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@cawka
Created July 4, 2019 23:51
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In native code, create the following:
// Globals
static jmethodID midStr;
static char * sigStr = "(Ljava/lang/String;ILjava/lang/String;)V";
// Init - One time to initialize the method id, (use an init() function)
midStr = (*env)->GetMethodID(env, class, "javaDefineString", sigStr);
// Methods
static void javaDefineString(JNIEnv * env, jobject o, char * name, jint index, char * value) {
jstring string = (*env)->NewStringUTF(env, name);
(*env)->CallVoidMethod(env, o, midStr, string, index, (*env)->NewStringUTF(env, value));
}
In Java code create the following:
Map<String, String> strings = new HashMap<String, String>();
// Never call this from Java
void javaDefineString(String name, int index, String value) {
String key = name + "." + index;
strings.put(key, value);
}
Native usage to send data:
javaDefineString(env, o, "Greet", 0, "Hello from native code");
javaDefineString(env, o, "KeyTimeout", 0, "one second");
javaDefineString(env, o, "KeyTimeout", 1, "two second");
Java usage to receive data:
System.out.println(strings.get("Greet.0");
System.out.println(strings.get("KeyTimeout.0");
System.out.println(strings.get("KeyTimeout.1");
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