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java.net.malformedURL exception

URL stringfile = getXsl("test.xml");
File originFile = new File(stringfile.getFile());
String xml = null;
ByteArrayOutputStream pdfStream = null;
try {
FileInputStream fis = new FileInputStream(originFile);
int length = fis.available();
byte[] readData = new byte[length];
fis.read(readData);
xml = (new String(readData)).trim();
fis.close();
xml = xml.substring(xml.lastIndexOf("<HttpCommandList>")+17, xml.lastIndexOf("</HttpCommandList>"));
String[] splitxml = xml.split("</HttpCommand>");
for (int i = 0; i < splitxml.length; i++) {
tmpxml = splitxml[i].trim() + "</HttpCommand>";
System.out.println("splitxml:" +tmpxml);
pdfStream = new ByteArrayOutputStream();
pdf = new com.lowagie.text.Document();
PdfWriter.getInstance(pdf, pdfStream);
pdf.open();
URL xslToUse = getXsl("test.xsl");
// Here am using some utility class to transform
// generate the XML needed by iText to generate the PDF using MessageBuffer contents
String iTextXml = XmlUtil.transformXml(tmpxml.toString(), xslToUse).trim();
// generate the PDF document by parsing the specified XML file
XmlParser.parse(pdf, new ByteArrayInputStream(iTextXml.getBytes()));
}
For the above code, during the XmlParser am getting java.net.malformedURL exception : no protocol
Am trying to generate the pdf document by parsing the specified xml file.

We could need the actual xml-file to decide what is missing. I expect, that there is no protocol defined, just like this:
192.168.1.2/ (no protocol)
file://192.168.1.2/ (there is one)
And URL seems to need one.
Also try:
new File("somexsl.xlt").toURI().toURL();
See here and here.
It always helps spoilering the complete stacktrace. No one knows, where the exception actually occured, if you dont post the line numbers.

POI - Excel remains held by some process and cannot be edited

I am using POI to read,edit and write excel files.
My process flow is like write an excel, read it and again write it.
Then if I try to edit the file using normal desktop excel application while my Java app is still running, the excel cannot be saved, it says some process is holding the excel,
I am properly closing all file handles.
Please help and tell me how to fix this issue.
SXSSFWorkbook wb = new SXSSFWorkbook(WINDOW_SIZE);
Sheet sheet = getCurrentSheet();//stores the current sheet in a instance variable
for (int rowNum = 0; rowNum < data.size(); rowNum++) {
if (rowNum > RECORDS_PER_SHEET) {
if (rowNum % (RECORDS_PER_SHEET * numberOfSheets) == 1) {
numberOfSheets++;
setCurrentSheet(wb.getXSSFWorkbook().createSheet());
sheet = getCurrentSheet();
}
}
final Row row = sheet.createRow(effectiveRowCnt);
for (int columnCount = 0; columnCount < data.get(rowNum).size(); columnCount++) {
final Object value = data.get(rowNum).get(columnCount);
final Cell cell = row.createCell(columnCount);
//This method creates the row and cell at the given loc and adds value
createContent(value, cell, effectiveRowCnt, columnCount, false, false);
}
}
public void closeFile(boolean toOpen) {
FileOutputStream out = null;
try {
out = new FileOutputStream(getFileName());
wb.write(out);
}
finally {
try {
if (out != null) {
out.close();
out = null;
if(toOpen){
// Open the file for user with default program
final Desktop dt = Desktop.getDesktop();
dt.open(new File(getFileName()));
}
}
}
}
}

The code looks correct. After out.close();, there shouldn't be any locks left.
Things that could still happen:
You have another Java process (for example hanging in a debugger). Your new process tries to write the file, fails (because of process 1) and in the finally, it tries to open Excel which sees the same problem. Make sure you log all exceptions that happen in wb.write(out);
Note: The code above looks correct in this respect, since it only starts Excel when out != null and that should only be the case when Java could open the file.
Maybe the file wasn't written completely (i.e. there was an exception during write()). Excel tries to open the corrupt file and gives you the wrong error message.
Use a tool like Process Explorer to find out which process keeps a lock on a file.

I tried all the options. After looking thoroughly, it seems the problem is the Event User model.
I am using the below code for reading the data:
final OPCPackage pkg = OPCPackage.open(getFileName());
final XSSFReader r = new XSSFReader(pkg);
final SharedStringsTable sst = r.getSharedStringsTable();
final XMLReader parser = fetchSheetParser(sst);
final Iterator<InputStream> sheets = r.getSheetsData();
while (sheets.hasNext()) {
final InputStream sheet = sheets.next();
final InputSource sheetSource = new InputSource(sheet);
parser.parse(sheetSource);
sheet.close();
}
I assume the excel is for some reason held by this process for some time. If I remove this code and use the below code:
final File file = new File(getFileName());
final FileInputStream fis = new FileInputStream(file);
final XSSFWorkbook xWb = new XSSFWorkbook(fis);
The process works fine an the excel does not remain locked.

I figured it out actually.
A very simple line was required but some some reason it was not explained in the New Halloween Document (http://poi.apache.org/spreadsheet/how-to.html#sxssf)
I checked the Busy Developer's Guide and got the solution.
I needed to add
pkg.close(); //To close the OPCPackage
This added my code works fine with any number of reads and writes on the same excel file.

Exception when attempting to generate variable-page PDF with iText

I'm trying to create an auto-filled PDF of a government payroll form, which involves the possibility of a variable number of pages. I'm currently storing each page as a Map, with the keys being the names of the fields and the values being their contents.
At the moment, I have this code:
in = new FileInputStream(inputPDF);
PdfCopyFields adder = new PdfCopyFields(outStream);
PdfReader reader = null;
PdfStamper stamper = null;
ByteArrayOutputStream baos = null;
for (int pageNum = 0; pageNum < numPages; pageNum++) {
reader = new PdfReader(in);
baos = new ByteArrayOutputStream();
stamper = new PdfStamper(reader, baos);
AcroFields form = stamper.getAcroFields();
Map<String, String> page = pages.get(pageNum);
setFieldsToPage(form, pageNum);
populatePage(form, page, pageNum);
stamper.close();
reader = new PdfReader(baos.toByteArray());
adder.addDocument(reader);
}
The methods called are:
private void populatePage(AcroFields form, Map<String, String> pageMap, int pageNum) throws Exception {
ArrayList<String> fieldNames = new ArrayList<String>();
for (String key : pageMap.keySet()) {
fieldNames.add(key);
}
for (String key : fieldNames) {
form.setField(key + pageNum, pageMap.get(key));
}
}
and
private void setFieldsToPage(AcroFields form, int pageNum) {
ArrayList<String> fieldNames = new ArrayList<String>();
Map<String, AcroFields.Item> fields = form.getFields();
for (String fieldName : fields.keySet()) {
fieldNames.add(fieldName);
}
for (String fieldName : fieldNames) {
form.renameField(fieldName, fieldName + pageNum);
}
}
The issue is that this throws an exception on the second iteration through the loop: at reader = new PdfReader(in); I get the following exception:
java.io.IOException: PDF header signature not found.
What am I doing wrong here, and how do I fix it?
EDIT:
Here is the exception:
java.io.IOException: PDF header signature not found.
at com.lowagie.text.pdf.PRTokeniser.checkPdfHeader(Unknown Source)
at com.lowagie.text.pdf.PdfReader.readPdf(Unknown Source)
at com.lowagie.text.pdf.PdfReader.<init>(Unknown Source)
at com.lowagie.text.pdf.PdfReader.<init>(Unknown Source)
By the way, I'm sorry if the formatting is bad - this is my first time using stackoverflow.

Your issue is that you essentially try to read the same input stream multiple times while it is positioned at its end already after the first time:
in = new FileInputStream(inputPDF);
[...]
for (int pageNum = 0; pageNum < numPages; pageNum++) {
reader = new PdfReader(in);
[...]
}
The whole stream is read in the first iteration; thus, in the second one new PdfReader(in) essentially tries to parse an empty file resulting in your
java.io.IOException: PDF header signature not found
You can fix that by simply constructing the PdfReader with the input file path directly every time:
for (int pageNum = 0; pageNum < numPages; pageNum++) {
reader = new PdfReader(inputPDF);
[...]
}
Two more things, though:
You don't close your PdfReader instances after use. In the most recent iText versions implicit closing of readers has been taken out of the code as it collides with numerous use cases. Thus, after you finished working with a reader (this includes that any stamper etc using that reader also is closed), you should close the reader explicitly.
In general, if you have a PDF already in your file system, opening a PdfReader for it via a FileInputStream is very wasteful resource-wise --- a reader initialized with an input stream first completely reads that stream into memory (byte[]) and then parses the in-memory representation; a reader initialized with a file path directly parses on-disc representation.

The exception tells you that the file you're reading doesn't start with %PDF-.
Write a small example that doesn't involve iText and check the first 5 bytes of the InputStream in and you'll find out what you're doing wrong (we can't tell you unless you show us those 5 bytes).

How to extract images from Thumbs.db in Java?

HI
I read about POI project and tried to extract images from thumbs.db but getting exception in code .. Code os
InputStream stream = new FileInputStream("C:\\Thumbs.db");
POIFSFileSystem fs = new POIFSFileSystem(stream);
DirectoryEntry root = fs.getRoot();
Entry entry = root.getEntry("2");
DocumentInputStream is = fs.createDocumentInputStream(entry.getName());
JPEGImageDecoder decoder = JPEGCodec.createJPEGDecoder(is);
JPEGDecodeParam param = JPEGCodec.getDefaultJPEGEncodeParam(4, JPEGDecodeParam.COLOR_ID_RGBA);
decoder.setJPEGDecodeParam(param);
BufferedImage originalBufferedImage = decoder.decodeAsBufferedImage();
Getting exception as "com.sun.image.codec.jpeg.ImageFormatException: Not a JPEG file: starts with 0x0c 0x00"
What is problem with above case ?
Can you suggest some other way to do above task ?

You need to read the header of the Thumbs.db file before you can start extracting the images. Try with the changes I added below, it should remove the ImageFormatException you are getting.
InputStream stream = new FileInputStream("C:\\Thumbs.db");
POIFSFileSystem fs = new POIFSFileSystem(stream);
DirectoryEntry root = fs.getRoot();
Entry entry = root.getEntry("2");
DocumentInputStream is = fs.createDocumentInputStream(entry.getName());
//Added to read the header lines and fix the ImageFormatException
int header_len = is.read();
for (int i = 1; i < header_len; i++) {
is.read();
}
JPEGImageDecoder decoder = JPEGCodec.createJPEGDecoder(is);
JPEGDecodeParam param = JPEGCodec.getDefaultJPEGEncodeParam(4,JPEGDecodeParam.COLOR_ID_RGBA);
decoder.setJPEGDecodeParam(param);
BufferedImage originalBufferedImage = decoder.decodeAsBufferedImage();
I hope that helps!

Open Microsoft Word in Java

I'm trying to open MS Word 2003 document in java, search for a specified String and replace it with a new String. I use APACHE POI to do that. My code is like the following one:
public void searchAndReplace(String inputFilename, String outputFilename,
HashMap<String, String> replacements) {
File outputFile = null;
File inputFile = null;
FileInputStream fileIStream = null;
FileOutputStream fileOStream = null;
BufferedInputStream bufIStream = null;
BufferedOutputStream bufOStream = null;
POIFSFileSystem fileSystem = null;
HWPFDocument document = null;
Range docRange = null;
Paragraph paragraph = null;
CharacterRun charRun = null;
Set<String> keySet = null;
Iterator<String> keySetIterator = null;
int numParagraphs = 0;
int numCharRuns = 0;
String text = null;
String key = null;
String value = null;
try {
// Create an instance of the POIFSFileSystem class and
// attach it to the Word document using an InputStream.
inputFile = new File(inputFilename);
fileIStream = new FileInputStream(inputFile);
bufIStream = new BufferedInputStream(fileIStream);
fileSystem = new POIFSFileSystem(bufIStream);
document = new HWPFDocument(fileSystem);
docRange = document.getRange();
numParagraphs = docRange.numParagraphs();
keySet = replacements.keySet();
for (int i = 0; i < numParagraphs; i++) {
paragraph = docRange.getParagraph(i);
text = paragraph.text();
numCharRuns = paragraph.numCharacterRuns();
for (int j = 0; j < numCharRuns; j++) {
charRun = paragraph.getCharacterRun(j);
text = charRun.text();
System.out.println("Character Run text: " + text);
keySetIterator = keySet.iterator();
while (keySetIterator.hasNext()) {
key = keySetIterator.next();
if (text.contains(key)) {
value = replacements.get(key);
charRun.replaceText(key, value);
docRange = document.getRange();
paragraph = docRange.getParagraph(i);
charRun = paragraph.getCharacterRun(j);
text = charRun.text();
}
}
}
}
bufIStream.close();
bufIStream = null;
outputFile = new File(outputFilename);
fileOStream = new FileOutputStream(outputFile);
bufOStream = new BufferedOutputStream(fileOStream);
document.write(bufOStream);
} catch (Exception ex) {
System.out.println("Caught an: " + ex.getClass().getName());
System.out.println("Message: " + ex.getMessage());
System.out.println("Stacktrace follows.............");
ex.printStackTrace(System.out);
}
}
I call this function with following arguments:
HashMap<String, String> replacements = new HashMap<String, String>();
replacements.put("AAA", "BBB");
searchAndReplace("C:/Test.doc", "C:/Test1.doc", replacements);
When the Test.doc file contains a simple line like this : "AAA EEE", it works successfully, but when i use a complicated file it will read the content successfully and generate the Test1.doc file but when I try to open it, it will give me the following error:
Word unable to read this document. It may be corrupt.
Try one or more of the following:
* Open and repair the file.
* Open the file with Text Recovery converter.
(C:\Test1.doc)
Please tell me what to do, because I'm a beginner in POI and I have not found a good tutorial for it.

First of all you should be closing your document.
Besides that, what I suggest doing is resaving your original Word document as a Word XML document, then changing the extension manually from .XML to .doc . Then look at the XML of the actual document you're working with and trace the content to make sure you're not accidentally editing hexadecimal values (AAA and EEE could be hex values in other fields).
Without seeing the actual Word document it's hard to say what's going on.
There is not much documentation about POI at all, especially for Word document unfortunately.

I don't know : is its OK to answer myself, but Just to share the knowledge, I'll answer myself.
After navigating the web, the final solution i found is :
The Library called docx4j is very good for dealing with MS docx file, although its documentation is not enough till now and its forum is still in a beginning steps, but overall it help me to do what i need..
Thanks 4 all who help me..

You could try OpenOffice API, but there arent many resources out there to tell you how to use it.

You can also try this one: http://www.dancrintea.ro/doc-to-pdf/

Looks like this could be the issue.