pdfsignatureappearance.java

iText是一个能够快速产生PDF文件的java类库。iText的java类对于那些要产生包含文本

        loc.add(new PdfNumber(0));
        loc.add(new PdfNumber(0));
        reference.put(new PdfName("DigestLocation"), loc);
        reference.put(new PdfName("DigestMethod"), new PdfName("MD5"));
        reference.put(PdfName.DATA, writer.reader.getTrailer().get(PdfName.ROOT));
        PdfArray types = new PdfArray();
        types.add(reference);
        crypto.put(PdfName.REFERENCE, types);
    }
    
    /**
     * Gets the document bytes that are hashable when using external signatures. The general sequence is:
     * preClose(), getRangeStream() and close().
     * <p>
     * @return the document bytes that are hashable
     */    
    public InputStream getRangeStream() {
        return new PdfSignatureAppearance.RangeStream(raf, bout, range);
    }
    
    /**
     * Gets the user made signature dictionary. This is the dictionary at the /V key.
     * @return the user made signature dictionary
     */    
    public com.lowagie.text.pdf.PdfDictionary getCryptoDictionary() {
        return cryptoDictionary;
    }
    
    /**
     * Sets a user made signature dictionary. This is the dictionary at the /V key.
     * @param cryptoDictionary a user made signature dictionary
     */    
    public void setCryptoDictionary(com.lowagie.text.pdf.PdfDictionary cryptoDictionary) {
        this.cryptoDictionary = cryptoDictionary;
    }
    
    /**
     * Gets the <CODE>PdfStamper</CODE> associated with this instance.
     * @return the <CODE>PdfStamper</CODE> associated with this instance
     */    
    public com.lowagie.text.pdf.PdfStamper getStamper() {
        return stamper;
    }
    
    void setStamper(com.lowagie.text.pdf.PdfStamper stamper) {
        this.stamper = stamper;
    }
    
    /**
     * Checks if the document is in the process of closing.
     * @return <CODE>true</CODE> if the document is in the process of closing,
     * <CODE>false</CODE> otherwise
     */    
    public boolean isPreClosed() {
        return preClosed;
    }
    
    /**
     * Gets the instance of the standard signature dictionary. This instance
     * is only available after pre close.
     * <p>
     * The main use is to insert external signatures.
     * @return the instance of the standard signature dictionary
     */    
    public com.lowagie.text.pdf.PdfSigGenericPKCS getSigStandard() {
        return sigStandard;
    }
    
    /**
     * Gets the signing contact.
     * @return the signing contact
     */
    public String getContact() {
        return this.contact;
    }
    
    /**
     * Sets the signing contact.
     * @param contact the signing contact
     */
    public void setContact(String contact) {
        this.contact = contact;
    }
    
    /**
     * Gets the n2 and n4 layer font.
     * @return the n2 and n4 layer font
     */
    public Font 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
     */
    public void setLayer2Font(Font layer2Font) {
        this.layer2Font = layer2Font;
    }
    
    /**
     * Gets the Acrobat 6.0 layer mode.
     * @return the Acrobat 6.0 layer mode
     */
    public boolean isAcro6Layers() {
        return this.acro6Layers;
    }
    
    /**
     * Acrobat 6.0 and higher recomends that only layer n2 and n4 be present. This method sets that mode.
     * @param acro6Layers if <code>true</code> only the layers n2 and n4 will be present
     */
    public void setAcro6Layers(boolean acro6Layers) {
        this.acro6Layers = acro6Layers;
    }
    
    /** Sets the run direction in the n2 and n4 layer. 
     * @param runDirection the run direction
     */    
    public void setRunDirection(int runDirection) {
        if (runDirection < PdfWriter.RUN_DIRECTION_DEFAULT || runDirection > PdfWriter.RUN_DIRECTION_RTL)
            throw new RuntimeException("Invalid run direction: " + runDirection);
        this.runDirection = runDirection;
    }
    
    /** Gets the run direction.
     * @return the run direction
     */    
    public int getRunDirection() {
        return runDirection;
    }
    
    /**
     * Getter for property signatureEvent.
     * @return Value of property signatureEvent.
     */
    public SignatureEvent getSignatureEvent() {
        return this.signatureEvent;
    }
    
    /**
     * Sets the signature event to allow modification of the signature dictionary.
     * @param signatureEvent the signature event
     */
    public void setSignatureEvent(SignatureEvent signatureEvent) {
        this.signatureEvent = signatureEvent;
    }
    
    /**
     * Gets the background image for the layer 2.
     * @return the background image for the layer 2
     */
    public Image getImage() {
        return this.image;
    }
    
    /**
     * Sets the background image for the layer 2.
     * @param image the background image for the layer 2
     */
    public void setImage(Image image) {
        this.image = image;
    }
    
    /**
     * 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
     */
    public void setImageScale(float imageScale) {
        this.imageScale = imageScale;
    }
    
    /**
     * Commands to draw a yellow question mark in a stream content
     */    
    public static final String questionMark = 
        "% DSUnknown\n" +
        "q\n" +
        "1 G\n" +
        "1 g\n" +
        "0.1 0 0 0.1 9 0 cm\n" +
        "0 J 0 j 4 M []0 d\n" +
        "1 i \n" +
        "0 g\n" +
        "313 292 m\n" +
        "313 404 325 453 432 529 c\n" +
        "478 561 504 597 504 645 c\n" +
        "504 736 440 760 391 760 c\n" +
        "286 760 271 681 265 626 c\n" +
        "265 625 l\n" +
        "100 625 l\n" +
        "100 828 253 898 381 898 c\n" +
        "451 898 679 878 679 650 c\n" +
        "679 555 628 499 538 435 c\n" +
        "488 399 467 376 467 292 c\n" +
        "313 292 l\n" +
        "h\n" +
        "308 214 170 -164 re\n" +
        "f\n" +
        "0.44 G\n" +
        "1.2 w\n" +
        "1 1 0.4 rg\n" +
        "287 318 m\n" +
        "287 430 299 479 406 555 c\n" +
        "451 587 478 623 478 671 c\n" +
        "478 762 414 786 365 786 c\n" +
        "260 786 245 707 239 652 c\n" +
        "239 651 l\n" +
        "74 651 l\n" +
        "74 854 227 924 355 924 c\n" +
        "425 924 653 904 653 676 c\n" +
        "653 581 602 525 512 461 c\n" +
        "462 425 441 402 441 318 c\n" +
        "287 318 l\n" +
        "h\n" +
        "282 240 170 -164 re\n" +
        "B\n" +
        "Q\n";
    
    /**
     * Holds value of property contact.
     */
    private String contact;
    
    /**
     * Holds value of property layer2Font.
     */
    private Font layer2Font;
    
    /**
     * Holds value of property layer4Text.
     */
    private String layer4Text;
    
    /**
     * Holds value of property acro6Layers.
     */
    private boolean acro6Layers;
    
    /**
     * Holds value of property runDirection.
     */
    private int runDirection = PdfWriter.RUN_DIRECTION_NO_BIDI;
    
    /**
     * Holds value of property signatureEvent.
     */
    private SignatureEvent signatureEvent;
    
    /**
     * Holds value of property image.
     */
    private Image image;
    
    /**
     * Holds value of property imageScale.
     */
    private float imageScale;
    
    /**
     *
     */    
    private static class RangeStream extends InputStream {
        private byte b[] = new byte[1];
        private RandomAccessFile raf;
        private byte bout[];
        private int range[];
        private int rangePosition = 0;
        
        private RangeStream(RandomAccessFile raf, byte bout[], int range[]) {
            this.raf = raf;
            this.bout = bout;
            this.range = range;
        }
        
        /**
         * @see java.io.InputStream#read()
         */
        public int read() throws IOException {
            int n = read(b);
            if (n != 1)
                return -1;
            return b[0] & 0xff;
        }
        
        /**
         * @see java.io.InputStream#read(byte[], int, int)
         */
        public int read(byte[] b, int off, int len) throws IOException {
            if (b == null) {
                throw new NullPointerException();
            } else if ((off < 0) || (off > b.length) || (len < 0) ||
            ((off + len) > b.length) || ((off + len) < 0)) {
                throw new IndexOutOfBoundsException();
            } else if (len == 0) {
                return 0;
            }
            if (rangePosition >= range[range.length - 2] + range[range.length - 1]) {
                return -1;
            }
            for (int k = 0; k < range.length; k += 2) {
                int start = range[k];
                int end = start + range[k + 1];
                if (rangePosition < start)
                    rangePosition = start;
                if (rangePosition >= start && rangePosition < end) {
                    int lenf = Math.min(len, end - rangePosition);
                    if (raf == null)
                        System.arraycopy(bout, rangePosition, b, off, lenf);
                    else {
                        raf.seek(rangePosition);
                        raf.readFully(b, off, lenf);
                    }
                    rangePosition += lenf;
                    return lenf;
                }
            }
            return -1;
        }
    }
    
    /**
     * An interface to retrieve the signature dictionary for modification.
     */    
    public interface SignatureEvent {
        /**
         * Allows modification of the signature dictionary.
         * @param sig the signature dictionary
         */        
        public void getSignatureDictionary(PdfDictionary sig);
    }

    private int certificationLevel = NOT_CERTIFIED;

    /**
     * Gets the certified status of this document.
     * @return the certified status
     */
    public int getCertificationLevel() {
        return this.certificationLevel;
    }

    /**
     * Sets the document type to certified instead of simply signed.
     * @param certificationLevel the values can be: <code>NOT_CERTIFIED</code>, <code>CERTIFIED_NO_CHANGES_ALLOWED</code>,
     * <code>CERTIFIED_FORM_FILLING</code> and <code>CERTIFIED_FORM_FILLING_AND_ANNOTATIONS</code>
     */
    public void setCertificationLevel(int certificationLevel) {
        this.certificationLevel = certificationLevel;
    }
}