Grails - Import data from excel spreadsheets

Importing data from excel spreadsheets to a grails application is quiet simple. You could your favorite spreadsheet processing libraries for Java like Jexcelapi or Apache POI.

In this example, I used Apache POI.

Step1: Copy the required libraries to libraries/lib folder of your grails applications.

Step2: Create a grails controller class. Eg: Uploader

def upload={

 
        def file = request.getFile('file')

        def fs = new POIFSFileSystem
              (file.getInputStream())

        def wb = new HSSFWorkbook(fs)

        def sheet = wb.getSheetAt(0)
        ...
        ...
        // Process the data from the sheet and save it in Grails domain objects

}

Step 3:

Create a gsp file with a form and a html file element to upload the file.

                <label for="file">File:</label>
                <input type="file" name="file" id="file"/>
                <input class="save" type="submit" value="Upload"/>
                

Note:
"controller" attribute of g:form is same as the controller used to handle the uploaded file.