Android — вызов getWritableDatabase (Java-метод SQLCipher) из JNI

У меня есть код Java, чтобы открыть базу данных SqlCipher. Я хочу позвонить getWritableDatabase функция от JNI скрыть пароль

Произошла ошибка при звонке getWritableDatabas метод из SQLiteOpenHelper класс в Java_com_company_pos_DbHelper_getWritableSqlite метод (sqlauth.cpp), что не так с моим кодом?

DbHelper.java

public class DbHelper extends SQLiteOpenHelper {
//private final static String PASSWORD= "MyPassword"private final static String TAG = "DbHelper";
private static SQLiteDatabase db = null;

/* This method works only password is not secure.
public void open() {
try {
//The password isn't hidden
db = getWritableDatabase(PASSWORD);
} catch (SQLiteException e) {
Log.e(TAG, e.getMessage());
}
}
*/

static {
System.loadLibrary("sqlauth");
}

private native SQLiteDatabase getWritableSqlite();

public void open() {
try {
//The password is hidden in jNI
db = getWritableSqlite();
} catch (SQLiteException e) {
Log.e(TAG, e.getMessage());
}
}

}

JNI

sqlauth.h

#include <jni.h>
#include <string.h>
#include <iostream>

#ifndef SQLAUTH_H
#define SQLAUTH_H
#endif

static char *CLS_SQLITEOPENHELPER = (char *) "net/sqlcipher/database/SQLiteOpenHelper";
static char *MID_GETWRITABLEDATABASE = (char *) "getWritableDatabase";
static char *SIG_GETWRITABLEDATABASE = (char *) "(Ljava/lang/String;)Lnet/sqlcipher/database/SQLiteDatabase;";

#ifdef __cplusplus
extern "C" {
#endif

JavaVM *_jvm;
jclass _clsSQLiteOpenHelper;
jobject _objGetWritableDatabase;
jmethodID _midGetWritableDatabase;

JNIEnv *getEnv();
jboolean tryCatch();
JNIEXPORT jint JNICALL JNI_OnLoad(JavaVM *jvm, void *reserved);
JNIEXPORT void JNICALL JNI_OnUnload(JavaVM *jvm, void *reserved);
JNIEXPORT jobject JNICALL Java_com_company_pos_DbHelper_getWritableSqlite(JNIEnv *e, jobject obj);

#ifdef __cplusplus
}
#endif

sqlauth.cpp

#include "sqlauth.h"
#ifdef __cplusplus
extern "C" {
#endif

JNIEnv *getEnv() {
JNIEnv *env;
_jvm->GetEnv((void **) &env, JNI_VERSION_1_6);

return env;
}

jboolean tryCatch() {
JNIEnv *env = getEnv();
if (env == NULL) {
return JNI_TRUE;
}

jthrowable ex = env->ExceptionOccurred();
if (ex) {
env->ExceptionClear();
return JNI_TRUE;
}
return JNI_FALSE;
}

JNIEXPORT jint JNICALL
JNI_OnLoad(JavaVM *jvm, void *reserved) {
JNIEnv *env;
jclass clsDbHelper, clsSqliteDatabase, clsSQLiteOpenHelper;

_jvm = jvm;
if (jvm->GetEnv((void **) &env, JNI_VERSION_1_6)) {
return JNI_ERR;
}

// SQLiteOpenHelper.java
clsSQLiteOpenHelper = env->FindClass(CLS_SQLITEOPENHELPER);
if (clsSQLiteOpenHelper == NULL) {
return JNI_ERR;
}
_clsSQLiteOpenHelper = (jclass) env->NewWeakGlobalRef(clsSQLiteOpenHelper);
if (_clsSQLiteOpenHelper == NULL) {
return JNI_ERR;
}
_midGetWritableDatabase = env->GetMethodID(_clsSQLiteOpenHelper, MID_GETWRITABLEDATABASE, SIG_GETWRITABLEDATABASE);
if (_midGetWritableDatabase == NULL) {
return JNI_ERR;
}
return JNI_VERSION_1_6;
}

JNIEXPORT void JNICALL
JNI_OnUnload(JavaVM *jvm, void *reserved) {
JNIEnv *env;

if (jvm->GetEnv((void **) &env, JNI_VERSION_1_6)) {
return;
}
env->DeleteWeakGlobalRef(_clsSQLiteOpenHelper);
return;
}

JNIEXPORT jobject JNICALL
Java_com_company_pos_DbHelper_getWritableSqlite(JNIEnv *e, jobject obj) {
JNIEnv *env = getEnv();
if (env == NULL || obj == NULL) {
return NULL;
}

// Error in here when calling getWritableDatabase
// from net/sqlcipher/database/SQLiteOpenHelper
_objGetWritableDatabase = env->CallObjectMethod(_clsSQLiteOpenHelper, _midGetWritableDatabase, env->NewStringUTF("MyPassword"));
if (_objGetWritableDatabase == NULL || tryCatch()) {
return NULL; // Program stop in here.
}
return _objGetWritableDatabase;
}

#ifdef __cplusplus
}
#endif

SQLiteOpenHelper.class

public synchronized SQLiteDatabase getWritableDatabase(String password) {
return this.getWritableDatabase(password == null?null:password.toCharArray());
}