在图片不正确的情况下jni库崩溃

[hiroyukki]

jni导出未 catch 异常，导致了如果传入一个非正确的图片(如 docx 改名为 png)，jvm 崩溃，因为在 java 中无法捕获 c++ exception
可在 jni 接口中捕获异常，异常情况视为未检测到文字：
`

extern "C" JNIEXPORT jobject JNICALL
Java_com_benjaminwan_ocrlibrary_OcrEngine_detect(JNIEnv *env, jobject thiz, jstring input, jint padding,
jint maxSideLen,
jfloat boxScoreThresh, jfloat boxThresh, jfloat unClipRatio,
jboolean doAngle, jboolean mostAngle
) {

std::string imgPath = jstringToChar(env, input);
bool hasTargetImgFile = isFileExists(imgPath);
if (!hasTargetImgFile) {
    fprintf(stderr, "Target image not found: %s\n", imgPath.c_str());
    OcrResult result{};
    return OcrResultUtils(env, result).getJObject();
}
std::string imgDir = imgPath.substr(0, imgPath.find_last_of('/') + 1);
std::string imgName = imgPath.substr(imgPath.find_last_of('/') + 1);
printf("imgDir=%s, imgName=%s\n", imgDir.c_str(), imgName.c_str());

try {
	OcrResult result = ocrLite->detect(imgDir.c_str(), imgName.c_str(), padding, maxSideLen,
		boxScoreThresh, boxThresh, unClipRatio, doAngle, mostAngle);
	return OcrResultUtils(env, result).getJObject();
} catch (...) {
	OcrResult result{};
	return OcrResultUtils(env, result).getJObject();
}

}

`