Java tutorial
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See the License for the specific language governing permissions and limitations under the License. ==================================================================== */ package utilities; import static org.apache.poi.xssf.usermodel.XSSFRelation.NS_SPREADSHEETML; import java.text.SimpleDateFormat; import java.util.Date; import java.util.Iterator; import java.util.LinkedList; import java.util.Queue; import org.apache.poi.ss.usermodel.BuiltinFormats; import org.apache.poi.ss.usermodel.DataFormatter; import org.apache.poi.ss.usermodel.DateUtil; import org.apache.poi.ss.usermodel.ExcelNumberFormat; import org.apache.poi.ss.usermodel.RichTextString; import org.apache.poi.ss.util.CellAddress; import org.apache.poi.util.POILogFactory; import org.apache.poi.util.POILogger; import org.apache.poi.xssf.model.*; import org.apache.poi.xssf.usermodel.XSSFCellStyle; import org.apache.poi.xssf.usermodel.XSSFComment; import org.apache.poi.xssf.usermodel.XSSFRichTextString; import org.xml.sax.Attributes; import org.xml.sax.SAXException; import org.xml.sax.helpers.DefaultHandler; /** * This class handles the processing of a sheet#.xml * sheet part of a XSSF .xlsx file, and generates * row and cell events for it. */ public class SmapSheetXMLHandler extends DefaultHandler { private static final POILogger logger = POILogFactory.getLogger(SmapSheetXMLHandler.class); /** * These are the different kinds of cells we support. * We keep track of the current one between * the start and end. */ enum xssfDataType { BOOLEAN, ERROR, FORMULA, INLINE_STRING, SST_STRING, NUMBER, } /** * Table with the styles used for formatting */ private Styles stylesTable; /** * Table with cell comments */ private Comments comments; /** * Read only access to the shared strings table, for looking * up (most) string cell's contents */ private SharedStrings sharedStringsTable; /** * Where our text is going */ private final SheetContentsHandler output; // Set when V start element is seen private boolean vIsOpen; // Set when F start element is seen private boolean fIsOpen; // Set when an Inline String "is" is seen private boolean isIsOpen; // Set when a header/footer element is seen private boolean hfIsOpen; // Set when cell start element is seen; // used when cell close element is seen. private xssfDataType nextDataType; // Used to format numeric cell values. private XSSFCellStyle style; private short formatIndex; private String formatString; private final DataFormatter formatter; private int rowNum; private int nextRowNum; // some sheets do not have rowNums, Excel can read them so we should try to handle them correctly as well private String cellRef; private boolean formulasNotResults; private SimpleDateFormat sdf; // Gathers characters as they are seen. private StringBuilder value = new StringBuilder(64); private StringBuilder formula = new StringBuilder(64); private StringBuilder headerFooter = new StringBuilder(64); private Queue<CellAddress> commentCellRefs; /** * Accepts objects needed while parsing. * * @param styles Table of styles * @param strings Table of shared strings */ public SmapSheetXMLHandler(Styles styles, Comments comments, SharedStrings strings, SheetContentsHandler sheetContentsHandler, DataFormatter dataFormatter, boolean formulasNotResults, SimpleDateFormat sdf) { this.stylesTable = styles; this.comments = comments; this.sharedStringsTable = strings; this.output = sheetContentsHandler; this.formulasNotResults = formulasNotResults; this.nextDataType = xssfDataType.NUMBER; this.formatter = dataFormatter; this.sdf = sdf; init(comments); } /** * Accepts objects needed while parsing. * * @param styles Table of styles * @param strings Table of shared strings */ public SmapSheetXMLHandler(Styles styles, SharedStrings strings, SheetContentsHandler sheetContentsHandler, DataFormatter dataFormatter, boolean formulasNotResults, SimpleDateFormat sdf) { this(styles, null, strings, sheetContentsHandler, dataFormatter, formulasNotResults, sdf); } /** * Accepts objects needed while parsing. * * @param styles Table of styles * @param strings Table of shared strings */ public SmapSheetXMLHandler(Styles styles, SharedStrings strings, SheetContentsHandler sheetContentsHandler, boolean formulasNotResults, SimpleDateFormat sdf) { this(styles, strings, sheetContentsHandler, new DataFormatter(), formulasNotResults, sdf); } private void init(Comments commentsTable) { if (commentsTable != null) { commentCellRefs = new LinkedList<>(); for (Iterator<CellAddress> iter = commentsTable.getCellAddresses(); iter.hasNext();) { commentCellRefs.add(iter.next()); } } } private boolean isTextTag(String name) { if ("v".equals(name)) { // Easy, normal v text tag return true; } if ("inlineStr".equals(name)) { // Easy inline string return true; } if ("t".equals(name) && isIsOpen) { // Inline string <is><t>...</t></is> pair return true; } // It isn't a text tag return false; } @Override @SuppressWarnings("unused") public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException { if (uri != null && !uri.equals(NS_SPREADSHEETML)) { return; } if (isTextTag(localName)) { vIsOpen = true; // Clear contents cache value.setLength(0); } else if ("is".equals(localName)) { // Inline string outer tag isIsOpen = true; } else if ("f".equals(localName)) { // Clear contents cache formula.setLength(0); // Mark us as being a formula if not already if (nextDataType == xssfDataType.NUMBER) { nextDataType = xssfDataType.FORMULA; } // Decide where to get the formula string from String type = attributes.getValue("t"); if (type != null && type.equals("shared")) { // Is it the one that defines the shared, or uses it? String ref = attributes.getValue("ref"); String si = attributes.getValue("si"); if (ref != null) { // This one defines it // TODO Save it somewhere fIsOpen = true; } else { // This one uses a shared formula // TODO Retrieve the shared formula and tweak it to // match the current cell if (formulasNotResults) { logger.log(POILogger.WARN, "shared formulas not yet supported!"); } /*else { // It's a shared formula, so we can't get at the formula string yet // However, they don't care about the formula string, so that's ok! }*/ } } else { fIsOpen = true; } } else if ("oddHeader".equals(localName) || "evenHeader".equals(localName) || "firstHeader".equals(localName) || "firstFooter".equals(localName) || "oddFooter".equals(localName) || "evenFooter".equals(localName)) { hfIsOpen = true; // Clear contents cache headerFooter.setLength(0); } else if ("row".equals(localName)) { String rowNumStr = attributes.getValue("r"); if (rowNumStr != null) { rowNum = Integer.parseInt(rowNumStr) - 1; } else { rowNum = nextRowNum; } output.startRow(rowNum); } // c => cell else if ("c".equals(localName)) { // Set up defaults. this.nextDataType = xssfDataType.NUMBER; this.formatIndex = -1; this.formatString = null; cellRef = attributes.getValue("r"); String cellType = attributes.getValue("t"); String cellStyleStr = attributes.getValue("s"); if ("b".equals(cellType)) nextDataType = xssfDataType.BOOLEAN; else if ("e".equals(cellType)) nextDataType = xssfDataType.ERROR; else if ("inlineStr".equals(cellType)) nextDataType = xssfDataType.INLINE_STRING; else if ("s".equals(cellType)) nextDataType = xssfDataType.SST_STRING; else if ("str".equals(cellType)) nextDataType = xssfDataType.FORMULA; else { // Number, but almost certainly with a special style or format style = null; if (stylesTable != null) { if (cellStyleStr != null) { int styleIndex = Integer.parseInt(cellStyleStr); style = stylesTable.getStyleAt(styleIndex); } else if (stylesTable.getNumCellStyles() > 0) { style = stylesTable.getStyleAt(0); } } if (style != null) { this.formatIndex = style.getDataFormat(); this.formatString = style.getDataFormatString(); if (this.formatString == null) this.formatString = BuiltinFormats.getBuiltinFormat(this.formatIndex); } } } } @Override public void endElement(String uri, String localName, String qName) throws SAXException { if (uri != null && !uri.equals(NS_SPREADSHEETML)) { return; } String thisStr = null; // v => contents of a cell if (isTextTag(localName)) { vIsOpen = false; // Process the value contents as required, now we have it all switch (nextDataType) { case BOOLEAN: char first = value.charAt(0); thisStr = first == '0' ? "FALSE" : "TRUE"; break; case ERROR: thisStr = "ERROR:" + value; break; case FORMULA: if (formulasNotResults) { thisStr = formula.toString(); } else { String fv = value.toString(); if (this.formatString != null) { try { // Try to use the value as a formattable number double d = Double.parseDouble(fv); thisStr = formatter.formatRawCellContents(d, this.formatIndex, this.formatString); } catch (NumberFormatException e) { // Formula is a String result not a Numeric one thisStr = fv; } } else { // No formatting applied, just do raw value in all cases thisStr = fv; } } break; case INLINE_STRING: // TODO: Can these ever have formatting on them? XSSFRichTextString rtsi = new XSSFRichTextString(value.toString()); thisStr = rtsi.toString(); break; case SST_STRING: String sstIndex = value.toString(); try { int idx = Integer.parseInt(sstIndex); RichTextString rtss = sharedStringsTable.getItemAt(idx); thisStr = rtss.toString(); } catch (NumberFormatException ex) { logger.log(POILogger.ERROR, "Failed to parse SST index '" + sstIndex, ex); } break; case NUMBER: String n = value.toString(); if (this.formatString != null && n.length() > 0) { // smap Check for date boolean isDate = false; double d = Double.parseDouble(n); if (DateUtil.isValidExcelDate(d)) { ExcelNumberFormat nf = ExcelNumberFormat.from(style); if (nf != null) { isDate = DateUtil.isADateFormat(nf); } } if (isDate) { try { Date dv = DateUtil.getJavaDate(d); thisStr = sdf.format(dv); } catch (Exception e) { } } else { thisStr = formatter.formatRawCellContents(Double.parseDouble(n), this.formatIndex, this.formatString); } } else thisStr = n; break; default: thisStr = "(TODO: Unexpected type: " + nextDataType + ")"; break; } // Do we have a comment for this cell? checkForEmptyCellComments(EmptyCellCommentsCheckType.CELL); XSSFComment comment = comments != null ? comments.findCellComment(new CellAddress(cellRef)) : null; // Output output.cell(cellRef, thisStr, comment, nextDataType, formatString); } else if ("f".equals(localName)) { fIsOpen = false; } else if ("is".equals(localName)) { isIsOpen = false; } else if ("row".equals(localName)) { // Handle any "missing" cells which had comments attached checkForEmptyCellComments(EmptyCellCommentsCheckType.END_OF_ROW); // Finish up the row output.endRow(rowNum); // some sheets do not have rowNum set in the XML, Excel can read them so we should try to read them as well nextRowNum = rowNum + 1; } else if ("sheetData".equals(localName)) { // Handle any "missing" cells which had comments attached checkForEmptyCellComments(EmptyCellCommentsCheckType.END_OF_SHEET_DATA); // indicate that this sheet is now done output.endSheet(); } else if ("oddHeader".equals(localName) || "evenHeader".equals(localName) || "firstHeader".equals(localName)) { hfIsOpen = false; output.headerFooter(headerFooter.toString(), true, localName); } else if ("oddFooter".equals(localName) || "evenFooter".equals(localName) || "firstFooter".equals(localName)) { hfIsOpen = false; output.headerFooter(headerFooter.toString(), false, localName); } } /** * Captures characters only if a suitable element is open. * Originally was just "v"; extended for inlineStr also. */ @Override public void characters(char[] ch, int start, int length) throws SAXException { if (vIsOpen) { value.append(ch, start, length); } if (fIsOpen) { formula.append(ch, start, length); } if (hfIsOpen) { headerFooter.append(ch, start, length); } } /** * Do a check for, and output, comments in otherwise empty cells. */ private void checkForEmptyCellComments(EmptyCellCommentsCheckType type) { if (commentCellRefs != null && !commentCellRefs.isEmpty()) { // If we've reached the end of the sheet data, output any // comments we haven't yet already handled if (type == EmptyCellCommentsCheckType.END_OF_SHEET_DATA) { while (!commentCellRefs.isEmpty()) { outputEmptyCellComment(commentCellRefs.remove()); } return; } // At the end of a row, handle any comments for "missing" rows before us if (this.cellRef == null) { if (type == EmptyCellCommentsCheckType.END_OF_ROW) { while (!commentCellRefs.isEmpty()) { if (commentCellRefs.peek().getRow() == rowNum) { outputEmptyCellComment(commentCellRefs.remove()); } else { return; } } return; } else { throw new IllegalStateException( "Cell ref should be null only if there are only empty cells in the row; rowNum: " + rowNum); } } CellAddress nextCommentCellRef; do { CellAddress cellRef = new CellAddress(this.cellRef); CellAddress peekCellRef = commentCellRefs.peek(); if (type == EmptyCellCommentsCheckType.CELL && cellRef.equals(peekCellRef)) { // remove the comment cell ref from the list if we're about to handle it alongside the cell content commentCellRefs.remove(); return; } else { // fill in any gaps if there are empty cells with comment mixed in with non-empty cells int comparison = peekCellRef.compareTo(cellRef); if (comparison > 0 && type == EmptyCellCommentsCheckType.END_OF_ROW && peekCellRef.getRow() <= rowNum) { nextCommentCellRef = commentCellRefs.remove(); outputEmptyCellComment(nextCommentCellRef); } else if (comparison < 0 && type == EmptyCellCommentsCheckType.CELL && peekCellRef.getRow() <= rowNum) { nextCommentCellRef = commentCellRefs.remove(); outputEmptyCellComment(nextCommentCellRef); } else { nextCommentCellRef = null; } } } while (nextCommentCellRef != null && !commentCellRefs.isEmpty()); } } /** * Output an empty-cell comment. */ private void outputEmptyCellComment(CellAddress cellRef) { XSSFComment comment = comments.findCellComment(cellRef); output.cell(cellRef.formatAsString(), null, comment, nextDataType, formatString); } private enum EmptyCellCommentsCheckType { CELL, END_OF_ROW, END_OF_SHEET_DATA } /** * You need to implement this to handle the results * of the sheet parsing. */ public interface SheetContentsHandler { /** A row with the (zero based) row number has started */ void startRow(int rowNum); /** A row with the (zero based) row number has ended */ void endRow(int rowNum); /** * A cell, with the given formatted value (may be null), * and possibly a comment (may be null), was encountered. * * Sheets that have missing or empty cells may result in * sparse calls to <code>cell</code>. See the code in * <code>src/examples/src/org/apache/poi/xssf/eventusermodel/XLSX2CSV.java</code> * for an example of how to handle this scenario. */ void cell(String cellReference, String formattedValue, XSSFComment comment, xssfDataType nextDataType, String formatString); /** A header or footer has been encountered */ default void headerFooter(String text, boolean isHeader, String tagName) { } /** Signal that the end of a sheet was been reached */ default void endSheet() { } } }