Upgrading from APDFL 18 to APDFL 21: Where to Start
Estimated Reading Time: 2 MinutesOverview
Upgrading an application from Adobe PDF Library (APDFL) v18 to v21 primarily involves updating build references, packages, and deployment files. Applications using recent v18 releases can generally retain their existing APDFL API calls. The preparation needed depends on your application's interface and runtime.
Use this overview to choose the migration guide for your application.
Why Consider APDFL v21?
APDFL v21 is built on Adobe's v21 core and includes improvements to PDF processing, rendering, fonts, and document conversion. New capabilities include WebToPDF, Vietnamese OCR, and Brotli compression when saving PDFs. Availability depends on the release, interface, and platform; Brotli also requires compatible PDF readers. For more information, refer to the APDFL v21 Release Notes.
Choose Your Migration Guide
| Interface | Main Changes | Guide |
| Adobe C/C++ | Update library names and SDK paths, replace supporting files, and rebuild | Upgrading Adobe C/C++ Applications from APDFL 18 to APDFL 21 |
| .NET | Retarget to .NET 10 and update NuGet packages and native dependencies | Upgrading .NET and .NET Framework Applications from APDFL 18 to APDFL 21 |
| .NET Framework | Continue with .NET Framework 4.7.1 or later; update NuGet packages and review assembly binding settings | Upgrading .NET and .NET Framework Applications from APDFL 18 to APDFL 21 |
| Java | Plan for JDK 17 or later; update the API, JNI, and resources artifacts together. Packages from 21.1.0 use the Datalogics Maven repository | Upgrading Java Applications from APDFL 18 to APDFL 21 |
Plan the Upgrade
- Check your environment. Confirm platform, architecture, runtime, and licensing support for the selected distribution. Do not assume every interface supports the same platforms.
- Update dependencies together. Keep API libraries, native binaries, plug-ins, and resources compatible. Review scripts that reference v18 filenames or directories.
- Confirm licensing. Preserve the appropriate License-Managed or non-License-Managed distribution, and check license-file or server compatibility where applicable.
- Build and verify. Run representative documents after rebuilding. Rendering, font matching, and color conversion results can differ with the newer core.
Is Modern C++ Required?
No. The existing C++ interface, now called Adobe C/C++, remains supported. Adopting the Modern C++ SDK is a separate API port. See [Migrating from Adobe C/C++ to the APDFL Modern C++ SDK](KB-draft-apdfl-21-modern-cpp-vs-adobe-cpp.md).
How to Get Additional Help
Contact Datalogics Tech Support
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