Fix Open Office Spreadsheet (ODS) dates (#2843)

* Truncate any completely empty columns on the right

Fixes #565
The current versions of Open Office create default spreadsheets
with over 1000 empty columns. Keep track of the rightmost
non-empty column when importing and truncate everything else.

Also adds a basic ODS import test.

* Fix dates in ODS spreadsheets

Fixes #2224

main/src/com/google/refine/importers/OdsImporter.java

@@ -39,6 +39,7 @@ import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.Serializable;
+import java.time.ZoneOffset;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
@@ -216,7 +217,7 @@ public class OdsImporter extends TabularImportingParserBase {
         } else if ("float".equals(cellType)) {
             value = cell.getDoubleValue();
         } else if ("date".equals(cellType)) {
-            value = cell.getDateValue();
+            value = cell.getDateValue().toInstant().atOffset(ZoneOffset.UTC);
         } else if ("currency".equals(cellType)) {
             value = cell.getCurrencyValue();
         } else if ("percentage".equals(cellType)) {

main/tests/server/src/com/google/refine/importers/OdsImporterTests.java

@@ -43,6 +43,7 @@ import static org.testng.Assert.assertTrue;
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.InputStream;
+import java.time.OffsetDateTime;
 
 import org.slf4j.LoggerFactory;
 import org.testng.Assert;
@@ -109,8 +110,7 @@ public class OdsImporterTests extends ImporterTest {
         Row row = project.rows.get(0);
         assertEquals(row.cells.size(), COLUMNS);
         assertEquals((String)row.getCellValue(1),"2 Days In New York");
-        // FIXME: Dates are currently broken
-//        assertEquals(((OffsetDateTime)row.getCellValue(3)).toString().substring(0, 10),"2012-03-28");
+        assertEquals(((OffsetDateTime)row.getCellValue(3)).toString().substring(0, 10),"2012-03-28");
         assertEquals(((Number)row.getCellValue(5)).doubleValue(), 4.5, EPSILON);
 
         assertFalse((Boolean)row.getCellValue(7));