Getting Files

To get files with the Documents and Media API, use a method from the getFileEntries or getGroupFileEntries method families discussed in Getting Entities. The steps here show you how, using this getFileEntries method as an example:

List<FileEntry> getFileEntries(
        long repositoryId, 
        long folderId, 
        String[] mimeTypes, 
        int start, 
        int end, 
        OrderByComparator<FileEntry> obc
)

For general information on using the Documents and Media API, see Documents and Media API.

Follow these steps to get a list of files. This example uses the above getFileEntries method to get all the PNG images from the root folder of a Site’s default repository, sorted by title:

1. Get a reference to DLAppService:

   @Reference
   private DLAppService _dlAppService;
   

2. Get the data needed to populate the method’s arguments. You can do this any way you wish. As the next step describes, Liferay DXP provides constants and a comparator for all the arguments this example needs besides the group ID. This example gets the group ID by using ParamUtil with the request (javax.portlet.ActionRequest):

   long groupId = ParamUtil.getLong(actionRequest, "groupId");
   

   It’s also possible to get the group ID via the ThemeDisplay. Calling the ThemeDisplay method getScopeGroupId() gets the ID of your app’s current site (group):

   ThemeDisplay themeDisplay = (ThemeDisplay) request.getAttribute(WebKeys.THEME_DISPLAY);
   long groupId = themeDisplay.getScopeGroupId();
   

3. Use the data from the previous step to call the service reference method you want to use to get the files. This example calls the above getFileEntries method with the group ID from the previous step, and constants and a comparator for the remaining arguments:

   List<FileEntry> fileEntries = 
           _dlAppService.getFileEntries(
                   groupId, 
                   DLFolderConstants.DEFAULT_PARENT_FOLDER_ID, 
                   new String[] {ContentTypes.IMAGE_PNG}, 
                   QueryUtil.ALL_POS, 
                   QueryUtil.ALL_POS, 
                   new RepositoryModelTitleComparator<>()
           );
   

   Here’s a description of the arguments used in this example:

   groupId: Using the group ID as the repository ID specifies that the operation takes place in the default site repository.

   DLFolderConstants.DEFAULT_PARENT_FOLDER_ID: Uses the DLFolderConstants constant DEFAULT_PARENT_FOLDER_ID to specify the repository’s root folder.

   new String[] {ContentTypes.IMAGE_PNG}: Uses the ContentTypes constant IMAGE_PNG to specify PNG images.

   QueryUtil.ALL_POS: Uses the QueryUtil constant ALL_POS for the start and end positions in the results. This specifies all results, bypassing pagination.

   new RepositoryModelTitleComparator<>(): Creates a new RepositoryModelTitleComparator, which sorts the results by title.

Remember, this is just one of many getFileEntries and getGroupFileEntries methods. To see all such methods, see the DLAppService Javadoc.

Related Topics

Getting Folders

Getting Multiple Entity Types