cocos2dx 3.1 报dvmFindClassByName rejecting 'Ljava.lang.String;'

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借用网上char* 转jstring的函数时,在android平台运行后报上面的错误报错:

07-17 16:09:04.060: W/dalvikvm(7467): dvmFindClassByName rejecting 'Ljava.lang.String;'

07-17 16:09:04.060: A/libc(7467): Fatal signal 11 (SIGSEGV) at 0x0000002c (code=1)

原因是:

jclass strClass = (env)->FindClass("Ljava/lang/String;");这个在android里是找不到的

java中String的包名不是这个,而是java/lang/String

底下两个函数都可以用于char* 转jstring:

jstring CStr2Jstring( JNIEnv* env, const char* pat ) {   //定义java String类 strClass   jclass strClass = (env)->FindClass("<strong><em>java/lang/String</em></strong>");   //获取java String类方法String(byte[],String)的构造器,用于将本地byte[]数组转换为一个新String   jmethodID ctorID = (env)->GetMethodID(strClass, "<init>", "([BLjava/lang/String;)V");   //建立byte数组   jbyteArray bytes = (env)->NewByteArray((jsize)strlen(pat));   //将char* 转换为byte数组   (env)->SetByteArrayRegion(bytes, 0, (jsize)strlen(pat), (jbyte*)pat);   //设置String, 保存语言类型,用于byte数组转换至String时的参数   jstring encoding = (env)->NewStringUTF("GB2312");    //将byte数组转换为java String,并输出   return (jstring)(env)->NewObject(strClass, ctorID, bytes, encoding); } jstring chars2Jstring( JNIEnv* env, const char* pat ) {   //定义java String类 strClass  JniMethodInfo class_init;  //获取类的构造函数        if (JniHelper::getMethodInfo(class_init,"<strong><em>java/lang/String</em></strong>","<init>","([BLjava/lang/String;)V") == false)        {            CCLog("JniHelper::FindClass failed");            return nullptr;        }   //建立byte数组    jbyteArray bytes = (env)->NewByteArray((jsize)strlen(pat));   //将char* 转换为byte数组   (env)->SetByteArrayRegion(bytes, 0, (jsize)strlen(pat), (jbyte*)pat);   //设置String, 保存语言类型,用于byte数组转换至String时的参数   jstring encoding = (env)->NewStringUTF("GB2312");    //将byte数组转换为java String,并输出   return (jstring)(env)->NewObject(class_init.classID, class_init.methodID, bytes, encoding); }

下面是jstring转char*的函数

char* jstringTostring(JNIEnv* env, jstring jstr) {       char* rtn = NULL;       jclass clsstring = env->FindClass("java/lang/String");       jstring strencode = env->NewStringUTF("utf-8");       jmethodID mid = env->GetMethodID(clsstring, "getBytes", "(Ljava/lang/String;)[B");       jbyteArray barr= (jbyteArray)env->CallObjectMethod(jstr, mid, strencode);       jsize alen = env->GetArrayLength(barr);       jbyte* ba = env->GetByteArrayElements(barr, JNI_FALSE);       if (alen > 0)       {                 rtn = (char*)malloc(alen + 1);                 memcpy(rtn, ba, alen);                 rtn[alen] = 0;       }       env->ReleaseByteArrayElements(barr, ba, 0);       return rtn; }

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