Java JNA：GetProcAddress returns 空

Question

以下代码无法找到 LoadLibraryW

private static FOREIGN_THREAD_START_ROUTINE getLoadLibraryWAddress() throws Win32Exception {
    HMODULE module = Kernel32.INSTANCE.GetModuleHandle("KERNEL32");
    if(module == null) {
        Win32Exception.throwWithLastError("Failed to find KERNEL32 module");
    }

    FOREIGN_THREAD_START_ROUTINE address = Kernel32MissingFunctions.INSTANCE.GetProcAddress(module, "LoadLibraryW");
    if(address == null) {
        Win32Exception.throwWithLastError("Failed to find LoadLibraryW in KERNEL32 module");
    }
    return address;
}

其中 GetProcAddress 声明如下：

public interface Kernel32MissingFunctions extends StdCallLibrary {

    Kernel32MissingFunctions INSTANCE = (Kernel32MissingFunctions) Native.loadLibrary("kernel32",
            Kernel32MissingFunctions.class, W32APIOptions.UNICODE_OPTIONS);

    public static final int MEM_RELEASE = 0x8000;

    public LPVOID VirtualAllocEx(HANDLE hProcess, LPVOID lpAddress, long dwSize, int flAllocationType, int flProtect);

    public int VirtualFreeEx(HANDLE hProcess, LPVOID lpAddress, long dwSize, int dwFreeType);

    public FOREIGN_THREAD_START_ROUTINE GetProcAddress(HMODULE hModule, String lpProcName);
}

有谁知道为什么？我的错误是什么？ 谢谢！

Answer 1

Martin Drab 是对的。使用 W32APIOptions.UNICODE_OPTIONS 将 Unicode 字符串传递给 Ansi 函数。如下更改接口修复了问题：

public interface Kernel32MissingFunctions extends StdCallLibrary {

    Kernel32MissingFunctions INSTANCE = (Kernel32MissingFunctions) Native.loadLibrary("kernel32",
            Kernel32MissingFunctions.class, W32APIOptions.ASCII_OPTIONS);

    public static final int MEM_RELEASE = 0x8000;

    public LPVOID VirtualAllocEx(HANDLE hProcess, LPVOID lpAddress, long dwSize, int flAllocationType, int flProtect);

    public int VirtualFreeEx(HANDLE hProcess, LPVOID lpAddress, long dwSize, int dwFreeType);

    public LPVOID GetProcAddress(HMODULE hModule, String lpProcName);
}