com.itextpdf.signatures.PdfSignatureAppearance Maven / Gradle / Ivy
/*
This file is part of the iText (R) project.
Copyright (c) 1998-2023 Apryse Group NV
Authors: Apryse Software.
This program is offered under a commercial and under the AGPL license.
For commercial licensing, contact us at https://itextpdf.com/sales. For AGPL licensing, see below.
AGPL licensing:
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see
* The size of the layer is determined by the rectangle set via
* {@link PdfSignatureAppearance#setPageRect(Rectangle)}
*
* @return layer 0
*/
public PdfFormXObject getLayer0() {
if (n0 == null) {
n0 = new PdfFormXObject(rect);
n0.makeIndirect(document);
}
return n0;
}
/**
* Get Layer 2 of the appearance.
*
*
* The size of the layer is determined by the rectangle set via
* {@link PdfSignatureAppearance#setPageRect(Rectangle)}
*
* @return layer 2
*/
public PdfFormXObject getLayer2() {
if (n2 == null) {
n2 = new PdfFormXObject(rect);
n2.makeIndirect(document);
}
return n2;
}
/**
* Gets the rendering mode for this signature.
*
* @return the rendering mode for this signature
*/
public RenderingMode getRenderingMode() {
return renderingMode;
}
/**
* Sets the rendering mode for this signature.
*
* @param renderingMode the rendering mode
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setRenderingMode(RenderingMode renderingMode) {
this.renderingMode = renderingMode;
return this;
}
/**
* Returns the signing reason.
*
* @return reason for signing
*/
public String getReason() {
return this.reason;
}
/**
* Sets the signing reason.
*
* @param reason signing reason.
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setReason(String reason) {
this.reason = reason;
return this;
}
/**
* Sets the caption for the signing reason.
*
* @param reasonCaption A new signing reason caption
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setReasonCaption(String reasonCaption) {
this.reasonCaption = reasonCaption;
return this;
}
/**
* Returns the signing location.
*
* @return signing location
*/
public String getLocation() {
return this.location;
}
/**
* Sets the signing location.
*
* @param location A new signing location
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setLocation(String location) {
this.location = location;
return this;
}
/**
* Sets the caption for the signing location.
*
* @param locationCaption A new signing location caption
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setLocationCaption(String locationCaption) {
this.locationCaption = locationCaption;
return this;
}
/**
* Returns the signature creator.
*
* @return The signature creator
*/
public String getSignatureCreator(){
return signatureCreator;
}
/**
* Sets the name of the application used to create the signature.
*
* @param signatureCreator A new name of the application signing a document
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setSignatureCreator(String signatureCreator){
this.signatureCreator = signatureCreator;
return this;
}
/**
* Returns the signing contact.
*
* @return The signing contact
*/
public String getContact() {
return this.contact;
}
/**
* Sets the signing contact.
*
* @param contact A new signing contact
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setContact(String contact) {
this.contact = contact;
return this;
}
/**
* Sets the certificate used to provide the text in the appearance.
* This certificate doesn't take part in the actual signing process.
*
* @param signCertificate the certificate
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setCertificate(Certificate signCertificate) {
this.signCertificate = signCertificate;
return this;
}
/**
* Get the signing certificate.
*
* @return the signing certificate
*/
public Certificate getCertificate() {
return signCertificate;
}
/**
* Gets the Image object to render.
*
* @return the image
*/
public ImageData getSignatureGraphic() {
return signatureGraphic;
}
/**
* Sets the Image object to render when Render is set to RenderingMode.GRAPHIC or RenderingMode.GRAPHIC_AND_DESCRIPTION.
*
* @param signatureGraphic image rendered. If null the mode is defaulted to RenderingMode.DESCRIPTION
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setSignatureGraphic(ImageData signatureGraphic) {
this.signatureGraphic = signatureGraphic;
return this;
}
/**
* Indicates that the existing appearances needs to be reused as layer 0.
*
* @param reuseAppearance is an appearances reusing flag value to set
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setReuseAppearance(boolean reuseAppearance) {
this.reuseAppearance = reuseAppearance;
return this;
}
// layer 2
/**
* Gets the background image for the layer 2.
*
* @return the background image for the layer 2
*/
public ImageData getImage() {
return this.image;
}
/**
* Sets the background image for the layer 2.
*
* @param image the background image for the layer 2
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setImage(ImageData image) {
this.image = image;
return this;
}
/**
* Gets the scaling to be applied to the background image.
*
* @return the scaling to be applied to the background image
*/
public float getImageScale() {
return this.imageScale;
}
/**
* Sets the scaling to be applied to the background image. If it's zero the image
* will fully fill the rectangle. If it's less than zero the image will fill the rectangle but
* will keep the proportions. If it's greater than zero that scaling will be applied.
* In any of the cases the image will always be centered. It's zero by default.
*
* @param imageScale the scaling to be applied to the background image
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setImageScale(float imageScale) {
this.imageScale = imageScale;
return this;
}
/**
* Sets the signature text identifying the signer.
*
* @param text the signature text identifying the signer. If null or not set
* a standard description will be used
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setLayer2Text(String text) {
layer2Text = text;
return this;
}
/**
* Gets the signature text identifying the signer if set by setLayer2Text().
*
* @return the signature text identifying the signer
*/
public String getLayer2Text() {
return layer2Text;
}
/**
* Gets the n2 and n4 layer font.
*
* @return the n2 and n4 layer font
*/
public PdfFont getLayer2Font() {
return this.layer2Font;
}
/**
* Sets the n2 and n4 layer font. If the font size is zero, auto-fit will be used.
*
* @param layer2Font the n2 and n4 font
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setLayer2Font(PdfFont layer2Font) {
this.layer2Font = layer2Font;
return this;
}
/**
* Sets the n2 and n4 layer font size.
*
* @param fontSize font size
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setLayer2FontSize(float fontSize) {
this.layer2FontSize = fontSize;
return this;
}
/**
* Gets the n2 and n4 layer font size.
*
* @return the n2 and n4 layer font size
*/
public float getLayer2FontSize() {
return layer2FontSize;
}
/**
* Sets the n2 and n4 layer font color.
*
* @param color font color
*
* @return this instance to support fluent interface
*/
public PdfSignatureAppearance setLayer2FontColor(Color color) {
this.layer2FontColor = color;
return this;
}
/**
* Gets the n2 and n4 layer font color.
*
* @return the n2 and n4 layer font color
*/
public Color getLayer2FontColor() {
return layer2FontColor;
}
/**
* Gets the visibility status of the signature.
*
* @return the visibility status of the signature
*/
public boolean isInvisible() {
return rect == null || rect.getWidth() == 0 || rect.getHeight() == 0;
}
/**
* Constructs appearance (top-level) for a signature.
*
* @return a top-level signature appearance
* @throws IOException if font cannot be created
* @see Adobe Pdf Digital
* Signature Appearances
*/
protected PdfFormXObject getAppearance() throws IOException {
PdfCanvas canvas;
if (isInvisible()) {
PdfFormXObject appearance = new PdfFormXObject(new Rectangle(0, 0));
appearance.makeIndirect(document);
return appearance;
}
if (n0 == null && !reuseAppearance) {
createBlankN0();
}
if (n2 == null) {
n2 = new PdfFormXObject(rect);
n2.makeIndirect(document);
canvas = new PdfCanvas(n2, document);
int rotation = document.getPage(page).getRotation();
if (rotation == 90) {
canvas.concatMatrix(0, 1, -1, 0, rect.getWidth(), 0);
} else if (rotation == 180) {
canvas.concatMatrix(-1, 0, 0, -1, rect.getWidth(), rect.getHeight());
} else if (rotation == 270) {
canvas.concatMatrix(0, -1, 1, 0, 0, rect.getHeight());
}
Rectangle rotatedRect = rotateRectangle(this.rect, document.getPage(page).getRotation());
String text = layer2Text;
if (null == text) {
text = generateLayer2Text();
}
if (image != null) {
if (imageScale == 0) {
canvas = new PdfCanvas(n2, document);
canvas.addImageWithTransformationMatrix(image, rotatedRect.getWidth(), 0, 0,
rotatedRect.getHeight(), 0, 0);
} else {
float usableScale = imageScale;
if (imageScale < 0) {
usableScale = Math.min(rotatedRect.getWidth() / image.getWidth(),
rotatedRect.getHeight() / image.getHeight());
}
float w = image.getWidth() * usableScale;
float h = image.getHeight() * usableScale;
float x = (rotatedRect.getWidth() - w) / 2;
float y = (rotatedRect.getHeight() - h) / 2;
canvas = new PdfCanvas(n2, document);
canvas.addImageWithTransformationMatrix(image, w, 0, 0, h, x, y);
}
}
PdfFont font;
if (layer2Font == null) {
font = PdfFontFactory.createFont();
} else {
font = layer2Font;
}
Rectangle dataRect = null;
Rectangle signatureRect = null;
if (renderingMode == RenderingMode.NAME_AND_DESCRIPTION ||
renderingMode == RenderingMode.GRAPHIC_AND_DESCRIPTION && this.signatureGraphic != null) {
if (rotatedRect.getHeight() > rotatedRect.getWidth()) {
signatureRect = new Rectangle(
MARGIN,
rotatedRect.getHeight() / 2,
rotatedRect.getWidth() - 2 * MARGIN,
rotatedRect.getHeight() / 2);
dataRect = new Rectangle(
MARGIN,
MARGIN,
rotatedRect.getWidth() - 2 * MARGIN,
rotatedRect.getHeight() / 2 - 2 * MARGIN);
} else {
// origin is the bottom-left
signatureRect = new Rectangle(
MARGIN,
MARGIN,
rotatedRect.getWidth() / 2 - 2 * MARGIN,
rotatedRect.getHeight() - 2 * MARGIN);
dataRect = new Rectangle(
rotatedRect.getWidth() / 2 + MARGIN / 2,
MARGIN,
rotatedRect.getWidth() / 2 - MARGIN,
rotatedRect.getHeight() - 2 * MARGIN);
}
} else if (renderingMode == RenderingMode.GRAPHIC) {
if (signatureGraphic == null) {
throw new IllegalStateException("A signature image must be present when rendering mode is graphic. Use setSignatureGraphic()");
}
signatureRect = new Rectangle(
MARGIN,
MARGIN,
rotatedRect.getWidth() - 2 * MARGIN, // take all space available
rotatedRect.getHeight() - 2 * MARGIN);
} else {
dataRect = new Rectangle(
MARGIN,
MARGIN,
rotatedRect.getWidth() - 2 * MARGIN,
rotatedRect.getHeight() * (1 - TOP_SECTION) - 2 * MARGIN);
}
switch (renderingMode) {
case NAME_AND_DESCRIPTION:
String signedBy =
CertificateInfo.getSubjectFields((X509Certificate) signCertificate).getField("CN");
if (signedBy == null) {
signedBy = CertificateInfo.getSubjectFields((X509Certificate) signCertificate).getField("E");
}
if (signedBy == null) {
signedBy = "";
}
addTextToCanvas(signedBy, font, signatureRect);
break;
case GRAPHIC_AND_DESCRIPTION: {
if (signatureGraphic == null) {
throw new IllegalStateException("A signature image must be present when rendering mode is graphic and description. Use setSignatureGraphic()");
}
float imgWidth = signatureGraphic.getWidth();
if (imgWidth == 0) {
imgWidth = signatureRect.getWidth();
}
float imgHeight = signatureGraphic.getHeight();
if (imgHeight == 0) {
imgHeight = signatureRect.getHeight();
}
float multiplierH = signatureRect.getWidth() / signatureGraphic.getWidth();
float multiplierW = signatureRect.getHeight() / signatureGraphic.getHeight();
float multiplier = Math.min(multiplierH, multiplierW);
imgWidth *= multiplier;
imgHeight *= multiplier;
float x = signatureRect.getRight() - imgWidth;
float y = signatureRect.getBottom() + (signatureRect.getHeight() - imgHeight) / 2;
canvas = new PdfCanvas(n2, document);
canvas.addImageWithTransformationMatrix(signatureGraphic, imgWidth, 0, 0, imgHeight, x, y);
break;
}
case GRAPHIC:
float imgWidth = signatureGraphic.getWidth();
if (imgWidth == 0) {
imgWidth = signatureRect.getWidth();
}
float imgHeight = signatureGraphic.getHeight();
if (imgHeight == 0) {
imgHeight = signatureRect.getHeight();
}
float multiplierH = signatureRect.getWidth() / signatureGraphic.getWidth();
float multiplierW = signatureRect.getHeight() / signatureGraphic.getHeight();
float multiplier = Math.min(multiplierH, multiplierW);
imgWidth *= multiplier;
imgHeight *= multiplier;
float x = signatureRect.getLeft() + (signatureRect.getWidth() - imgWidth) / 2;
float y = signatureRect.getBottom() + (signatureRect.getHeight() - imgHeight) / 2;
canvas = new PdfCanvas(n2, document);
canvas.addImageWithTransformationMatrix(signatureGraphic, imgWidth, 0, 0, imgHeight, x, y);
break;
}
if (renderingMode != RenderingMode.GRAPHIC) {
addTextToCanvas(text, font, dataRect);
}
}
Rectangle rotated = new Rectangle(rect);
if (topLayer == null) {
topLayer = new PdfFormXObject(rotated);
topLayer.makeIndirect(document);
if (reuseAppearance) {
PdfAcroForm acroForm = PdfAcroForm.getAcroForm(document, true);
PdfFormField field = acroForm.getField(fieldName);
PdfStream stream = field.getWidgets().get(0).getAppearanceDictionary().getAsStream(PdfName.N);
PdfFormXObject xobj = new PdfFormXObject(stream);
if (stream != null) {
topLayer.getResources().addForm(xobj, new PdfName("n0"));
PdfCanvas canvas1 = new PdfCanvas(topLayer, document);
canvas1.addXObjectWithTransformationMatrix(xobj, 1, 0, 0, 1, 0, 0);
} else {
reuseAppearance = false;
if (n0 == null) {
createBlankN0();
}
}
}
if (!reuseAppearance) {
topLayer.getResources().addForm(n0, new PdfName("n0"));
PdfCanvas canvas1 = new PdfCanvas(topLayer, document);
canvas1.addXObjectWithTransformationMatrix(n0, 1, 0, 0, 1, 0, 0);
}
topLayer.getResources().addForm(n2, new PdfName("n2"));
PdfCanvas canvas1 = new PdfCanvas(topLayer, document);
canvas1.addXObjectWithTransformationMatrix(n2, 1, 0, 0, 1, 0, 0);
}
PdfFormXObject napp = new PdfFormXObject(rotated);
napp.makeIndirect(document);
napp.getResources().addForm(topLayer, new PdfName("FRM"));
canvas = new PdfCanvas(napp, document);
canvas.addXObjectAt(topLayer,
topLayer.getBBox().getAsNumber(0).floatValue(),
topLayer.getBBox().getAsNumber(1).floatValue());
return napp;
}
/**
* Returns the signature date.
*
* @return the signature date
*/
protected java.util.Calendar getSignDate() {
return signDate;
}
/**
* Sets the signature date.
*
* @param signDate A new signature date
*
* @return this instance to support fluent interface
*/
protected PdfSignatureAppearance setSignDate(java.util.Calendar signDate) {
this.signDate = signDate;
return this;
}
/**
* Set the field name of the appearance.
*
* @param fieldName name of the field
*
* @return this instance to support fluent interface
*/
protected PdfSignatureAppearance setFieldName(String fieldName) {
this.fieldName = fieldName;
return this;
}
private static Rectangle rotateRectangle(Rectangle rect, int angle) {
if (0 == (angle / 90) % 2) {
return new Rectangle(rect.getWidth(), rect.getHeight());
} else {
return new Rectangle(rect.getHeight(), rect.getWidth());
}
}
private void createBlankN0() {
n0 = new PdfFormXObject(new Rectangle(100, 100));
n0.makeIndirect(document);
PdfCanvas canvas = new PdfCanvas(n0, document);
canvas.writeLiteral("% DSBlank\n");
}
private void addTextToCanvas(String text, PdfFont font, Rectangle dataRect) {
PdfCanvas canvas;
canvas = new PdfCanvas(n2, document);
Paragraph paragraph = new Paragraph(text).setFont(font).setMargin(0).setMultipliedLeading(0.9f);
Canvas layoutCanvas = new Canvas(canvas, dataRect);
paragraph.setFontColor(layer2FontColor);
if (layer2FontSize == 0) {
applyCopyFittingFontSize(paragraph, dataRect, layoutCanvas.getRenderer());
} else {
paragraph.setFontSize(layer2FontSize);
}
layoutCanvas.add(paragraph);
}
private void applyCopyFittingFontSize(Paragraph paragraph, Rectangle rect, IRenderer parentRenderer) {
IRenderer renderer = paragraph.createRendererSubTree().setParent(parentRenderer);
LayoutContext layoutContext = new LayoutContext(new LayoutArea(1, rect));
float lFontSize = 0.1f, rFontSize = 100;
int numberOfIterations = 15; // 15 iterations with lFontSize = 0.1 and rFontSize = 100 should result in ~0.003 precision
for (int i = 0; i < numberOfIterations; i++) {
float mFontSize = (lFontSize + rFontSize) / 2;
paragraph.setFontSize(mFontSize);
LayoutResult result = renderer.layout(layoutContext);
if (result.getStatus() == LayoutResult.FULL) {
lFontSize = mFontSize;
} else {
rFontSize = mFontSize;
}
}
paragraph.setFontSize(lFontSize);
}
String generateLayer2Text() {
StringBuilder buf = new StringBuilder();
buf.append("Digitally signed by ");
String name = null;
CertificateInfo.X500Name x500name = CertificateInfo.getSubjectFields((X509Certificate)signCertificate);
if (x500name != null) {
name = x500name.getField("CN");
if (name == null) {
name = x500name.getField("E");
}
}
if (name == null) {
name = "";
}
buf.append(name).append('\n');
buf.append("Date: ").append(SignUtils.dateToString(signDate));
if (reason != null) {
buf.append('\n').append(reasonCaption).append(reason);
}
if (location != null) {
buf.append('\n').append(locationCaption).append(location);
}
return buf.toString();
}
/**
* Signature rendering modes.
*/
public enum RenderingMode {
/**
* The rendering mode is just the description.
*/
DESCRIPTION,
/**
* The rendering mode is the name of the signer and the description.
*/
NAME_AND_DESCRIPTION,
/**
* The rendering mode is an image and the description.
*/
GRAPHIC_AND_DESCRIPTION,
/**
* The rendering mode is just an image.
*/
GRAPHIC
}
}