How to get public Google Spreadsheet data using Google Spreadsheet API Java library without authentication

Question

-what I want to do

I would like to get data from Google Spreadsheet using Google Spreadsheet API Java library without authentication. The Google Spreadsheet is published with public. I would like to use the following method: com.google.gdata.data.spreadsheet.CustomElementCollection

-Issue

CustomElementCollection return collect data with authentication. But CustomElementCollection return null without authentication.

As listEntry.getPlainTextContent() shows data, so I think I should be able to get the data in any ways.

-Source code attached

With authentication: Auth.java

import java.net.URL;
import java.util.List;
import com.google.gdata.client.spreadsheet.ListQuery;
import com.google.gdata.client.spreadsheet.SpreadsheetService;
import com.google.gdata.data.spreadsheet.CustomElementCollection;
import com.google.gdata.data.spreadsheet.ListEntry;
import com.google.gdata.data.spreadsheet.ListFeed;
import com.google.gdata.data.spreadsheet.SpreadsheetEntry;
import com.google.gdata.data.spreadsheet.WorksheetEntry;

public class Auth {
    public static void main(String[] args) throws Exception{
        String applicationName = "AppName";
        String user = args[0];
        String pass = args[1];
        String key = args[2];
        String query = args[3];

        SpreadsheetService service = new SpreadsheetService(applicationName);
        service.setUserCredentials(user, pass); //set client auth 

        URL entryUrl = new URL("http://spreadsheets.google.com/feeds/spreadsheets/" + key);
        SpreadsheetEntry spreadsheetEntry = service.getEntry(entryUrl, SpreadsheetEntry.class);
        WorksheetEntry worksheetEntry = spreadsheetEntry.getDefaultWorksheet();

        ListQuery listQuery = new ListQuery(worksheetEntry.getListFeedUrl());
        listQuery.setSpreadsheetQuery( query );

        ListFeed listFeed = service.query(listQuery, ListFeed.class);
        List<ListEntry> list = listFeed.getEntries();
        for( ListEntry listEntry : list )
        {
            System.out.println( "content=[" + listEntry.getPlainTextContent() + "]");
            CustomElementCollection elements = listEntry.getCustomElements();
            System.out.println(
                    " name=" + elements.getValue("name") + 
                    " age="  + elements.getValue("age") );
        }
    }
}

Without authentication: NoAuth.java

import java.net.URL;
import java.util.List;
import com.google.gdata.client.spreadsheet.FeedURLFactory;
import com.google.gdata.client.spreadsheet.ListQuery;
import com.google.gdata.client.spreadsheet.SpreadsheetService;
import com.google.gdata.data.spreadsheet.CustomElementCollection;
import com.google.gdata.data.spreadsheet.ListEntry;
import com.google.gdata.data.spreadsheet.ListFeed;
import com.google.gdata.data.spreadsheet.WorksheetEntry;
import com.google.gdata.data.spreadsheet.WorksheetFeed;

public class NoAuth {
    public static void main(String[] args) throws Exception{
        String applicationName = "AppName";
        String key = args[0];
        String query = args[1];

        SpreadsheetService service = new SpreadsheetService(applicationName);

        URL url = FeedURLFactory.getDefault().getWorksheetFeedUrl(key, "public", "basic");

        WorksheetFeed feed = service.getFeed(url, WorksheetFeed.class);
        List<WorksheetEntry> worksheetList = feed.getEntries();
        WorksheetEntry worksheetEntry = worksheetList.get(0);

        ListQuery listQuery = new ListQuery(worksheetEntry.getListFeedUrl());
        listQuery.setSpreadsheetQuery( query );

        ListFeed listFeed = service.query( listQuery, ListFeed.class );
        List<ListEntry> list = listFeed.getEntries();
        for( ListEntry listEntry : list )
        {
            System.out.println( "content=[" + listEntry.getPlainTextContent() + "]");
            CustomElementCollection elements = listEntry.getCustomElements();
            System.out.println(
                    " name=" + elements.getValue("name") + 
                    " age="  + elements.getValue("age") );
        }
    }
}

Google Spreadsheet:

https://docs.google.com/spreadsheet/pub?key=0Ajawooo6A9OldHV0VHYzVVhTZlB6SHRjbGc5MG1CakE&output=html

-Result

Without authentication

　　　content=[age: 23] 　　　name=null age=null

With authentication

　　　content=[age: 23] 　　　name=Taro age=23

Please let me know the useful information to avoid the issue.

Answer 1

I don't know why it works like that, but when you don't access request with credentials, you are not able to retrieve cells via:

CustomElementCollection elements = listEntry.getCustomElements();
System.out.println(" name=" + elements.getValue("name") + " age="  + elements.getValue("age") );

I've tested it and I have found only this way to retrieve data:

List<ListEntry> list = listFeed.getEntries();
for (ListEntry row : list) {
    System.out.println(row.getTitle().getPlainText() + "\t"
            + row.getPlainTextContent());
}

It prints:

Taro    age: 23
Hanako  age: 16

As you see, you should parse text and retrieve age from raw String.

Answer 2

I believe the problem is that you are using the "basic" projection for your spreadsheet. If you use the "values" projection, everything should work as expected.

Answer 3

I was wondering about this as well. I looked at the feed coming in (just paste the URL to the sheet into Chrome), and it seems like there is no XML markup, and are all coming in under the <content> tag. So it makes sense that the parser is lumping it all into the text content of the BaseEntry (instead of making a ListEntry).