实现文件
// // Created by Peng Cai on 2018/10/16. //
# include "include/call_super.h"
# include
# include
# include
JNIEXPORT void JNICALL Java_org_professor_jni_MainActivity_callNativeSuperInstanceMethod(JNIEnv *env, jobject instance) {
//1. 获取类类型
jclass birdClazz = (*env)->FindClass(env, "org/professor/jni/animal/Bird");
if (NULL == birdClazz) {
__android_log_print(ANDROID_LOG_WARN, "ANIMAL", "Create Bird Class Failed");
return;
}
//2.获取构造函数ID 构造方法的名统一为:<init>
jmethodID birdInstanceMethodId = (*env)->GetMethodID(env, birdClazz, "<init>",
"(Ljava/long/String;)V");
if (NULL == birdInstanceMethodId) {
__android_log_print(ANDROID_LOG_WARN, "ANIMAL", "Create Bird Instance Method Id Failed");
return;
}
//3. 创建一个对象实例
jstring name = (*env)->NewStringUTF(env, "YIMI");
if (NULL == name) {
//有可能内存不够
__android_log_print(ANDROID_LOG_WARN, "ANIMAL", "Create Bird Name Failed");
return;
}
jobject birdObj = (*env)->NewObject(env, birdClazz, birdInstanceMethodId, name);
if (NULL == birdObj) {
__android_log_print(ANDROID_LOG_WARN, "ANIMAL", "Create Bird Instance Obj Failed");
return;
}
// 4.获取调用方法ID
jmethodID birdGetNameMethodID = (*env)->GetMethodID(env, birdClazz, "getName",
"()Ljava/long/String;");
if (NULL == birdGetNameMethodID) {
__android_log_print(ANDROID_LOG_WARN, "ANIMAL", "Create Bird Get Name Method Id Failed");
return;
}
//5. 调用自己getName方法
jstring birdName = (*env)->CallObjectMethod(env, birdObj, birdGetNameMethodID);
if (NULL != birdName) {
const char *c_bird_name = (*env)->GetStringUTFChars(env, birdName,
JNI_FALSE); //转换编码格式 在C里面用 JNI_FALSE代表不拷贝到缓冲区
if (NULL != c_bird_name) {
__android_log_print(ANDROID_LOG_WARN, "ANIMAL bird name = %s", c_bird_name);
//释放从java层获取到的字符串所分配的内存
(*env)->ReleaseStringUTFChars(env, birdName, c_bird_name);
}
}
//-------华丽分割线--------------
//6. 获取父类的Clazz
jclass animalClazz = (*env)->FindClass(env, "org/professor/jni/Animal");
if (NULL == animalClazz) {
__android_log_print(ANDROID_LOG_WARN, "ANIMAL", "Create Animal Class Failed");
return;
}
//7.获取父类方法ID eat方法
jmethodID animalEatMethodID = (*env)->GetMethodID(env, animalClazz, "eat", "()V");
if (NULL == animalEatMethodID) {
__android_log_print(ANDROID_LOG_WARN, "ANIMAL", "Create Animal Eat Method Id Failed");
return;
}
//8.子类调用父类方法 eat
//注意:birdObj是Bird的实例,animalClazz是Animal的Class引用,animalEatMethodID是Animal类中的方法ID
(*env)->CallNonvirtualVoidMethod(env, birdObj, animalClazz, animalEatMethodID);
//--------------华丽分割线------------------
// 9.获取父类调用方法getName
jmethodID animalGetNameMethodID = (*env)->GetMethodID(env, animalClazz, "getName",
"()Ljava/long/String;");
if (NULL == animalGetNameMethodID) {
__android_log_print(ANDROID_LOG_WARN, "ANIMAL", "Create Animal Get Name Method Id Failed");
return;
}
//10.子类调用父类GetName 方法
jstring animalName = (*env)->CallNonvirtualObjectMethod(env, birdObj, animalClazz,
animalGetNameMethodID);
if (NULL != animalName) {
const char *c_animal_name = (*env)->GetStringUTFChars(env, animalName, JNI_FALSE);
if (NULL != c_animal_name) {
__android_log_print(ANDROID_LOG_WARN, "ANIMAL animal name = %s",
c_animal_name);
//释放从java层获取到的字符串所分配的内存
(*env)->ReleaseStringUTFChars(env, animalName, c_animal_name);
}
}
quit:
// 删除局部引用变量 jmethod 不是引用类型 (jobject或jobject的子类才属于引用变量)
(*env)->DeleteLocalRef(env, birdClazz);
(*env)->DeleteLocalRef(env, animalClazz);
(*env)->DeleteLocalRef(env, name);
(*env)->DeleteLocalRef(env, birdObj);
(*env)->DeleteLocalRef(env, birdName);
(*env)->DeleteLocalRef(env, animalName);
} ```