How to Add Password Protection to PDF using iText in Java
- By Viral Patel on June 3, 2012
iText is very powerful library. It is used extensively to create PDF files in Java applications. Although not free, iText is the de-fecto Java library for working with PDF files. It has been extensively used in different Java related products for generating and manipulating PDF files.
Let us see how iText can be used to set password protection (encryption) to a PDF file. Also how to read an encrypted PDF file in Java.
For this we are using our Generate PDF in Java using iText tutorial. You might want to have a look into that tutorial to have an overview of iText and its different APIs that can be used for PDF generation.
To set encryption in iText following API can be used.
String USER_PASS = "Hello123"; String OWNER_PASS = "Owner123"; PdfWriter writer = PdfWriter.getInstance(document, file); writer.setEncryption(USER_PASS.getBytes(), OWNER_PASS.getBytes(), PdfWriter.ALLOW_PRINTING, PdfWriter.ENCRYPTION_AES_128);
Thus .setEncryption() method sets password protection to any PDF file.
Before we get started with code, we need few JAR files. iText internally uses bouncycastle.org library to encrypt the PDF files. We will need following JAR files in addition to iText JAR.
- itextpdf-5.2.1.jar
- bcmail-jdk16-1.46.jar
- bcprov-jdk16-1.46.jar
- bctsp-jdk16-1.46.jar
You can download all these JARs along with the demo source code at the end of this tutorial.
Now following is the Java code to Generate a PDF file and set Password protection to it.
package net.viralpatel.pdf;
import java.io.File;
import java.io.FileOutputStream;
import java.io.OutputStream;
import java.util.Date;
import com.itextpdf.text.Document;
import com.itextpdf.text.Paragraph;
import com.itextpdf.text.pdf.PdfWriter;
public class GeneratePDF {
private static String USER_PASS = "Hello123";
private static String OWNER_PASS = "Owner123";
public static void main(String[] args) {
try {
OutputStream file = new FileOutputStream(new File("D:\\Test.pdf"));
Document document = new Document();
PdfWriter writer = PdfWriter.getInstance(document, file);
writer.setEncryption(USER_PASS.getBytes(), OWNER_PASS.getBytes(),
PdfWriter.ALLOW_PRINTING, PdfWriter.ENCRYPTION_AES_128);
document.open();
document.add(new Paragraph("Hello World, iText"));
document.add(new Paragraph(new Date().toString()));
document.close();
file.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
Thus we used the same steps to generate PDF file that we used in previous tutorial. Just added one line writer.setEncryption() to set password to generated PDF.
Note that in setEncryption() method, we passes several arguments. First two parameters are the password values in bytes. We passed Hello123 and Owner123 as password values. Also the next argument is permission you want to give to user. Following are several permission values.
PdfWriter.ALLOW_PRINTING PdfWriter.ALLOW_ASSEMBLY PdfWriter.ALLOW_COPY PdfWriter.ALLOW_DEGRADED_PRINTING PdfWriter.ALLOW_FILL_IN PdfWriter.ALLOW_MODIFY_ANNOTATIONS PdfWriter.ALLOW_MODIFY_CONTENTS PdfWriter.ALLOW_SCREENREADERS
You can provide multiple permissions by ORing different values. For example PdfWriter.ALLOW_PRINTING | PdfWriter.ALLOW_COPY.
The last parameter is the type of encryption you want to use to encrypt PDF. Following are several allowed values.
PdfWriter.ENCRYPTION_AES_128 PdfWriter.ENCRYPTION_AES_256
Download Source Code
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Hi viralpatel,i tried the example but i got the Following Error at RunTime
java.lang.SecurityException: class “org.bouncycastle.asn1.ASN1ObjectIdentifier”‘s signer information does not match signer information of other classes in the same package
at java.lang.ClassLoader.checkCerts(ClassLoader.java:776)
at java.lang.ClassLoader.preDefineClass(ClassLoader.java:488)
at java.lang.ClassLoader.defineClass(ClassLoader.java:615)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:268)
at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
at com.itextpdf.text.pdf.PdfEncryption.(PdfEncryption.java:147)
at com.itextpdf.text.pdf.PdfWriter.setEncryption(PdfWriter.java:2041)
at net.viralpatel.pdf.main(GeneratePDF.java:35)
Hi Venkata, Check the JDK version you using to compile and run this project. I have used JDK 1.6. The bouncycastle library that I used is also for JDK1.6. Download appropriate version and rerun the project.
Hello
You mention in your article that “Although not free, iText is the de-fecto Java library for working with PDF files”. Our company Qoppa Software has been focusing on Java libraries to work with PDF documents for more than 10 years. Our suite of libraries supports most PDF functions including manipulating (pretty much anything), viewing, printing, annotating. For what you’re doing our library jPDFSecure is the library you should be looking at. It can set passwords and permissions on PDF documents. Price starts at $350 for a dual core server. If you have any questions with our libraries, we’re here to answer at support@qoppa.com. Also all our libraries are compatible with JDK 1.4 and higher.
Hi
I tried that above code its showing
But I used bcmail for JDk 1.7 jar file only
Hi, This error comes when classes belonging to the same package are loaded from different JAR files, and those JAR files have signatures signed with different certificates. Check if you have only one version of org.bouncycastle.asn1.ASN1ObjectIdentifier being loaded by checking all JAR files and see if more than one Jar have this class.
Hi,
I am also getting this error. I have checked my jdk version also .It is jdk1.6.24
Also i am using this itextpdf jar only. Kindly tell the way forward
Hoping that you will reply soon on this
I have also face the java.lang.SecurityException: class “org.bouncycastle.asn1.ASN1ObjectIdentifier”‘s signer information does not match signer information of other classes in the same package.
I am able to solve it.
Do not include apacheds-all-1.5.4.jar in your workspace. The code provided by VP contain the above mentioned jar. That is not required.
Jar required are –
* itextpdf-5.2.1.jar
* bcmail-jdk16-1.46.jar
* bcprov-jdk16-1.46.jar
* bctsp-jdk16-1.46.jar
Thnx a lot ……
Dosen’t work for me. When I use these dependencies:
itextpdf-5.2.1.jar
bcmail-jdk16-1.46.jar
bcprov-jdk16-1.46.jar
bctsp-jdk16-1.46.jar
apacheds-all-1.5.4.jar (same without it)
I get this error: com.itextpdf.text.exceptions.InvalidPdfException: class “org.bouncycastle.asn1.ASN1ObjectIdentifier”‘s signer information does not match signer information of other classes in the same package
Have been trying so many different versions of Bouncy Castle now without any luck. What I’m I doing wrong? Btw. I use jdk 6u27
Delete apacheds-all-1.5.4.jar
Hi Viral Patel ,
This is Excellent and simple one . It helped me lot . But i need to deny the user from copy, save , print . what Constant i need to pass to the encrypt Function .
Thanks in advance.
Exception in thread “main” java.lang.NoClassDefFoundError: org/bouncycastle/asn1/DEREncodable
at com.lowagie.text.pdf.PdfEncryption.(Unknown Source)
at com.lowagie.text.pdf.PdfWriter.setEncryption(Unknown Source)
at com.prs.memberonline.ui.CreatePDFDataWithPassword.print(CreatePDFDataWithPassword.java:99)
at com.prs.memberonline.ui.CreatePDFDataWithPassword.main(CreatePDFDataWithPassword.java:469)
i got the above error while running the class. i downloaded jdk1.4 compatable jars and run it but still it is giving error
Please check this SO thread: http://stackoverflow.com/questions/10391271/itext-bouncycastle-classnotfound-org-bouncycastle-asn1-derencodable-and-org-boun.
Hi Viral Patel ,
This is Excellent and very nice post.