Make XSSF and HSSF consistent in getMergedRegions - return empty list if there are none, rather than an exception. Tests for this.

https://bz.apache.org/bugzilla/show_bug.cgi?id=58350

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1704839 13f79535-47bb-0310-9956-ffa450edef68

3 files changed, 16 insertions, 4 deletions

diff --git a/src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFSheet.java b/src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFSheet.java
index 4156433bd4..728fedf86a 100644
--- a/src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFSheet.java
+++ b/src/ooxml/java/org/apache/poi/xssf/usermodel/XSSFSheet.java
@@ -1090,7 +1090,6 @@ public class XSSFSheet extends POIXMLDocumentPart implements Sheet {
      * this each time.
      *
      * @return the merged region at the specified index
-     * @throws IllegalStateException if this worksheet does not contain merged regions
      */
     @Override
     public CellRangeAddress getMergedRegion(int index) {
@@ -1107,15 +1106,14 @@ public class XSSFSheet extends POIXMLDocumentPart implements Sheet {
      * faster than calling {@link #getMergedRegion(int)} each time.
      *
      * @return the list of merged regions
-     * @throws IllegalStateException if this worksheet does not contain merged regions
      */
     @SuppressWarnings("deprecation")
     @Override
     public List<CellRangeAddress> getMergedRegions() {
+        List<CellRangeAddress> addresses = new ArrayList<CellRangeAddress>();
         CTMergeCells ctMergeCells = worksheet.getMergeCells();
-        if(ctMergeCells == null) throw new IllegalStateException("This worksheet does not contain merged regions");
+        if(ctMergeCells == null) return addresses;
 
-        List<CellRangeAddress> addresses = new ArrayList<CellRangeAddress>();
         for(CTMergeCell ctMergeCell : ctMergeCells.getMergeCellArray()) {
             String ref = ctMergeCell.getRef();
             addresses.add(CellRangeAddress.valueOf(ref));
diff --git a/src/ooxml/testcases/org/apache/poi/xssf/usermodel/TestXSSFSheet.java b/src/ooxml/testcases/org/apache/poi/xssf/usermodel/TestXSSFSheet.java
index 8e77b2c499..aed4465620 100644
--- a/src/ooxml/testcases/org/apache/poi/xssf/usermodel/TestXSSFSheet.java
+++ b/src/ooxml/testcases/org/apache/poi/xssf/usermodel/TestXSSFSheet.java
@@ -1382,4 +1382,11 @@ public final class TestXSSFSheet extends BaseTestSheet {
         XSSFSheet sheet = wb.createSheet();
         assertNotNull(sheet.createComment());
     }
+
+    @Test
+    public void testNoMergedRegionsIsEmptyList() {
+        XSSFWorkbook wb = new XSSFWorkbook();
+        XSSFSheet sheet = wb.createSheet();
+        assertTrue(sheet.getMergedRegions().isEmpty());
+    }
 }
\ No newline at end of file
diff --git a/src/testcases/org/apache/poi/hssf/usermodel/TestHSSFSheet.java b/src/testcases/org/apache/poi/hssf/usermodel/TestHSSFSheet.java
index 4b7d8491be..723bf0d3e9 100644
--- a/src/testcases/org/apache/poi/hssf/usermodel/TestHSSFSheet.java
+++ b/src/testcases/org/apache/poi/hssf/usermodel/TestHSSFSheet.java
@@ -657,6 +657,13 @@ public final class TestHSSFSheet extends BaseTestSheet {
         assertTrue(sheet3.getColumnWidth(0) >= minWithRow1And2);
         assertTrue(sheet3.getColumnWidth(0) <= maxWithRow1And2);
     }
+
+    @Test
+    public void testNoMergedRegionsIsEmptyList() {
+        HSSFWorkbook wb = new HSSFWorkbook();
+        HSSFSheet s = wb.createSheet("Sheet1");
+        assertTrue(s.getMergedRegions().isEmpty());
+    }
     
     @Test
     public void autoSizeDate() throws Exception {