问题描述
(遍历模块)
long int
Traverser(const char * sTraversingRoot)
{
long int nCount;
struct stat rStatBuf;
time_t nTime;
char sActualPath[512];
PGconn *pConn;
// Open DB connection
sprintf(sConnInfo,
"hostaddr=%s port=%s connect_timeout=50 dbname=%s user=%s password=%s",
sIP, sPort, sDBName, sLogin, sPassword);
pConn = PQconnectdb(sConnInfo);
if (PQstatus(pConn) == CONNECTION_BAD) {
AddErrorToLog("No connect\n");
return 0;
}
GetActualPath(sActualPath, sTraversingRoot);
if (*sActualPath) {
stat(sActualPath, &rStatBuf);
} else {
stat("/", &rStatBuf);
}
if (nClock)
nTime = time(NULL);
if(S_ISREG(rStatBuf.st_mode)) {
nCount = 1;
ProcessFile(pConn, sActualPath);
}
if(S_ISDIR(rStatBuf.st_mode)) {
nCount = _Traverser(pConn, sActualPath);
}
if (nClock)
fprintf(stdout, "Total time : %u second(s)\n", time(NULL) - nTime);
// Close DB connection
PQfinish(pConn);
return nCount;
}
我想使用相同的名称创建一个Java上的方法
I want to create native with the same name a method on Java
public native void Traverser(String path)
分别在traverser.c模块中会有一个函数
Respectively in the traverser.c module there will be a function
JNIEXPORT void JNICALL Java_ParallelIndexation_Traverser(JNIEnv *env, jobject obj, jstring path)
Java_ParallelIndexation_Traverser函数是遍历器的Traverser函数包装器。问题是:如何从Java_ParallelIndexation_Traverser中的Traverser遍历器调用模块,传递参数jstring path,从而将其转换为const char *(签名Traverser见上文)?
The Java_ParallelIndexation_Traverser function is a Traverser function wrapper from the traverser.c module.The question is: How to call a module from Traverser traverser.c in Java_ParallelIndexation_Traverser, passing it the parameter jstring path, thus converting it to a const char * (signature Traverser see above)?
推荐答案
我正确理解你的问题:如何实现Java_ParallelIndexation_Traverser,以便它调用非托管Traveser函数?
Did I understand your question correctly: how to implement Java_ParallelIndexation_Traverser so that it calls the unmanaged Traveser function?
如果是这样,如下:
JNIEXPORT void JNICALL Java_ParallelIndexation_Traverser(JNIEnv* env, jobject obj, jstring path)
{
const jbyte* path2 = env->GetStringUTFChars(path, nullptr);
if (path2 == nullptr)
return;
::Traverser(path2);
env->ReleaseStringUTFChars(path, path2);
}
编辑:
说明:JNIEnv :: GetStringUTFChars将jstring转换为字节数组。然后需要调用JNIEnv :: ReleaseStringUTFChars来释放该字节数组。
Explanation: JNIEnv::GetStringUTFChars converts a jstring to a byte array. You then need to call JNIEnv::ReleaseStringUTFChars to deallocate that byte array.
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