Get Strings used in Java from JNI
JAVA Code
Here is some part of my code that I have written in JAVA, As you can see this is a class called JC_VerificationCandidate
that have two String
members enrollmentID
and seedIndex
.
class JC_VerificationCandidate {
public JCDSM_VerificationCandidate( String enrollmentID, String seedIndex ) {
this.enrollmentID = enrollmentID;
this.seedIndex = seedIndex;
}
public String enrollmentID;
public String seedIndex;
}
Here is main class where I have native method and from where I called that native method.
public class DsmLibraryTest extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
JCDSM_VerificationCandidate verificationCandidate[] = {new JCDSM_VerificationCandidate( "tom", "anna" )};
dsm.JD开发者_StackOverflowSMVerify( 123456, "http:\\www.test_url.com", bytes, verificationCandidate );
}
public native int JDSMVerify(
int someValue1,
String someValue2,
byte[] someValue3,
JC_VerificationCandidate jVerificationCandList[] );
}
As you can see I create array with one object and give it to my function.
JCDSM_VerificationCandidate verificationCandidate[] = {new JCDSM_VerificationCandidate( "tom", "anna" )};
JNI Code
How can I get that two strings enrollmentID
, eedIndex
that I have set from java application and which are stored in jVerificationCandList
?
JNIEXPORT jint JNICALL Java_com_Dsm_Test_DSM_JDSMVerify( JNIEnv* env, jobject thiz, jint jhDevice, jstring jurlID,
jbyteArray jInputInfo, jobjectArray jVerificationCandList ) {
}
The following code should allow you to access the field enrollmentID. Use the JNI String functions to read/manipulate them.
// Load the class
jclass jclass_JCV = env->FindClass(env, "my.package.JC_VerificationCandidate");
jfieldID fid_enrollmentID = env->GetFieldID(env, jclass_JCV, "enrollmentID" , "Ljava/lang/String;");
// Access the first element in the jVerificationCandList array
jobject jc_v = env->GetObjectArrayElement(env, jVerificationCandList, 0);
// get reference to the string
jstring jstr = (jstring) env->GetObjectField(env, jc_v, enrollmentID);
// Convert jstring to native string
const char *nativeString = env->GetStringUTFChars(env, jstr, 0);
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