The XLS2CSVmra example that uses HSSF was extremely helpful, so I tried to find
something similar for XSSF, but without any luck. So I offer this as a first draft.
It's rudimentary. I don't really trust the parsing of dates and times. It should
use OPCPackage instead of just Package, but that was not in 3.5-beta5. Further
this uses basic java XML calls to get a SAX-based XML reader, not the direct request
to get a Xerces parser shown in the XSSF and SAX (Event API) FromHowTo example.
Anyhow I offer this in the hope that someone will improve it to the point that
it's worth contributing to the POI XSSF examples area. HTH and thanks for POI.
chris...
---
package something.or.other;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintStream;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.apache.log4j.BasicConfigurator;
import org.apache.poi.openxml4j.exceptions.OpenXML4JException;
import org.apache.poi.openxml4j.opc.Package;
import org.apache.poi.ss.usermodel.DateUtil;
import org.apache.poi.xssf.eventusermodel.XSSFReader;
import org.apache.poi.xssf.model.SharedStringsTable;
import org.apache.poi.xssf.usermodel.XSSFRichTextString;
import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
/**
* A rudimentary XLSX -> CSV processor
* based on XLS2CSVmra by Nick Burch from
* package org.apache.poi.hssf.eventusermodel.examples.
* This is an attempt to demonstrate the same thing using XSSF.
*/
public class XLSX2CSV {
/**
* Derived from
http://poi.apache.org/spreadsheet/how-to.html#xssf_sax_api
*/
class MyXSSFSheetHandler extends DefaultHandler {
private SharedStringsTable sharedStringsTable;
/** Destination for data */
private final PrintStream output;
/** Number of columns to read starting with leftmost */
private final int minColumnCount;
// Runtime
SimpleDateFormat simpleDateFormat = new
SimpleDateFormat("M/d/yyyy");
SimpleDateFormat simpleTimeFormat = new SimpleDateFormat("hh:mm:ss
a");
private boolean nextIsBool;
private boolean nextIsDate;
private boolean nextIsDateTime;
private boolean nextIsString;
private boolean nextIsTime;
private int thisColumn = -1;
// The last column printed to the output stream
private int lastColumnNumber = -1;
private StringBuffer contents;
/**
*
* @param sst
* @param cols
* @param target
*/
public MyXSSFSheetHandler(
SharedStringsTable sst,
int cols,
PrintStream target) {
this.sharedStringsTable = sst;
this.minColumnCount = cols;
this.output = target;
this.contents = new StringBuffer();
}
/*
* (non-Javadoc)
* @see
org.xml.sax.helpers.DefaultHandler#startElement(java.lang.String,
java.lang.String, java.lang.String, org.xml.sax.Attributes)
*/
public void startElement(String uri, String localName, String
name,
Attributes attributes) throws SAXException {
// c => cell
if (name.equals("c")) {
// Get the cell reference
String r = attributes.getValue("r");
int firstDigit = -1;
for (int c = 0; c < r.length(); ++c) {
if (Character.isDigit(r.charAt(c))) {
firstDigit = c;
break;
}
}
thisColumn = nameToColumn(r.substring(0,
firstDigit));
// Figure out if the value is an index in the
SST
// or something else.
String cellType = attributes.getValue("t");
nextIsBool = ("b".equals(cellType));
nextIsString = ("s".equals(cellType));
String cellSomething = attributes.getValue("s");
nextIsDate = ("2".equals(cellSomething));
nextIsTime = ("3".equals(cellSomething));
nextIsDateTime = ("4".equals(cellSomething));
}
// Clear contents cache
contents.setLength(0);
}
/*
* (non-Javadoc)
* @see
org.xml.sax.helpers.DefaultHandler#endElement(java.lang.String,
java.lang.String, java.lang.String)
*/
public void endElement(String uri, String localName, String
name)
throws SAXException {
String thisStr = null;
// Process the last contents as required.
// Do now, as characters() may be called more than once
if(nextIsBool) {
char first = contents.charAt(0);
thisStr = first == '0' ? "FALSE" : "TRUE";
nextIsBool = false;
}
else if(nextIsDate) {
// Actually an integer
double daysSince =
Double.parseDouble(contents.toString());
Date d = DateUtil.getJavaDate(daysSince);
thisStr = simpleDateFormat.format(d);
}
else if(nextIsDateTime) {
// Days to left of decimal, seconds (?) to
right of decimal.
Date d =
DateUtil.getJavaDate(Double.parseDouble(contents.toString()));
thisStr = d.toString();
}
else if(nextIsString) {
String sstIndex = contents.toString();
try {
int idx = Integer.parseInt(sstIndex);
thisStr = new
XSSFRichTextString(sharedStringsTable.getEntryAt(idx)).toString();
nextIsString = false;
}
catch (NumberFormatException ex) {
output.println("Pgmr err, lastContents is
not int: " + sstIndex);
}
}
else if(nextIsTime) {
Date d =
DateUtil.getJavaDate(Double.parseDouble(contents.toString()));
thisStr = simpleTimeFormat.format(d);
}
else {
thisStr = contents.toString();
}
// v => contents of a cell
// Output after we've seen the string contents
if(name.equals("v")) {
// Emit commas for any fields that were missing
on this row
if(lastColumnNumber == -1) { lastColumnNumber =
0; }
for (int i = lastColumnNumber; i < thisColumn;
++i)
output.print(',');
// Might be the empty string.
output.print('"' + thisStr + '"');
}
else if(name.equals("row")) {
// Print out any missing commas if needed
if(minColumns > 0) {
// Columns are 0 based
if(lastColumnNumber == -1) {
lastColumnNumber = 0; }
for(int i=lastColumnNumber;
i<(this.minColumnCount); i++) {
output.print(',');
}
}
// We're onto a new row
output.println();
lastColumnNumber = -1;
}
// Update column
if(thisColumn > -1)
lastColumnNumber = thisColumn;
}
public void characters(char[] ch, int start, int length)
throws SAXException {
contents.append(ch, start, length);
}
/**
* Converts an Excel column name like "C" to a zero-based index.
* @param name
* @return Index corresponding to the specified name
*/
private int nameToColumn(String name) {
int column = -1;
for (int i = 0; i < name.length(); ++i) {
int c = name.charAt(i);
column = (column + 1) * 26 + c - 'A';
}
return column;
}
}
///////////////////////////////////////
private Package xlsxPackage;
private int minColumns;
private PrintStream output;
/**
* Creates a new XLSX -> CSV converter
* Should use OPCPackage instead of Package, but the new one
* is not available in Poi 3.5-beta5.
*
* @param pkg The XLSX package to process
* @param output The PrintStream to output the CSV to
* @param minColumns The minimum number of columns to output, or -1 for
no minimum
*/
public XLSX2CSV(Package pkg, PrintStream output, int minColumns) {
this.xlsxPackage = pkg;
this.output = output;
this.minColumns = minColumns;
}
/**
* @param sst
* @param sheetInputStream
*/
public void processSheet(SharedStringsTable sst, InputStream sheetInputStream)
throws IOException, ParserConfigurationException, SAXException {
InputSource sheetSource = new InputSource(sheetInputStream);
SAXParserFactory saxFactory = SAXParserFactory.newInstance();
SAXParser saxParser = saxFactory.newSAXParser();
XMLReader sheetParser = saxParser.getXMLReader();
ContentHandler handler = new MyXSSFSheetHandler(sst,
this.minColumns, this.output);
sheetParser.setContentHandler(handler);
sheetParser.parse(sheetSource);
}
/**
* Initiates the processing of the XLS file to CSV
* @throws OpenXML4JException
*/
public void process()
throws IOException, OpenXML4JException, ParserConfigurationException, SAXException {
XSSFReader xssfReader = new XSSFReader(this.xlsxPackage);
SharedStringsTable sst = xssfReader.getSharedStringsTable();
XSSFReader.SheetIterator iter =
(XSSFReader.SheetIterator)xssfReader.getSheetsData();
int index = 0;
while (iter.hasNext()) {
InputStream stream = iter.next();
String sheetName = iter.getSheetName();
this.output.println(sheetName + " [index=" + index + "]:");
processSheet(sst, stream);
stream.close();
++index;
}
}
public static void main(String[] args) throws Exception {
if(args.length < 1) {
System.err.println("Use:");
System.err.println(" XLSX2CSV <xlsx file> [min
columns]");
System.exit(1);
}
File xlsxFile = new File(args[0]);
if (! xlsxFile.exists()) {
System.err.println("Not found or not a file: " +
xlsxFile.getPath());
System.exit(1);
}
int minColumns = -1;
if(args.length >= 2) {
minColumns = Integer.parseInt(args[1]);
}
// Provide rudimentary configuration for log4j to avoid these
messages:
// log4j:WARN No appenders could be found for logger
(org.openxml4j.opc).
// log4j:WARN Please initialize the log4j system properly.
BasicConfigurator.configure();
FileInputStream fis = new FileInputStream(xlsxFile);
XLSX2CSV xlsx2csv = new XLSX2CSV(Package.open(fis), System.out,
minColumns);
xlsx2csv.process();
fis.close();
}
}
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