How to get all pdf file from google storage cloud bucket in JAVA

Question

In a bucket folder I can get pdf file from google storage. how can i download all files in ones from there. Eg.for a single file.

public InputStream getBlobBytesArray() {
    String bucketName ="XYZ";
    String filename="abc.pdf";
    Blob blob = getStorageInstance().get(BlobId.of(bucketName, filename));
    return  new ByteArrayInputStream(getStorageInstance().readAllBytes(blob.getBlobId()));

}

Inside the bucket I have create one folder where 5 pdf are store. How to fetch them all'

public MultipartFile getMultiFileFromCloud() {
        // TODO Auto-generated method stub
        String bucketName = "XYZ";
        Blob fileBlob = getStorageInstance().get(BlobId.of(bucketName, filepath));
        MultipartFile multipartFile = new CommonsMultipartFile( new ByteArrayInputStream(fileBlob.getContent(BlobSourceOption.generationMatch())));

        return null;
    }

I have tried this nothing working.thanks in advance.

Answer 1

Google storage provide the way to find out all objects inside the folder.

public InputStream getBlobBytesArray() {
    String bucketName ="XYZ";
Bucket bucket = storage.get(bucketName);

Page<Blob>blobs=bucket.list(Storage.BlobListOption.prefix("folderPath/1"));  
}

Now this is working fine for me.

Answer 2

You can search file only by prefix of their full name (path included). If you look for a suffix, or a content type metadata, you need to fetch all the files and select with your code what you want (the *.pdf extension in the name for example).

Then you can't download them in one command, but only one by one.