org.apache.fop.pdf.PDFOutline Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* $Id: PDFOutline.java 1661887 2015-02-24 11:23:44Z ssteiner $ */
package org.apache.fop.pdf;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.List;
import java.util.Set;
/**
* This represents a single Outline object in a PDF, including the root Outlines
* object. Outlines provide the bookmark bar, usually rendered to the right of
* a PDF document in user agents such as Acrobat Reader.
*
* This work was authored by Kelly A. Campbell.
*/
public class PDFOutline extends PDFObject {
/**
* list of sub-entries (outline objects)
*/
private List subentries;
/**
* parent outline object. Root Outlines parent is null
*/
private PDFOutline parent;
private PDFOutline prev;
private PDFOutline next;
private PDFOutline first;
private PDFOutline last;
private int count;
// whether to show this outline item's child outline items
private boolean openItem;
/**
* title to display for the bookmark entry
*/
private String title;
private PDFReference actionRef;
/**
* Create a PDF outline with the title and action.
*
* @param title the title of the outline entry (can only be null for root Outlines obj)
* @param action the action for this outline
* @param openItem indicator of whether child items are visible or not
*/
public PDFOutline(String title, PDFReference action, boolean openItem) {
super();
subentries = new java.util.ArrayList();
count = 0;
parent = null;
prev = null;
next = null;
first = null;
last = null;
this.title = title;
actionRef = action;
this.openItem = openItem;
}
/**
* Set the title of this Outline object.
*
* @param t the title of the outline
*/
public void setTitle(String t) {
title = t;
}
/**
* Add a sub element to this outline.
*
* @param outline a sub outline
*/
public void addOutline(PDFOutline outline) {
if (subentries.size() > 0) {
outline.prev
= (PDFOutline)subentries.get(subentries.size() - 1);
outline.prev.next = outline;
} else {
first = outline;
}
subentries.add(outline);
outline.parent = this;
// note: count is not just the immediate children
incrementCount();
last = outline;
}
/**
* Increment the number of subentries and descendants.
*/
private void incrementCount() {
// count is a total of our immediate subentries
// and all descendent subentries
count++;
if (parent != null) {
parent.incrementCount();
}
}
/**
* {@inheritDoc}
*/
protected byte[] toPDF() {
ByteArrayOutputStream bout = new ByteArrayOutputStream(128);
try {
bout.write(encode("<<"));
if (parent == null) {
// root Outlines object
if (first != null && last != null) {
bout.write(encode(" /First " + first.referencePDF() + "\n"));
bout.write(encode(" /Last " + last.referencePDF() + "\n"));
// no count... we start with the outline completely closed for now
}
} else {
// subentry Outline item object
bout.write(encode(" /Title "));
bout.write(encodeText(this.title));
bout.write(encode("\n"));
bout.write(encode(" /Parent " + parent.referencePDF() + "\n"));
if (prev != null) {
bout.write(encode(" /Prev " + prev.referencePDF() + "\n"));
}
if (next != null) {
bout.write(encode(" /Next " + next.referencePDF() + "\n"));
}
if (first != null && last != null) {
bout.write(encode(" /First " + first.referencePDF() + "\n"));
bout.write(encode(" /Last " + last.referencePDF() + "\n"));
}
if (count > 0) {
bout.write(encode(" /Count " + (openItem ? "" : "-")
+ count + "\n"));
}
if (actionRef != null) {
bout.write(encode(" /A " + actionRef + "\n"));
}
}
bout.write(encode(">>"));
} catch (IOException ioe) {
log.error("Ignored I/O exception", ioe);
}
return bout.toByteArray();
}
@Override
public void getChildren(Set children) {
if (parent != null) {
children.add(parent);
}
if (first != null && last != null) {
children.add(first);
children.add(last);
first.getChildren(children);
last.getChildren(children);
}
if (actionRef != null) {
children.add(actionRef.getObject());
}
}
}