HTML To PDF Converter

HTMLToPDFConverter is able to convert multiple html files to PDF files.  It is easy to use. The program provides you two options. First, you can select html files in your local computer to be converted to PDF files. A file open dialog is shown. It allows you to select html files from your local computer. You will wait for a while to complete the conversion task.

Another option allows you to convert html files on the web to PDF files. You will need to type or paste the address of the html page in to the Address box and click Add to add this address to the conversion list. You can add many html pages as you want. After adding all addresses that you want  to the list, click OK and wait a moment until the conversion task finishes.

Technically, to convert an html file to a PDF file, there are few steps that have to be taken. These steps are:
-After the html file is read, it is cleaned. The Jsoup library is used to clean the html file.
-The cleaned html file is converted to xhtml file by using the Jtidy library.
-The final step is to convert the xhtml file to a PDF file by using XMLWorker library.

HTMLToPDFConverter source code:

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FilenameFilter;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.Scanner;
import javax.swing.JFileChooser;
import javax.swing.filechooser.FileNameExtensionFilter;
import org.jsoup.Jsoup;
import org.w3c.tidy.Tidy;
import com.itextpdf.text.Document;
import com.itextpdf.text.pdf.PdfWriter;
import com.itextpdf.tool.xml.XMLWorkerHelper;
import org.jsoup.Jsoup;
import org.jsoup.safety.Whitelist;
import org.jsoup.select.Elements;
import javax.swing.*;
import java.awt.event.*;
import java.awt.*;

public class HTMLToPDFConverter{
public static void main(String[] args){

System.out.println("........HTML to PDF Converter......");
int ch;
Scanner sc=new Scanner(System.in);
showOptions();
System.out.println("Enter your choice:");
ch=sc.nextInt();
switch(ch){
case 1: selectLocal();break;
case 2: selectWeb();break;
case 3: System.exit(0);
default: System.out.println("Invalid choice");
}



}


public static void selectLocal(){
JFileChooser chooser = new JFileChooser();
FileNameExtensionFilter filter = new FileNameExtensionFilter("HTML", "html", "htm");
chooser.setFileFilter(filter);
chooser.setMultiSelectionEnabled(true);
int returnVal = chooser.showOpenDialog(null);
if(returnVal == JFileChooser.APPROVE_OPTION) {
File[] Files=chooser.getSelectedFiles();
System.out.println("Please wait...");
        for( int i=0;i<Files.length;i++){    
        String address="file:///"+Files[i].toString();
        loadHTML(address);
        convertHTMLToPDF();
        }
System.out.println("Conversion complete");
        }
}
public static void selectWeb(){
new LinksAdd("Add links");

}

//display a window to add links to the list for conversion

static class LinksAdd extends JFrame implements ActionListener{
DefaultListModel listmodel;
JTextField textlink;
JLabel lblwait;

LinksAdd(String title){
Container cont=getContentPane();
cont.setLayout(new BorderLayout());
setTitle(title);
setPreferredSize(new Dimension(600,300));
JLabel lbl=new JLabel("Address:");
textlink=new JTextField(30);
JButton btadd=new JButton("Add");
btadd.addActionListener(this);
JPanel panelnorth=new JPanel();
panelnorth.add(lbl);
panelnorth.add(textlink);
panelnorth.add(btadd);
listmodel=new DefaultListModel();
JList linkslist=new JList(listmodel);
linkslist.setVisibleRowCount(10);
linkslist.setFixedCellWidth(200);
JScrollPane pane=new JScrollPane(linkslist);
JButton btok=new JButton("OK");
lblwait=new JLabel();
JPanel panelsouth=new JPanel();
panelsouth.add(btok);
panelsouth.add(lblwait);
btok.addActionListener(this);
cont.add(panelnorth, BorderLayout.NORTH);
cont.add(pane, BorderLayout.CENTER);
cont.add(panelsouth, BorderLayout.SOUTH);

pack();
setVisible(true);
}

public void actionPerformed(ActionEvent e){
if(e.getActionCommand().equals("Add")){
if(!textlink.getText().equals("")){
listmodel.addElement(textlink.getText());
textlink.setText("");
}

}
else if(e.getActionCommand().equals("OK")){
Thread t=new Thread(){
public void run(){
lblwait.setText("Please wait...");

for(int i=0;i<listmodel.size();i++){
loadHTML(listmodel.getElementAt(i).toString());
convertHTMLToPDF();
}
dispose();
}
};
t.start();


}
}
}

//read, and convert the original html to xhtml file
//by using parse method of Tidy class
public static void loadHTML(String src){
Tidy tidy=new Tidy();
tidy.setMakeClean(true);
tidy.setXHTML(true);
try{

URL url=new URL(src);
File cleanedHTMLFile=cleanHTML(url.openStream());
tidy.parse(new FileInputStream(cleanedHTMLFile),new FileOutputStream("d:/tempfile.xhtml"));
}catch(Exception fnfe){
System.out.println("The file can't be read.");
System.exit(-1);
}
}
//convert the xhtml file to PDF file by using
//the parseXHtml method of the XMLWorkerHelper class
public static void convertHTMLToPDF(){
try{

Document doc=new Document();
PdfWriter pw=PdfWriter.getInstance(doc, new FileOutputStream(System.currentTimeMillis()+".pdf"));
doc.open();
XMLWorkerHelper.getInstance().parseXHtml(pw, doc, new FileInputStream("d:/tempfile.xhtml"));
doc.close();

}catch(Exception e){
System.out.println("Conversion can't be completed.");
System.exit(-1);}
}


public static File cleanHTML(InputStream srcstream){
String htmlfile="d:/cleanedhtml.html";

try{
org.jsoup.nodes.Document doc=Jsoup.parse(srcstream, "UTF-8", "");
Whitelist wlist=Whitelist.relaxed();
wlist.addAttributes(":all","style","href","ftp","http","https","class");
String cleanedBody=Jsoup.clean(doc.toString(),wlist);
Elements ls=doc.select("body");
ls.remove();
cleanedBody="<body>"+cleanedBody+"</body>";
String cleanedHTML=doc.toString().replaceFirst("</html>",cleanedBody+"</html>");
DataOutputStream dos=new DataOutputStream(new FileOutputStream(htmlfile));
dos.writeBytes(cleanedHTML);
dos.flush();
dos.close();

}catch(IOException ie){System.out.println("Unable to process the file");}
return new File(htmlfile);
}

public static void showOptions(){
System.out.println("1. html files from local computer");
System.out.println("2. html files from the web");

}


}