text_output/create_interactive_index
In a Textflow define some terms to be indexed and create a sorted index from the indexed terms. For indicating an indexed term in a Textflow use the inline options "matchbox" and "matchbox end" to create a matchbox at the position to which the index entry will refer to. The matchbox name will be similar to the indexed term. Place the Textflow. Then, create the index by collecting all matchboxes. Each index entry will consist of the matchbox name (indexed term) and the respective page number. Provide the page number with a link annotation to jump to the respective page. Matchboxes are used here a second time to indicate the active link area on the page number.
Note that compiling this code with JDK 1.5 will result in a compiler warning "... uses unchecked or unsafe operations ...". The reason is that we prefer JDK 1.4 compatible code over the use of JDK 1.5 generics.
Download Java Code Show Output PDF
* Create interactive index:
* In a Textflow define some terms to be indexed and create a sorted index from
* the indexed terms
*
* For indicating an indexed term in a Textflow use the inline options
* "matchbox" and "matchbox end" to create a matchbox at the position to which
* the index entry will refer to. The matchbox name will be similar to the
* indexed term. Place the Textflow. Then, create the index by collecting all
* matchboxes. Each index entry will consist of the matchbox name (indexed term)
* and the respective page number. Provide the page number with a link
* annotation to jump to the respective page. Matchboxes are used here a
* second time to indicate the active link area on the page number.
*
* Note that compiling this code with JDK 1.5 will result in a compiler warning
* "... uses unchecked or unsafe operations ...". The reason is that we prefer
* JDK 1.4 compatible code over the use of JDK 1.5 generics.
*
* Required software: PDFlib/PDFlib+PDI/PPS 7.0.3
* Required data: none
*/
package com.pdflib.cookbook.pdflib.text_output;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;
import com.pdflib.pdflib;
import com.pdflib.PDFlibException;
public class create_interactive_index
{
public static void main (String argv[])
{
pdflib p = null;
String searchpath = "../input";
String outfile = "create_interactive_index.pdf";
String title = "Create Interactive Index";
/* Required minimum PDFlib version */
final double requiredversion = 703;
final String requiredvstr = "7.0.3";
final double llx = 20, lly = 20, urx = 200, ury = 200;
final int pagewidth = 250, pageheight = 230;
int i, pageno, entryno, tf = -1, idx = -1;
String mname, result;
double mcount, minfo;
/* Option list to indicate the start of a matchbox */
String startopts = "";
/* Option list to indicate the end of a matchbox */
final String endopts = "matchbox=end";
/* Standard option list for adding a Textflow.
* "avoidemptybegin" deletes empty lines at the beginning of a fitbox.
* "charref" enables the substitution of numeric and character entity
* or glyph name references, e.g. of the character reference "­"
* for a soft hyphen.
*/
final String stdopts = "fontname=Helvetica fontsize=12 encoding=unicode " +
"leading=120% charref avoidemptybegin ";
int ntexts = 10;
/* The text array contains pairs of strings. Each first string will be used
* as indexed term, i.e. the text of an index marker.
*/
String texts[] =
{
"Long Distance Glider",
"\nWith this paper rocket you can send all your messages even when " +
"sitting in a hall or in the cinema pretty near the back.\n\n",
"Giant Wing",
"\nAn unbelievable sailplane! It is amazingly robust and can even " +
"do aerobatics. But it best suited to gliding.\n\n",
"Cone Head Rocket",
"\nThis paper arrow can be thrown with big swing. We launched it " +
"from the roof of a hotel. It stayed in the air a long time and " +
"covered a considerable distance.\n\n",
"Super Dart",
"\nThe super dart can fly giant loops with a radius of 4 or 5 " +
"metres and cover very long distances. Its heavy cone point is " +
"slightly bowed upwards to get the lift required for loops.\n\n",
"German Bi-Plane",
"\nBrand-new and ready for take-off. If you have lessons in the " +
"history of aviation you can show your interest by letting it " +
"land on your teacher's desk.\n\n",
};
/* Index entry containing a name and a page number. For sorting the index
* entries a compare method is provided.
*/
class indexEntry implements Comparable {
String name;
int page;
public int compareTo(Object other) {
return name.compareTo(((indexEntry) other).name);
}
};
/* List of all index entries
*
* With JDK 1.5 and newer, you can write:
* List<indexEntry> index = new LinkedList<indexEntry>();
*
* This prevents the "... uses unchecked or unsafe operations ..." compiler
* warning.
*/
List index = new LinkedList();
try {
p = new pdflib();
p.set_parameter("SearchPath", searchpath);
/* This means we must check return values of load_font() etc. */
p.set_parameter("errorpolicy", "return");
/* Check whether the required minimum PDFlib version is available */
double major = p.get_value("major", 0);
double minor = p.get_value("minor", 0);
double revision = p.get_value("revision", 0);
if (major*100 + minor*10 + revision < requiredversion)
throw new Exception("Error: PDFlib " + requiredvstr +
" or above is required");
/* Start the output document */
if (p.begin_document(outfile, "") == -1)
throw new Exception("Error: " + p.get_errmsg());
p.set_info("Creator", "PDFlib Cookbook");
p.set_info("Title", title + " $Revision: 1.2.4.1 $");
/* ----------------------------------------------------------------
* Add the text Textflow and define a matchbox on each indexed term
* ----------------------------------------------------------------
*/
/* Supply the standard options to the Textflow. This has to be done
* only once. Further calls of add_textflow() for this Textflow will use
* these settings by default.
*/
tf = p.add_textflow(-1, "", stdopts);
if (tf == -1)
throw new Exception("Error: " + p.get_errmsg());
/* Loop over all texts. Add each text and define a matchbox on each
* indexed term. The matchbox name is set to the indexed term.
*/
for (i = 0; i < ntexts; i+=2) {
/* Add text and start a matchbox indicating an indexed term.
* Colorize the matchbox rectangle (only for illustration purposes)
*/
startopts = "matchbox={name={" + texts[i] + "} " +
"fillcolor={rgb 0 0.95 0.95}}";
tf = p.add_textflow(tf, texts[i], startopts);
if (tf == -1)
throw new Exception("Error: " + p.get_errmsg());
/* Add text and finish the matchbox */
tf = p.add_textflow(tf, texts[i+1], endopts);
if (tf == -1)
throw new Exception("Error: " + p.get_errmsg());
}
/* --------------------------------------------------------------------
* Place the text and retrieve all matchboxes (indexed terms) to create
* the index entries from
* --------------------------------------------------------------------
*/
/* Initialize the current page number to be output in the index */
pageno = 0;
/* Initialize the number of index entries */
entryno = 0;
/* Loop until all of the text is placed; create new pages as long as
* more text needs to be placed.
*/
do
{
p.begin_page_ext(pagewidth, pageheight, "");
pageno++;
/* Place the text */
result = p.fit_textflow(tf, llx, lly, urx, ury, "");
/* Place a page number at the lower right corner of the page */
p.fit_textline(String.valueOf(pageno), pagewidth - 20, 10,
"fontname=Helvetica encoding=unicode fontsize=12 " +
"fillcolor={rgb 0 0.95 0.95}");
/* Create the index by creating an index entry from each matchbox on
* the page. Create an index entry by retrieving the matchbox name
* as well as the current page number.
*
* (In our solution multiple index entries may refer to the same
* indexed term. An indexer for general use would combine entries
* for the same term into a single index entry with multiple
* page numbers. Implement this by creating a chain of multiple
* matchboxes for each indexed term.)
*/
/* Query the number of matchboxes on the page; the "num" parameter
* is set to 0 and will be ignored
*/
mcount = p.info_matchbox("*", 0, "count");
for (i = 1; i <= mcount; i++)
{
/* Get the matchbox name */
minfo = p.info_matchbox("*", i, "name");
mname = p.get_parameter("string", minfo);
/* Retrieve the name of the matchbox to be used as the indexed
* term and the page number to be used as the page number in the
* index entry
*/
indexEntry newEntry = new indexEntry();
newEntry.name = new String(mname);
newEntry.page = pageno;
index.add(newEntry);
entryno++;
}
p.end_page_ext("");
/* "_boxfull" means we must continue because there is more text;
* "_nextpage" is interpreted as "start new column"
*/
} while (result.equals("_boxfull") || result.equals("_nextpage"));
/* Check for errors */
if (!result.equals("_stop"))
{
/* "_boxempty" happens if the box is very small and doesn't
* hold any text at all.
*/
if (result.equals( "_boxempty"))
throw new Exception ("Error: Textflow box too small");
else
{
/* Any other return value is a user exit caused by
* the "return" option; this requires dedicated code to
* deal with.
*/
throw new Exception ("User return '" + result +
"' found in Textflow");
}
}
p.delete_textflow(tf);
/* -------------------------------------------------------------
* Sort the list of index entries. Convert it to an array first.
* -------------------------------------------------------------
*/
indexEntry sortedIndex[] = new indexEntry[index.size()];
sortedIndex = (indexEntry[]) index.toArray(sortedIndex);
Arrays.sort(sortedIndex);
/* ---------------------------------------------------------------------
* Construct the contents of the index page(s) based on the collected
* pairs containing the indexed term plus the corresponding page number
* ---------------------------------------------------------------------
*/
/* Supply the standard options to the index Textflow. This has to be
* done only once for each Textflow. Further calls of add_textflow() for
* this Textflow will use these settings by default.
*/
idx = p.add_textflow(-1, "", stdopts);
if (idx == -1)
throw new Exception("Error: " + p.get_errmsg());
/* Add the heading "Index" to the index Textflow */
idx = p.add_textflow(idx, "Index\n\n", "");
if (idx == -1)
throw new Exception("Error: " + p.get_errmsg());
/* Add the collected and sorted index entries to the index Textflow */
for (i = 0; i < sortedIndex.length; i++) {
/* Add the indexed term of the index entry */
idx = p.add_textflow(idx, sortedIndex[i].name + " ",
"fillcolor={gray 0}");
if (idx == -1)
throw new Exception("Error: " + p.get_errmsg());
/* Add the page number of the index entry. In addition, define a
* matchbox with a sequence number as the name. This matchbox will
* be used later to define a link annotation on it to jump to the
* respective page.
*/
idx = p.add_textflow(idx, String.valueOf(sortedIndex[i].page),
"fillcolor={rgb 0 0.95 0.95} matchbox={name=" + i + "}");
if (idx == -1)
throw new Exception("Error: " + p.get_errmsg());
idx = p.add_textflow(idx, "\n", endopts);
if (idx == -1)
throw new Exception("Error: " + p.get_errmsg());
}
/* ---------------------------------------------------------------------
* Place the index Textflow with each entry consisting of a text, a page
* number, and a link annotation on the page number
* ---------------------------------------------------------------------
*/
/* Initialize the current number of the index entry */
entryno = 0;
/* Loop until all index entries are placed; create new pages as long as
* more index entries need to be placed
*/
do
{
p.begin_page_ext(pagewidth, pageheight, "");
pageno++;
/* Fit the index Textflow */
result = p.fit_textflow(idx, llx, lly, urx, ury, "");
/* Place a page number */
p.fit_textline(String.valueOf(pageno), pagewidth - 20, 10,
"fontname=Helvetica encoding=unicode fontsize=12 " +
"fillcolor={rgb 0 0.95 0.95}");
/* Collect the index entries by retrieving the number of matchboxes
* on the current page
*/
mcount = p.info_matchbox("*", 1, "count");
for (i = 1; i <= mcount; i++)
{
/* Get the matchbox name which corresponds to the text of the
* index entry
*/
minfo = p.info_matchbox("*", i, "name");
mname = p.get_parameter("string", minfo);
int action = p.create_action("GoTo", "destination={page=" +
(sortedIndex[entryno].page) + "}");
/* With the "GoTo" action, create a Link annotation on the
* matchbox defined above. 0 rectangle coordinates will be
* replaced with matchbox coordinates.
*/
p.create_annotation(0, 0, 0, 0, "Link",
"action={activate " + action + "} linewidth=0 " +
"usematchbox={" + mname + "}");
entryno++;
}
p.end_page_ext("");
} while (result.equals("_boxfull") || result.equals("_nextpage"));
/* Check for errors */
if (!result.equals("_stop"))
{
/* "_boxempty" happens if the box is very small and doesn't
* hold any text at all.
*/
if (result.equals( "_boxempty"))
throw new Exception ("Error: Textflow box too small");
else
{
/* Any other return value is a user exit caused by
* the "return" option; this requires dedicated code to
* deal with.
*/
throw new Exception ("User return '" + result +
"' found in Textflow");
}
}
p.delete_textflow(idx);
p.end_document("");
} catch (PDFlibException e) {
System.err.print("PDFlib exception occurred:\n");
System.err.print("[" + e.get_errnum() + "] " + e.get_apiname() +
": " + e.get_errmsg() + "\n");
} catch (Exception e) {
System.err.println(e.toString());
} finally {
if (p != null) {
p.delete();
}
}
}
}