Once you start to explore the PDF file format you will find out something called ‘ReadOnly’ Text Fields. So what exactly are they and how can they be useful within a PDF?
PDF files contain text fields which allow you to enter text into. I am sure that is not a surprise and that they can be ReadOnly, so that a user cannot edit the text field. Because they cannot be altered, they often include the details to display them as an image. This can be helpful in Java because that often means embedded fonts which can be used to generate an exact representation.
But are they really ‘readonly‘?
So a ‘ReadOnly’ text field is not truly Read Only.
Do you have any experience of these?
This post is part of our “Understanding the PDF File Format” series. In each article, we discuss a PDF feature, bug, gotcha or tip. If you wish to learn more about PDF, we have 13 years worth of PDF knowledge and tips, so click here to visit our series index!
Do you need to write or read JPEG in Java?
We have an easy guide on how to write JPEG in Java using ImageIO and JDeli.
You can learn how to read/write most of the image files in ImageIO. However, it gives little control over the process.
JDeli is easy to use and offers complete support, so why not give JDeli a try?