Why am I getting this error? I'm trying to extract information from a bank statement PDF and tally different bills for the month. I write the data from a PDF to a text file so I can get specific data from the file (e.g. ASPEN HOME IMPRO, then iterate down to what the dollar amount is, then read that text line to a string)
When the Files.readAllLines(Path.get("bankData").get(0) code is run, I get the error. Any thoughts why? Encoding issue?
Here is the code:
public static void main(String[] args) throws IOException {
File file = new File("C:\\Users\\wmsai\\Desktop\\BankStatement.pdf");
PDFTextStripper stripper = new PDFTextStripper();
BufferedWriter bw = new BufferedWriter(new FileWriter("bankData"));
BufferedReader br = new BufferedReader(new FileReader("bankData"));
String pdfText = stripper.getText(Loader.loadPDF(file)).toUpperCase();
bw.write(pdfText);
bw.flush();
bw.close();
LineNumberReader lineNum = new LineNumberReader(new FileReader("bankData"));
String aspenHomeImpro = "PAYMENT: ACH: ASPEN HOME IMPRO";
String line;
while ((line = lineNum.readLine()) != null) {
if (line.contains(aspenHomeImpro)) {
int lineNumber = lineNum.getLineNumber();
int newLineNumber = lineNumber + 4;
String aspenData = Files.readAllLines(Paths.get("bankData")).get(0); //This is the code with the error
System.out.println(newLineNumber);
break;
} else if (!line.contains(aspenHomeImpro)) {
continue;
}
}
}
So I figured it out. I had to check the properties of the text file in question (I'm using Eclipse) to figure out what the actual encoding of the text file was.
Then, when creating the file in the program, encode the text file to UTF-8 so that Files.readAllLines could read and grab the data I wanted to get.
We are using PKCS7 Signatures and are signing a document on the server using a signature created on the client. We are creating Pdf Objects in memory, and want to switch to a system where we do not need to depend on system memory. Currently, I am saving the PdfSignatureAppearance Object created while generating hash in session,and then using this object from session when I receive a response from client (Signed Hash Content). Could you please help me figure out a way through which I do not need to save the PdfSignatureAppearance object in session and can directly use the Temp File for signing?
First, we generate a hash of file after inserting signature appearance as shown in the code below:
File file = new File("To be signed file location")
char version = '\u0000'
ByteArrayOutputStream out = new ByteArrayOutputStream()
String outputFile = "Signed file name"
FileOutputStream fileOutputStream = new FileOutputStream(outputFile)
PdfReader pdfReader = new PdfReader(new FileInputStream(file.absolutePath))
PdfStamper stamper = new PdfStamper(pdfReader, out, version, true)
PdfFormField pdfFormField = PdfFormField.createSignature(stamper.getWriter())
String signatureName = "Signature1"
pdfFormField.setWidget(new Rectangle((float) 20, (float) 20, (float) 100, (float) 60), (PdfName) null)
pdfFormField.setFlags(4)
pdfFormField.put(PdfName.DA, new PdfString("/Helv 0 Tf 0 g"))
pdfFormField.setFieldName(signatureName)
pdfFormField.setPage(1)
stamper.addAnnotation(pdfFormField, i)
stamper.close()
pdfReader = new PdfReader(out.toByteArray())
stamper = PdfStamper.createSignature(pdfReader, fileOutputStream, version, (File) null, true)
PdfSignatureAppearance appearance = stamper.getSignatureAppearance()
appearance.setLayer2Text("Digitally Signed by Name")
appearance.setImage(Image.getInstance(esignRequestCO.logoLocation))
appearance.setAcro6Layers(true)
Calendar cal = Calendar.getInstance()
cal.setTime(new Date())
cal.add(12, 5)
appearance.setSignDate(cal)
appearance.setVisibleSignature(signatureName)
int contentEstimated = 16384
HashMap<PdfName, Integer> exc = new HashMap()
exc.put(PdfName.CONTENTS, contentEstimated * 2 + 2)
PdfSignature dic = new PdfSignature(PdfName.ADOBE_PPKLITE, PdfName.ADBE_PKCS7_DETACHED)
dic.setReason(appearance.getReason())
dic.setLocation(appearance.getLocation())
dic.setDate(new PdfDate(appearance.getSignDate()))
appearance.setCryptoDictionary(dic)
appearance.preClose(exc)
InputStream inp = appearance.getRangeStream()
byte[] bytes = IOUtils.toByteArray(inp)
String hash = DigestUtils.sha256Hex(bytes)
As soon as we get the signed content, we insert the content in the file using same appearance object as shown below:
int contentEstimated = 16384
PdfSignatureAppearance appearance = "PdfSignatureAppearance object from session generated in previous step"
byte[] p7barray = "signed content here".bytes
byte[] paddedSig = new byte[contentEstimated]
System.arraycopy(p7barray, 0, paddedSig, 0, p7barray.length)
PdfDictionary dic2 = new PdfDictionary()
dic2.put(PdfName.CONTENTS, (new PdfString(paddedSig)).setHexWriting(true))
appearance.close(dic2)
We are in the last steps of evaluating iText7. We use iText 7.1.0 and html2pdf 2.0.0.
What we do: we send a json_encoded collection with pdf-data (which includes html for header, body and footer) to our Java app. There we iterate over the collection, create a byteArrayOutputStream for each pdf-data element and merge them together. We then send the results to a script which echoes it to e.g. a browser. Although the pdf is displayed correctly, we encounter errors while creating it:
com.itextpdf.io.IOException: Error at file pointer 226,416.
...
Caused by: com.itextpdf.io.IOException: xref subsection not found.
... 73 common frames omitted
If we create only one part of the collection, no error is thrown.
Iterate over collection and merge:
#RequestMapping(value = "/pdf", method = RequestMethod.POST, produces = MediaType.APPLICATION_PDF_VALUE)
public byte[] index(#RequestBody PDFDataModelCollection elements, Model model) throws IOException {
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
PdfWriter writer = new PdfWriter(byteArrayOutputStream);
try (PdfDocument resultDoc = new PdfDocument(writer)) {
for (PDFDataModel pdfDataModel : elements.getElements()) {
PdfReader reader = new PdfReader(new ByteArrayInputStream(creationService.createDatasheet(pdfDataModel)));
try (PdfDocument sourceDoc = new PdfDocument(reader)) {
int n = sourceDoc.getNumberOfPages(); //<-- IOException on second iteration
for (int i = 1; i <= n; i++) {
PdfPage page = sourceDoc.getPage(i).copyTo(resultDoc);
resultDoc.addPage(page);
}
}
}
}
return byteArrayOutputStream.toByteArray(); //outputs the final pdf
}
Creation of part:
public byte[] createDatasheet(PDFDataModel pdfDataModel) throws IOException {
PdfWriter writer = new PdfWriter(byteArrayOutputStream);
//Initialize PDF document
PdfDocument pdfDoc = new PdfDocument(writer);
try (
Document document = new Document(pdfDoc)
) {
//header, footer, etc
//body
for (IElement element : HtmlConverter.convertToElements(pdfDataModel.getBody(), this.props)) {
document.add((IBlockElement) element);
}
footer.writeTotalNumberOnPages(pdfDoc);
}
return byteArrayOutputStream.toByteArray();
}
We are grateful for any suggestion.
In createDatasheet you appear to re-use some byteArrayOutputStream without clearing it first.
In the first iteration, therefore, everything works as desired, at the end of createDatasheet you have a single PDF file in it.
In the second iteration, though, you have two PDF files in that byteArrayOutputStream, one after the other. This concatenation does not form a valid single PDF.
Thus, byteArrayOutputStream.toByteArray() returns something broken.
To fix this, either make the byteArrayOutputStream local to createDatasheet and create a new instance every time or alternatively reset byteArrayOutputStream at the start of createDatasheet:
public byte[] createDatasheet(PDFDataModel pdfDataModel) throws IOException {
byteArrayOutputStream.reset();
PdfWriter writer = new PdfWriter(byteArrayOutputStream);
[...]
I have implemented Digital Signature using iTextSharp Dll to sign PDF files with a single signature creating empty signature fields and update the signature field with signed hash working fine. Now, I want to place the same digital signature in every page of pdf. It's my client requirement.
I’m using the following code:
public class MyExternalSignatureContainer : IExternalSignatureContainer
{
private readonly byte[] signedBytes;
public MyExternalSignatureContainer(byte[] signedBytes)
{
this.signedBytes = signedBytes;
}
public byte[] Sign(Stream data)
{
return signedBytes;
}
public void ModifySigningDictionary(PdfDictionary signDic)
{
}
}
Below code used in program
PdfReader reader = new PdfReader(unsignedPdf);
FileStream os = File.OpenWrite(tempPdf);
PdfStamper stamper = PdfStamper.CreateSignature(reader, os, '\0');
PdfSignatureAppearance appearance = stamper.SignatureAppearance;
appearance.Reason = "Reason1";
appearance.Contact = "";
appearance.Location = "Location1";
appearance.Acro6Layers = false;
appearance.Image = null;
appearance.SignatureRenderingMode = PdfSignatureAppearance.RenderingMode.DESCRIPTION;
appearance.SetVisibleSignature(new iTextSharp.text.Rectangle(36, 748, 144, 780), 1, null);
for (int i = 1; i < 8; i++)
{
var signatureField = PdfFormField.CreateSignature(stamper.Writer);
var signatureRect = new Rectangle(200, 200, 100, 100);
signatureField.Put(PdfName.T, new PdfString("ClientSignature_"+i.ToString()));
PdfIndirectReference PRef = stamper.Writer.PdfIndirectReference;
signatureField.Put(PdfName.V, PRef);
signatureField.Put(PdfName.F, new PdfNumber("132"));
signatureField.SetWidget(signatureRect, null);
signatureField.Put(PdfName.SUBTYPE, PdfName.WIDGET);
PdfDictionary xobject1 = new PdfDictionary();
PdfDictionary xobject2 = new PdfDictionary();
xobject1.Put(PdfName.N, appearance.GetAppearance().IndirectReference);
xobject2.Put(PdfName.AP, xobject1);
signatureField.Put(PdfName.AP, xobject1);
signatureField.SetPage();
PdfDictionary xobject3 = new PdfDictionary();
PdfDictionary xobject4 = new PdfDictionary();
xobject4.Put(PdfName.FRM, appearance.GetAppearance().IndirectReference);
xobject3.Put(PdfName.XOBJECT, xobject4);
signatureField.Put(PdfName.DR, xobject3);
stamper.AddAnnotation(signatureField, i);
}
IExternalSignatureContainer external = new ExternalBlankSignatureContainer(PdfName.ADOBE_PPKMS, PdfName.ADBE_PKCS7_DETACHED);
MakeSignature.SignExternalContainer(appearance, external, 8192);
stamper.Close();
byte[] SignedHash = DoEsign(SHA256Managed.Create().ComputeHash(appearance.GetRangeStream());
os.close();
reader.close();
reader = new PdfReader(tempPdf))
os = File.OpenWrite(signedPdf)
IExternalSignatureContainer external1 = new MyExternalSignatureContainer(SignedHash);
MakeSignature.SignDeferred(reader, signatureFieldName, os, external1);
os.close();
reader.close();
Please suggest me to complete the task
To give all signature fields the same single value wrapping the newly created signature container, they must all reference the same indirect object as value. Unfortunately iText creates the indirect object for the signature value only after the application code had the chance to add its additional fields which in turn require a reference to that signature value object. Thus, the application code has to anticipate the object number that indirect object will have.
This anticipation or prediction of the object number is very delicate, it depends on the exact same use case and can also become incorrect as the result of minor changes in the iTextSharp library
To make this easier, the application code should add those signature fields with their signature value references as late as possible, so there are as few other new indirect objects created as possible until iText creates the value indirect object.
As it turns out, the ModifySigningDictionary method of an IExternalSignatureContainer is a good position for that.
As soon as one adds one's code there, another issue pops up: There is no means to set the anticipated object number in a PdfIndirectReference instance externally. One way to get around this is to mimic such a reference using a PdfLiteral. (Well, probably one could also use reflection for this.)
Furthermore it turns out that one best creates the appearance streams to use by all one's additional signature fields before building that PdfLiteral mimicking a PdfIndirectReference as this simplifies the calculation of the object number iText will use for the actual value object.
With this in mind, here a proof-of concept. This proof of concept makes use of an IExternalSignature instance for actually signing. This is not a necessary precondition, one can also use an IExternalSignatureContainer instead with only a few changes, even an ExternalBlankSignatureContainer as in the question to later finalize the signature using MakeSignature.SignDeferred.
So given cipher parameters cp (private key material, e.g. pk.Key for an Org.BouncyCastle.Pkcs.AsymmetricKeyEntry pk) and a certificate chain chain, one would use
PdfReader reader = new PdfReader(SRC);
FileStream os = new FileStream(DEST, FileMode.Create, FileAccess.Write);
PdfStamper stamper = PdfStamper.CreateSignature(reader, os, '\0');
PdfSignatureAppearance appearance = stamper.SignatureAppearance;
appearance.Reason = "Reason1";
appearance.Contact = "";
appearance.Location = "Location1";
appearance.Acro6Layers = false;
appearance.Image = null;
appearance.SignatureRenderingMode = PdfSignatureAppearance.RenderingMode.DESCRIPTION;
appearance.SetVisibleSignature(new iTextSharp.text.Rectangle(10, 10, 100, 100), reader.NumberOfPages, null);
IExternalSignature externalSignature = new PrivateKeySignature(cp, "SHA-256");
AllPagesSignatureContainer allPagesContainer = new AllPagesSignatureContainer(appearance, externalSignature, chain);
MakeSignature.SignExternalContainer(appearance, allPagesContainer, 8192);
with this external signature container class
public class AllPagesSignatureContainer : IExternalSignatureContainer
{
public AllPagesSignatureContainer(PdfSignatureAppearance appearance, IExternalSignature externalSignature, ICollection<X509Certificate> chain)
{
this.appearance = appearance;
this.chain = chain;
this.externalSignature = externalSignature;
}
public void ModifySigningDictionary(PdfDictionary signDic)
{
signDic.Put(PdfName.FILTER, PdfName.ADOBE_PPKMS);
signDic.Put(PdfName.SUBFILTER, PdfName.ADBE_PKCS7_DETACHED);
PdfStamper stamper = appearance.Stamper;
PdfReader reader = stamper.Reader;
PdfDictionary xobject1 = new PdfDictionary();
PdfDictionary xobject2 = new PdfDictionary();
xobject1.Put(PdfName.N, appearance.GetAppearance().IndirectReference);
xobject2.Put(PdfName.AP, xobject1);
PdfIndirectReference PRef = stamper.Writer.PdfIndirectReference;
PdfLiteral PRefLiteral = new PdfLiteral((PRef.Number + 1 + 2*(reader.NumberOfPages - 1)) + " 0 R");
for (int i = 1; i < reader.NumberOfPages; i++)
{
var signatureField = PdfFormField.CreateSignature(stamper.Writer);
signatureField.Put(PdfName.T, new PdfString("ClientSignature_" + i.ToString()));
signatureField.Put(PdfName.V, PRefLiteral);
signatureField.Put(PdfName.F, new PdfNumber("132"));
signatureField.SetWidget(appearance.Rect, null);
signatureField.Put(PdfName.SUBTYPE, PdfName.WIDGET);
signatureField.Put(PdfName.AP, xobject1);
signatureField.SetPage();
Console.WriteLine(signatureField);
stamper.AddAnnotation(signatureField, i);
}
}
public byte[] Sign(Stream data)
{
String hashAlgorithm = externalSignature.GetHashAlgorithm();
PdfPKCS7 sgn = new PdfPKCS7(null, chain, hashAlgorithm, false);
IDigest messageDigest = DigestUtilities.GetDigest(hashAlgorithm);
byte[] hash = DigestAlgorithms.Digest(data, hashAlgorithm);
byte[] sh = sgn.getAuthenticatedAttributeBytes(hash, null, null, CryptoStandard.CMS);
byte[] extSignature = externalSignature.Sign(sh);
sgn.SetExternalDigest(extSignature, null, externalSignature.GetEncryptionAlgorithm());
return sgn.GetEncodedPKCS7(hash, null, null, null, CryptoStandard.CMS);
}
PdfSignatureAppearance appearance;
ICollection<X509Certificate> chain;
IExternalSignature externalSignature;
}
The predicted indirect object number of the signature value in the line
PdfIndirectReference PRef = stamper.Writer.PdfIndirectReference;
PdfLiteral PRefLiteral = new PdfLiteral((PRef.Number + 1 + 2*(reader.NumberOfPages - 1)) + " 0 R");
strictly depends upon the use case being "exactly one signature field per page". For different use cases the estimate the prediction would differ.
I stress this here once again because e.g. the OP of this question did not take this into account when trying "to place multiple signatures on single page".
Another strict requirement for the object number prediction above is that the PdfStamper is created as above, i.e. not in append mode. If the signature is applied as an incremental update, i.e. in append mode, the lines above have to be replaced by
stamper.Writer.AddToBody(new PdfNull(), stamper.Writer.PdfIndirectReference, true);
PdfIndirectReference PRef = stamper.Writer.PdfIndirectReference;
PdfLiteral PRefLiteral = new PdfLiteral((PRef.Number + reader.NumberOfPages) + " 0 R");
This made a difference in the context of this question; the first line, adding an indirect null object to the PDF, is necessary to make sure that in case of PDFs with object streams the object stream object number has already been determined and does not slip between the next objects, resulting in an off-by-one error for our prediction.
Beware: While this procedure creates something which does not violate the letter of the PDF specifications (which only forbid the cases where the same field object is referenced from multiple pages, be it via the same or via distinct widgets), it clearly does violate its intent, its spirit. Thus, this procedure might also become forbidden as part of a Corrigenda document for the specification.
As the picture show , I need to get byte array from ByteRange to do some verify , they are 0 to 840 and 960 to 1200.
I found the similar question : In Itext 7, how to get the range stream to sign a pdf?
iText in its own verification code needs to do the same thing. It does so in its SignatureUtil class. Thus, one can simply borrow from that code, e.g. like this:
try ( PdfReader pdfReader = new PdfReader(SOURCE_PDF);
PdfDocument pdfDocument = new PdfDocument(pdfReader);) {
SignatureUtil signatureUtil = new SignatureUtil(pdfDocument);
for (String name : signatureUtil.getSignatureNames()) {
PdfSignature signature = signatureUtil.getSignature(name);
PdfArray b = signature.getByteRange();
RandomAccessFileOrArray rf = pdfReader.getSafeFile();
try ( InputStream rg = new RASInputStream(new RandomAccessSourceFactory().createRanged(rf.createSourceView(), SignatureUtil.asLongArray(b)));
OutputStream result = TARGET_STREAM_FOR_name_BYTES) {
byte[] buf = new byte[8192];
int rd;
while ((rd = rg.read(buf, 0, buf.length)) > 0) {
result.write(buf, 0, rd);
}
}
}
}
(RetrieveSignedRanges test testExtractSignedBytes)
If you want the byte range as a byte[] in memory, you can use a ByteArrayOutputStream as TARGET_STREAM_FOR_name_BYTES and retrieve the resulting byte array from it.