FileManager.java

import de.wirecard.epos.EposSDK;
import de.wirecard.epos.model.with.With;
import de.wirecard.epos.model.with.WithBase;
import de.wirecard.epos.model.with.WithFields;
import io.reactivex.android.schedulers.AndroidSchedulers;
import io.reactivex.schedulers.Schedulers;

//handling FileRecords
    WithFields withFields = With.fields().scheduler(Schedulers.newThread());
        epos.fileManager()
                .getFileRecord("fileId", withFields)
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(fileRecord -> {
                    // getFileRecord was performed successfully
                    // Single<FileRecords> is returned, you have now some basic information about this file
                }, throwable -> {
                    // handle error
                });


        epos.fileManager()
                .getFilesList("merchantId","categoryName", withFields)
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(fileRecordsList -> {
                    // getFilesList for merchant and category was performed successfully
                    // Single<List<FileRecords>> is returned, you have now all files aligned with specified merchnat and for mentioned category
                }, throwable -> {
                    // handle error
                });


        epos.fileManager()
                .getFilesCategories(withFields)
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(fileRecordCategoryList -> {
                    // getFilesCategories was performed successfully
                    // Single<List<FileRecordCategory>> is returned, you have now list of all categories
                }, throwable -> {
                    // handle error
                });

// Download particular file
        WithBase withBase = With.base().scheduler(Schedulers.io());
        epos.fileManager()
                .getFile("fileId",withBase)
                .observeOn(AndroidSchedulers.mainThread())
                .subscribe(fileRecordCategoryList -> {
                    // getFile was performed successfully
                    // Single<File> is returned, you can access to phisical file data
                }, throwable -> {
                    // handle error
                });