jna 获取文件作者

JNA（Java Native Access）是一个Java库，可以让Java应用程序调用本地的C/C++动态链接库（DLL/SO）。如果要获取文件作者，需要使用Windows API中的GetFileVersionInfo函数和VerQueryValue函数。可以通过JNA调用这些函数来实现。

以下是示例代码：

import com.sun.jna.Pointer;
import com.sun.jna.platform.win32.Version;

public class FileVersionInfo {

    public static void main(String[] args) {
        String fileName = "C:\\Windows\\System32\\notepad.exe";
        Version.VS_FIXEDFILEINFO fileInfo = getFileVersionInfo(fileName);
        if (fileInfo != null) {
            System.out.println("File version: " + fileInfo.dwFileVersionMS + "." + fileInfo.dwFileVersionLS);
            System.out.println("Product version: " + fileInfo.dwProductVersionMS + "." + fileInfo.dwProductVersionLS);
            String companyName = getStringFileInfo(fileName, "CompanyName");
            System.out.println("Company name: " + companyName);
            String fileDescription = getStringFileInfo(fileName, "FileDescription");
            System.out.println("File description: " + fileDescription);
            String fileVersion = getStringFileInfo(fileName, "FileVersion");
            System.out.println("File version string: " + fileVersion);
            String productName = getStringFileInfo(fileName, "ProductName");
            System.out.println("Product name: " + productName);
            String originalFilename = getStringFileInfo(fileName, "OriginalFilename");
            System.out.println("Original filename: " + originalFilename);
            String comments = getStringFileInfo(fileName, "Comments");
            System.out.println("Comments: " + comments);
        } else {
            System.out.println("File version info not found.");
        }
    }

    private static Version.VS_FIXEDFILEINFO getFileVersionInfo(String fileName) {
        Version version = Version.INSTANCE;
        int handle = version.GetFileVersionInfoSize(fileName, null);
        if (handle <= 0) {
            return null;
        }
        byte[] buffer = new byte[handle];
        if (!version.GetFileVersionInfo(fileName, 0, handle, buffer)) {
            return null;
        }
        Pointer pointer = new Pointer(0);
        int[] length = new int[1];
        if (!version.VerQueryValue(buffer, "\\", pointer, length)) {
            return null;
        }
        return new Version.VS_FIXEDFILEINFO(pointer.getByteArray(0, length[0]));
    }

    private static String getStringFileInfo(String fileName, String key) {
        Version version = Version.INSTANCE;
        int handle = version.GetFileVersionInfoSize(fileName, null);
        if (handle <= 0) {
            return null;
        }
        byte[] buffer = new byte[handle];
        if (!version.GetFileVersionInfo(fileName, 0, handle, buffer)) {
            return null;
        }
        Pointer pointer = new Pointer(0);
        int[] length = new int[1];
        if (!version.VerQueryValue(buffer, "\\StringFileInfo\\040904b0\\" + key, pointer, length)) {
            return null;
        }
        return pointer.getString(0);
    }

}

其中，`getFileVersionInfo`函数获取文件的版本信息，`getStringFileInfo`函数获取指定键的字符串信息。在`getStringFileInfo`函数中，`040904b0`是代表英语（美国）的语言和地区代码，可以根据需要修改。

注意，该代码只适用于Windows操作系统。如果要在其他操作系统上运行，需要使用不同的API函数。