PdfPages is the PDF Pages-object.
*
* The Pages of a document are accessible through a tree of nodes known as the Pages tree.
* This tree defines the ordering of the pages in the document.
* This object is described in the 'Portable Document Format Reference Manual version 1.3'
* section 6.3 (page 71-73)
*
* @see PdfPage
*/
public class PdfPages {
private ArrayList pages = new ArrayList();
private ArrayList parents = new ArrayList();
private int leafSize = 10;
private PdfWriter writer;
private PdfIndirectReference topParent;
// constructors
/**
* Constructs a PdfPages-object.
*/
PdfPages(PdfWriter writer) {
this.writer = writer;
}
void addPage(PdfDictionary page) {
try {
if ((pages.size() % leafSize) == 0)
parents.add(writer.getPdfIndirectReference());
PdfIndirectReference parent = (PdfIndirectReference)parents.get(parents.size() - 1);
page.put(PdfName.PARENT, parent);
PdfIndirectReference current = writer.getCurrentPage();
writer.addToBody(page, current);
pages.add(current);
}
catch (Exception e) {
throw new ExceptionConverter(e);
}
}
PdfIndirectReference addPageRef(PdfIndirectReference pageRef) {
try {
if ((pages.size() % leafSize) == 0)
parents.add(writer.getPdfIndirectReference());
pages.add(pageRef);
return (PdfIndirectReference)parents.get(parents.size() - 1);
}
catch (Exception e) {
throw new ExceptionConverter(e);
}
}
// returns the top parent to include in the catalog
PdfIndirectReference writePageTree() throws IOException {
if (pages.size() == 0)
throw new IOException("The document has no pages.");
int leaf = 1;
ArrayList tParents = parents;
ArrayList tPages = pages;
ArrayList nextParents = new ArrayList();
while (true) {
leaf *= leafSize;
int stdCount = leafSize;
int rightCount = tPages.size() % leafSize;
if (rightCount == 0)
rightCount = leafSize;
for (int p = 0; p < tParents.size(); ++p) {
int count;
int thisLeaf = leaf;
if (p == tParents.size() - 1) {
count = rightCount;
thisLeaf = pages.size() % leaf;
if (thisLeaf == 0)
thisLeaf = leaf;
}
else
count = stdCount;
PdfDictionary top = new PdfDictionary(PdfName.PAGES);
top.put(PdfName.COUNT, new PdfNumber(thisLeaf));
PdfArray kids = new PdfArray();
ArrayList internal = kids.getArrayList();
internal.addAll(tPages.subList(p * stdCount, p * stdCount + count));
top.put(PdfName.KIDS, kids);
if (tParents.size() > 1) {
if ((p % leafSize) == 0)
nextParents.add(writer.getPdfIndirectReference());
top.put(PdfName.PARENT, (PdfIndirectReference)nextParents.get(p / leafSize));
}
writer.addToBody(top, (PdfIndirectReference)tParents.get(p));
}
if (tParents.size() == 1) {
topParent = (PdfIndirectReference)tParents.get(0);
return topParent;
}
tPages = tParents;
tParents = nextParents;
nextParents = new ArrayList();
}
}
PdfIndirectReference getTopParent() {
return topParent;
}
void setLinearMode(PdfIndirectReference topParent) {
if (parents.size() > 1)
throw new RuntimeException("Linear page mode can only be called with a single parent.");
if (topParent != null) {
this.topParent = topParent;
parents.clear();
parents.add(topParent);
}
leafSize = 10000000;
}
void addPage(PdfIndirectReference page) {
pages.add(page);
}
int reorderPages(int order[]) throws DocumentException {
if (order == null)
return pages.size();
if (parents.size() > 1)
throw new DocumentException("Page reordering requires a single parent in the page tree. Call PdfWriter.setLinearMode() after open.");
if (order.length != pages.size())
throw new DocumentException("Page reordering requires an array with the same size as the number of pages.");
int max = pages.size();
boolean temp[] = new boolean[max];
for (int k = 0; k < max; ++k) {
int p = order[k];
if (p < 1 || p > max)
throw new DocumentException("Page reordering requires pages between 1 and " + max + ". Found " + p + ".");
if (temp[p - 1])
throw new DocumentException("Page reordering requires no page repetition. Page " + p + " is repeated.");
temp[p - 1] = true;
}
Object copy[] = pages.toArray();
for (int k = 0; k < max; ++k) {
pages.set(k, copy[order[k] - 1]);
}
return max;
}
}