JNI：将字节从 C++ 传递到 Java
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JNI: passing bytes from c++ to java
提问by justme_
HANDLE hFile = CreateFileA("C:\myfile.zip", GENERIC_READ, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
const int size = GetFileSize(hFile, NULL);
char* buffer = new char[size];
DWORD read;
ReadFile(hFile, buffer, size, &read, NULL);
jclass cls = ...;
jmethodID id = ...;
jbyteArray arr = env->NewByteArray(size);
env->GetByteArrayRegion(arr, 0, size, (jbyte*) buffer);
env->CallStaticVoidMethod(cls, id, arr);
problem is that byte array contains just null bytes in java side, does anyone have idea why?
问题是字节数组在java端只包含空字节，有人知道为什么吗？
EDIT: oh my bad it should be SetByteArrayRegion, sorry! all working now :)
编辑：哦，我的错应该是 SetByteArrayRegion，对不起！现在都在工作:)
回答by Jason Rogers
I think your missing a line like :
我认为你错过了这样的一行：
(*env)-> SetByteArrayRegion(env, result, 0, size, fill);
check out :
查看 ：
http://java.sun.com/developer/onlineTraining/Programming/JDCBook/jnistring.html
http://java.sun.com/developer/onlineTraining/Programming/JDCBook/jnistring.html
for more details
更多细节
also a similar question was answered here
也在这里回答了类似的问题
