有没有办法从 Dropbox 文件系统内的 pdf 中提取文本？

Question

I am working on a project where I need to iterate through a file system, extract text from a pdf, and scan through that text. Previously, the file system was an N drive (which acts as a local file system), so using the java File API, I could access each pdf file. Using this method, I would then extract the text:

public static String returnStringOfPDFiText(File file)
    {
        try {
        PdfReader reader = new PdfReader(file.getPath());
        int n = reader.getNumberOfPages();
        String pdfText = null;
        for(int i = 1; i<=n; i++)
        {
            pdfText += PdfTextExtractor.getTextFromPage(reader, n);
        }
        reader.close();
            System.out.println(pdfText);
            
            
            return pdfText;
        }
        catch(Exception e)
        {
            System.out.print(e);
            return null;
        }
        
    }

From here, I could scan through the text.

I now need to do this, but using a dropbox file system. I can only find a way to get the metadata of each file, though, and not the actual file, so I can extract text.

Is there a way to get the file so I can call this method on the file to extract the text, or to just extract the text directly from the dropbox file?

Edit: I am working with the DropboxAPI already (though I might be missing some methods, I haven't read through a lot of the documentation). I am aware of the download method, but I don't want to use it, since we will be working with around 1 gb of pdfs, and downloading it would be super inefficient.

Answer 1

Dropbox does offer an API you can use for listing, uploading, and downloading files, among other operations. You can find everything you need to get started with the Dropbox API, including documentation, tutorials, and SDKs here:

https://www.dropbox.com/developers

For Java specifically, we recommend you use the official Dropbox Java SDK:

https://github.com/dropbox/dropbox-sdk-java

To download a file's contents using that, you can use the download method:

https://dropbox.github.io/dropbox-sdk-java/api-docs/v5.2.0/com/dropbox/core/v2/files/DbxUserFilesRequests.html#download(java.lang.String)

You can find an example of that here:

https://github.com/dropbox/dropbox-sdk-java/blob/e52fc828c7c753e04c3fa9d47ab6de7e85d000c4/examples/tutorial/src/main/java/com/dropbox/core/examples/tutorial/Main.java#L54