Support for specifying a policy to HSSF on missing / blank cells when fetching

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@658308 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Nick Burch 2008-05-20 16:30:19 +00:00
parent 40bb917404
commit 2e8acca69b
4 changed files with 115 additions and 0 deletions

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@ -37,6 +37,7 @@
<!-- Don't forget to update status.xml too! -->
<release version="3.1-final" date="2008-06-??">
<action dev="POI-DEVELOPERS" type="add">Support for specifying a policy to HSSF on missing / blank cells when fetching</action>
<action dev="POI-DEVELOPERS" type="add">44937 - Partial support for extracting Escher images from HWPF files</action>
<action dev="POI-DEVELOPERS" type="fix">44824 - Avoid an infinite loop when reading some HWPF pictures</action>
<action dev="POI-DEVELOPERS" type="fix">44898 - Correctly handle short last blocks in POIFS</action>

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@ -34,6 +34,7 @@
<!-- Don't forget to update changes.xml too! -->
<changes>
<release version="3.1-final" date="2008-06-??">
<action dev="POI-DEVELOPERS" type="add">Support for specifying a policy to HSSF on missing / blank cells when fetching</action>
<action dev="POI-DEVELOPERS" type="add">44937 - Partial support for extracting Escher images from HWPF files</action>
<action dev="POI-DEVELOPERS" type="fix">44824 - Avoid an infinite loop when reading some HWPF pictures</action>
<action dev="POI-DEVELOPERS" type="fix">44898 - Correctly handle short last blocks in POIFS</action>

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@ -300,6 +300,36 @@ public final class HSSFRow implements Comparable {
if(cellnum<0||cellnum>=cells.length) return null;
return cells[cellnum];
}
/**
* Get the hssfcell representing a given column (logical cell)
* 0-based. If you ask for a cell that is not defined, then
* your supplied policy says what to do
*
* @param cellnum 0 based column number
* @param policy Policy on blank / missing cells
* @return representing that column or null if undefined + policy allows.
*/
public HSSFCell getCell(int cellnum, MissingCellPolicy policy) {
HSSFCell cell = getCell(cellnum);
if(policy == RETURN_NULL_AND_BLANK) {
return cell;
}
if(policy == RETURN_BLANK_AS_NULL) {
if(cell == null) return cell;
if(cell.getCellType() == HSSFCell.CELL_TYPE_BLANK) {
return null;
}
return cell;
}
if(policy == CREATE_NULL_AS_BLANK) {
if(cell == null) {
return createCell((short)cellnum, HSSFCell.CELL_TYPE_BLANK);
}
return cell;
}
throw new IllegalArgumentException("Illegal policy " + policy + " (" + policy.id + ")");
}
/**
* get the number of the first cell contained in this row.
@ -466,6 +496,26 @@ public final class HSSFRow implements Comparable {
return cellnum;
}
/**
* Used to specify the different possible policies
* if for the case of null and blank cells
*/
public static class MissingCellPolicy {
private static int NEXT_ID = 1;
private final int id;
private MissingCellPolicy() {
this.id = NEXT_ID++;
}
}
/** Missing cells are returned as null, Blank cells are returned as normal */
public static final MissingCellPolicy RETURN_NULL_AND_BLANK = new MissingCellPolicy();
/** Missing cells are returned as null, as are blank cells */
public static final MissingCellPolicy RETURN_BLANK_AS_NULL = new MissingCellPolicy();
/** A new, blank cell is created for missing cells. Blank cells are returned as normal */
public static final MissingCellPolicy CREATE_NULL_AS_BLANK = new MissingCellPolicy();
/**
* @return cell iterator of the physically defined cells.
* Note that the 4th element might well not be cell 4, as the iterator
@ -484,6 +534,9 @@ public final class HSSFRow implements Comparable {
return cellIterator();
}
/**
* An iterator over the (physical) cells in the row.
*/
private class CellIterator implements Iterator
{
int thisId=-1;

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@ -204,4 +204,64 @@ public final class TestHSSFRow extends TestCase {
row.createCell((short) 255);
assertEquals(256, row.getLastCellNum());
}
/**
* Tests for the missing/blank cell policy stuff
*/
public void testGetCellPolicy() throws Exception {
HSSFWorkbook book = new HSSFWorkbook();
HSSFSheet sheet = book.createSheet("test");
HSSFRow row = sheet.createRow(0);
// 0 -> string
// 1 -> num
// 2 missing
// 3 missing
// 4 -> blank
// 5 -> num
row.createCell((short)0).setCellValue(new HSSFRichTextString("test"));
row.createCell((short)1).setCellValue(3.2);
row.createCell((short)4, HSSFCell.CELL_TYPE_BLANK);
row.createCell((short)5).setCellValue(4);
// First up, no policy
assertEquals(HSSFCell.CELL_TYPE_STRING, row.getCell(0).getCellType());
assertEquals(HSSFCell.CELL_TYPE_NUMERIC, row.getCell(1).getCellType());
assertEquals(null, row.getCell(2));
assertEquals(null, row.getCell(3));
assertEquals(HSSFCell.CELL_TYPE_BLANK, row.getCell(4).getCellType());
assertEquals(HSSFCell.CELL_TYPE_NUMERIC, row.getCell(5).getCellType());
// RETURN_NULL_AND_BLANK - same as default
assertEquals(HSSFCell.CELL_TYPE_STRING, row.getCell(0, HSSFRow.RETURN_NULL_AND_BLANK).getCellType());
assertEquals(HSSFCell.CELL_TYPE_NUMERIC, row.getCell(1, HSSFRow.RETURN_NULL_AND_BLANK).getCellType());
assertEquals(null, row.getCell(2, HSSFRow.RETURN_NULL_AND_BLANK));
assertEquals(null, row.getCell(3, HSSFRow.RETURN_NULL_AND_BLANK));
assertEquals(HSSFCell.CELL_TYPE_BLANK, row.getCell(4, HSSFRow.RETURN_NULL_AND_BLANK).getCellType());
assertEquals(HSSFCell.CELL_TYPE_NUMERIC, row.getCell(5, HSSFRow.RETURN_NULL_AND_BLANK).getCellType());
// RETURN_BLANK_AS_NULL - nearly the same
assertEquals(HSSFCell.CELL_TYPE_STRING, row.getCell(0, HSSFRow.RETURN_BLANK_AS_NULL).getCellType());
assertEquals(HSSFCell.CELL_TYPE_NUMERIC, row.getCell(1, HSSFRow.RETURN_BLANK_AS_NULL).getCellType());
assertEquals(null, row.getCell(2, HSSFRow.RETURN_BLANK_AS_NULL));
assertEquals(null, row.getCell(3, HSSFRow.RETURN_BLANK_AS_NULL));
assertEquals(null, row.getCell(4, HSSFRow.RETURN_BLANK_AS_NULL));
assertEquals(HSSFCell.CELL_TYPE_NUMERIC, row.getCell(5, HSSFRow.RETURN_BLANK_AS_NULL).getCellType());
// CREATE_NULL_AS_BLANK - creates as needed
assertEquals(HSSFCell.CELL_TYPE_STRING, row.getCell(0, HSSFRow.CREATE_NULL_AS_BLANK).getCellType());
assertEquals(HSSFCell.CELL_TYPE_NUMERIC, row.getCell(1, HSSFRow.CREATE_NULL_AS_BLANK).getCellType());
assertEquals(HSSFCell.CELL_TYPE_BLANK, row.getCell(2, HSSFRow.CREATE_NULL_AS_BLANK).getCellType());
assertEquals(HSSFCell.CELL_TYPE_BLANK, row.getCell(3, HSSFRow.CREATE_NULL_AS_BLANK).getCellType());
assertEquals(HSSFCell.CELL_TYPE_BLANK, row.getCell(4, HSSFRow.CREATE_NULL_AS_BLANK).getCellType());
assertEquals(HSSFCell.CELL_TYPE_NUMERIC, row.getCell(5, HSSFRow.CREATE_NULL_AS_BLANK).getCellType());
// Check created ones get the right column
assertEquals((short)0, row.getCell(0, HSSFRow.CREATE_NULL_AS_BLANK).getCellNum());
assertEquals((short)1, row.getCell(1, HSSFRow.CREATE_NULL_AS_BLANK).getCellNum());
assertEquals((short)2, row.getCell(2, HSSFRow.CREATE_NULL_AS_BLANK).getCellNum());
assertEquals((short)3, row.getCell(3, HSSFRow.CREATE_NULL_AS_BLANK).getCellNum());
assertEquals((short)4, row.getCell(4, HSSFRow.CREATE_NULL_AS_BLANK).getCellNum());
assertEquals((short)5, row.getCell(5, HSSFRow.CREATE_NULL_AS_BLANK).getCellNum());
}
}