2007-04-12T00:38:00","date_gmt":"2007-04-12T00:38:00","guid":{"rendered":"https:\/\/zofxare.com\/zofxare\/blog\/2007\/04\/12\/c-java-native-interface-jni\/"},"modified":"2007-04-12T00:38:00","modified_gmt":"2007-04-12T00:38:00","slug":"c-java-native-interface-jni","status":"publish","type":"post","link":"https:\/\/zofxare.com\/zofxare\/blog\/2007\/04\/12\/c-java-native-interface-jni\/","title":{"rendered":"C++, Java Native Interface (JNI)"},"content":{"rendered":"

In my recent Java Native Interface (JNI) adventures, I have discovered that when calling the JNI function NewObject in C++, you need to cast the variables to their corresponding jni type. I didn’t have to do this when using C and jni.
Example:
C++ struct ABC { double x, double y };<\/p>\n

Using C++ create a jni object to pass to java:<\/p>\n

jobject createABC( JNIEnv* env, jobject obj )
{
ABC abc;
a.x = 5.2;
a.y = 2.4;<\/p>\n

jclass cls = env->FindClass( “ABC” ); \/\/ find the java ABC class<\/p>\n

jmethodID mid = env->GetMethodID( cls, ““, “(DD)V” );<\/p>\n

jobject jabc = env->NewObject( cls, mid, (jdouble)a.x, (jdouble)a.y);<\/p>\n

return jabc;
}<\/p>\n

\"Error“id=”BLOGGER_PHOTO_ID_5052354926391138034” \/><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

In my recent Java Native Interface (JNI) adventures, I have discovered that when calling the JNI function NewObject in C++, you need to cast the variables to their corresponding jni type. I didn’t have to do this when using C and jni.Example:C++ struct ABC { double x, double y }; Using C++ create a jni […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"nf_dc_page":"","om_disable_all_campaigns":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[288,289,287],"tags":[],"class_list":["post-135","post","type-post","status-publish","format-standard","hentry","category-c","category-casting","category-java-native-interface-jni"],"yoast_head":"\nC++, Java Native Interface (JNI) - Zofxare Blog Home<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/zofxare.com\/zofxare\/blog\/2007\/04\/12\/c-java-native-interface-jni\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"C++, Java Native Interface (JNI) - Zofxare Blog Home\" \/>\n<meta property=\"og:description\" content=\"In my recent Java Native Interface (JNI) adventures, I have discovered that when calling the JNI function NewObject in C++, you need to cast the variables to their corresponding jni type. I didn’t have to do this when using C and jni.Example:C++ struct ABC { double x, double y }; Using C++ create a jni […]\" \/>\n<meta property=\"og:url\" content=\"https:\/\/zofxare.com\/zofxare\/blog\/2007\/04\/12\/c-java-native-interface-jni\/\" \/>\n<meta property=\"og:site_name\" content=\"Zofxare Blog Home\" \/>\n<meta property=\"article:published_time\" content=\"2007-04-12T00:38:00+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/blogger.googleusercontent.com\/img\/b\/R29vZ2xl\/AVvXsEhDSyEuZ7KeKa9w1bvLrZ392F1fVjJPO5UEd55XOtgnZxXUmUu-i3aIx28iagSyKCgYodEsllZgD570-uSo1heK6K94fEKwzPV-US0NqetCAJ-UYq6WeM8x9o7RpUts3eXG6tPr5OIpofS8\/s400\/error_doctor.gif\" \/>\n<meta name=\"author\" content=\"zofxare\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"zofxare\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"1 minute\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/zofxare.com\\\/zofxare\\\/blog\\\/2007\\\/04\\\/12\\\/c-java-native-interface-jni\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/zofxare.com\\\/zofxare\\\/blog\\\/2007\\\/04\\\/12\\\/c-java-native-interface-jni\\\/\"},\"author\":{\"name\":\"zofxare\",\"@id\":\"https:\\\/\\\/zofxare.com\\\/zofxare\\\/blog\\\/#\\\/schema\\\/person\\\/094f5dde70100b9f8fbc63174a2a40ce\"},\"headline\":\"C++, Java Native Interface (JNI)\",\"datePublished\":\"2007-04-12T00:38:00+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/zofxare.com\\\/zofxare\\\/blog\\\/2007\\\/04\\\/12\\\/c-java-native-interface-jni\\\/\"},\"wordCount\":109,\"commentCount\":0,\"image\":{\"@id\":\"https:\\\/\\\/zofxare.com\\\/zofxare\\\/blog\\\/2007\\\/04\\\/12\\\/c-java-native-interface-jni\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/blogger.googleusercontent.com\\\/img\\\/b\\\/R29vZ2xl\\\/AVvXsEhDSyEuZ7KeKa9w1bvLrZ392F1fVjJPO5UEd55XOtgnZxXUmUu-i3aIx28iagSyKCgYodEsllZgD570-uSo1heK6K94fEKwzPV-US0NqetCAJ-UYq6WeM8x9o7RpUts3eXG6tPr5OIpofS8\\\/s400\\\/error_doctor.gif\",\"articleSection\":[\"C++\",\"casting\",\"Java Native Interface (JNI)\"],\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"CommentAction\",\"name\":\"Comment\",\"target\":[\"https:\\\/\\\/zofxare.com\\\/zofxare\\\/blog\\\/2007\\\/04\\\/12\\\/c-java-native-interface-jni\\\/#respond\"]}]},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/zofxare.com\\\/zofxare\\\/blog\\\/2007\\\/04\\\/12\\\/c-java-native-interface-jni\\\/\",\"url\":\"https:\\\/\\\/zofxare.com\\\/zofxare\\\/blog\\\/2007\\\/04\\\/12\\\/c-java-native-interface-jni\\\/\",\"name\":\"C++, Java Native Interface (JNI) - 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