Resolving the Unable to Delete PDF Issue After Merging with Itext 5 in Java

Описание: Learn how to effectively handle PDF merging and deletion issues when using the Itext 5 library in Java. This guide covers common pitfalls and presents a solution to enable successful file deletion after merging.
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Troubleshooting PDF Deletion Issues After Merging with Itext 5

When working with PDF files in Java, utilizing a library like Itext 5 can facilitate merging and manipulating documents seamlessly. However, you might encounter an unexpected hurdle: being unable to delete the original PDF files after merging them. In this guide, we will discuss the issue and provide a detailed solution to resolve this problem effectively.

The Problem: Unable to Delete PDF Files

After merging PDF files using the Itext 5 library, you may find that the original files cannot be deleted. This is often indicated by output messages such as "DELETE PDF NOK". Even after executing reader.close(), the problem persists, leading to frustration and inefficiencies in your workflow. This issue often arises from how files are managed and handled within the Itext library as well as specific version compatibility with Java.

Sample Code Triggering the Issue

Let’s take a closer look at the code that typically results in this problem:

[[See Video to Reveal this Text or Code Snippet]]

In this example, the PDF concatenation is executed first, followed by attempt to delete the original files.

The Solution: Adjusting File Handling

To resolve this deletion issue, you need to modify the way the PdfReader instances are created. Instead of initializing PdfReader with the file path, use a FileInputStream. This provides the reader with better control over the file's lifecycle, effectively releasing any locks on the file once operations are complete.

Updated Code Snippet

Here’s how you should adjust the pdfConcat2 method to implement this solution:

[[See Video to Reveal this Text or Code Snippet]]

Final Thoughts

By switching to FileInputStream when creating the PdfReader, you eliminate file lock issues and enhance your ability to manage file deletion without errors. This approach has been noted to be particularly effective since Java 9, addressing compatibility issues that may arise with earlier methodologies.

If you implement these changes in your code, you should find that the deletion of the original PDF files post-merging works as intended, allowing for a cleaner and more efficient codebase. Happy coding!