pdfdocument.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

//	[L5] DocListener interface

    /** margin in x direction starting from the left. Will be valid in the next page */
    protected float nextMarginLeft;
    
    /** margin in x direction starting from the right. Will be valid in the next page */
    protected float nextMarginRight;
    
    /** margin in y direction starting from the top. Will be valid in the next page */
    protected float nextMarginTop;
    
    /** margin in y direction starting from the bottom. Will be valid in the next page */
    protected float nextMarginBottom;
    
    /**
     * Sets the margins.
     *
     * @param	marginLeft		the margin on the left
     * @param	marginRight		the margin on the right
     * @param	marginTop		the margin on the top
     * @param	marginBottom	the margin on the bottom
     * @return	a <CODE>boolean</CODE>
     */
    public boolean setMargins(float marginLeft, float marginRight, float marginTop, float marginBottom) {
        if (writer != null && writer.isPaused()) {
            return false;
        }
        nextMarginLeft = marginLeft;
        nextMarginRight = marginRight;
        nextMarginTop = marginTop;
        nextMarginBottom = marginBottom;
        return true;
    }

//	[L6] DocListener interface
    
    /**
     * @see com.lowagie.text.DocListener#setMarginMirroring(boolean)
     */
    public boolean setMarginMirroring(boolean MarginMirroring) {
        if (writer != null && writer.isPaused()) {
            return false;
        }
        return super.setMarginMirroring(MarginMirroring);
    }

//	[L7] DocListener interface
    
    /**
     * Sets the page number.
     *
     * @param	pageN		the new page number
     */ 
    public void setPageCount(int pageN) {
        if (writer != null && writer.isPaused()) {
            return;
        }
        super.setPageCount(pageN);
    }

//	[L8] DocListener interface
    
    /**
     * Sets the page number to 0.
     */ 
    public void resetPageCount() {
        if (writer != null && writer.isPaused()) {
            return;
        }
        super.resetPageCount();
    }

//	[L9] DocListener interface
    
    /**
     * Changes the header of this document.
     *
     * @param header the new header
     */
    public void setHeader(HeaderFooter header) {
        if (writer != null && writer.isPaused()) {
            return;
        }
        super.setHeader(header);
    }

//	[L10] DocListener interface
    
    /**
     * Resets the header of this document.
     */
    public void resetHeader() {
        if (writer != null && writer.isPaused()) {
            return;
        }
        super.resetHeader();
    }

//	[L11] DocListener interface

    /**
     * Changes the footer of this document.
     *
     * @param	footer		the new footer
     */
    public void setFooter(HeaderFooter footer) {
        if (writer != null && writer.isPaused()) {
            return;
        }
        super.setFooter(footer);
    }

//	[L12] DocListener interface
 
    /**
     * Resets the footer of this document.
     */
    public void resetFooter() {
        if (writer != null && writer.isPaused()) {
            return;
        }
        super.resetFooter();
    }
    
// DOCLISTENER METHODS END

    /** Signals that OnOpenDocument should be called. */
    private boolean firstPageEvent = true;
    
    /**
     * Initializes a page.
     * <P>
     * If the footer/header is set, it is printed.
     * @throws DocumentException on error
     */
    private void initPage() throws DocumentException { 
        // the pagenumber is incremented
        pageN++;

        // initialisation of some page objects
        annotationsImp.resetAnnotations();
        pageResources = new PageResources();
        
        writer.resetContent();
        graphics = new PdfContentByte(writer);
        text = new PdfContentByte(writer);
        text.reset();
        text.beginText();
        textEmptySize = text.size();

    	markPoint = 0;
        if (marginMirroring && (getPageNumber() & 1) == 0) {
            marginRight = nextMarginLeft;
            marginLeft = nextMarginRight;
        }
        else {
            marginLeft = nextMarginLeft;
            marginRight = nextMarginRight;
        }
        marginTop = nextMarginTop;
        marginBottom = nextMarginBottom;
        imageEnd = -1;
        indentation.imageIndentRight = 0;
        indentation.imageIndentLeft = 0;
        indentation.indentBottom = 0;
        indentation.indentTop = 0;
        currentHeight = 0;
        
        // backgroundcolors, etc...
        pageSize = nextPageSize;
        thisBoxSize = new HashMap(boxSize);
        if (pageSize.getBackgroundColor() != null
        || pageSize.hasBorders()
        || pageSize.getBorderColor() != null) {
            add(pageSize);
        }

        float oldleading = leading;
        int oldAlignment = alignment;
        // if there is a footer, the footer is added
        doFooter();
        // we move to the left/top position of the page
        text.moveText(left(), top());
        doHeader();
        pageEmpty = true;
        // if there is an image waiting to be drawn, draw it
        try {
            if (imageWait != null) {
                add(imageWait);
                imageWait = null;
            }
        }
        catch(Exception e) {
            throw new ExceptionConverter(e);
        }
        leading = oldleading;
        alignment = oldAlignment;
        carriageReturn();
        
        PdfPageEvent pageEvent = writer.getPageEvent();
        if (pageEvent != null) {
            if (firstPageEvent) {
                pageEvent.onOpenDocument(writer, this);
            }
            pageEvent.onStartPage(writer, this);
        }
        firstPageEvent = false;
    }

    /** The line that is currently being written. */
    private PdfLine line = null;
    /** The lines that are written until now. */
    private ArrayList lines = new ArrayList();
    
    /**
     * Adds the current line to the list of lines and also adds an empty line.
     * @throws DocumentException on error
     */
    private void newLine() throws DocumentException {
        lastElementType = -1;
        carriageReturn();
        if (lines != null && !lines.isEmpty()) {
            lines.add(line);
            currentHeight += line.height();
        }
        line = new PdfLine(indentLeft(), indentRight(), alignment, leading);
    }
    
    /**
     * If the current line is not empty or null, it is added to the arraylist
     * of lines and a new empty line is added.
     * @throws DocumentException on error
     */  
    private void carriageReturn() {
        // the arraylist with lines may not be null
        if (lines == null) {
            lines = new ArrayList();
        }
        // If the current line is not null
        if (line != null) {
            // we check if the end of the page is reached (bugfix by Francois Gravel)
            if (currentHeight + line.height() + leading < indentTop() - indentBottom()) {
                // if so nonempty lines are added and the heigt is augmented
                if (line.size() > 0) {
                    currentHeight += line.height();
                    lines.add(line);
                    pageEmpty = false;
                }
            }
            // if the end of the line is reached, we start a new page
            else {
                newPage();
            }
        }
        if (imageEnd > -1 && currentHeight > imageEnd) {
            imageEnd = -1;
            indentation.imageIndentRight = 0;
            indentation.imageIndentLeft = 0;
        }
        // a new current line is constructed
        line = new PdfLine(indentLeft(), indentRight(), alignment, leading);
    }
    
    /**
     * Gets the current vertical page position.
     * @param ensureNewLine Tells whether a new line shall be enforced. This may cause side effects 
     *   for elements that do not terminate the lines they've started because those lines will get
     *   terminated. 
     * @return The current vertical page position.
     */
    public float getVerticalPosition(boolean ensureNewLine) {
        // ensuring that a new line has been started.
        if (ensureNewLine) {
          ensureNewLine();
        }
        return top() -  currentHeight - indentation.indentTop;
    }

    /** Holds the type of the last element, that has been added to the document. */
    private int lastElementType = -1;
    
    /**
     * Ensures that a new line has been started. 
     */
    private void ensureNewLine() {
      try {
        if ((lastElementType == Element.PHRASE) || 
            (lastElementType == Element.CHUNK)) {
          newLine();
          flushLines();
        }
      } catch (DocumentException ex) {
        throw new ExceptionConverter(ex);
        }
    }
    
    /**
     * Writes all the lines to the text-object.
     *
     * @return the displacement that was caused
     * @throws DocumentException on error
     */ 
    private float flushLines() throws DocumentException {
        // checks if the ArrayList with the lines is not null
        if (lines == null) {
            return 0;
        }
        boolean newline=false;
        // checks if a new Line has to be made.
        if (line != null && line.size() > 0) {
            lines.add(line);
            line = new PdfLine(indentLeft(), indentRight(), alignment, leading);