AozoraEpub3-JDK21 Download

Latest: v1.3.6-jdk21 (May 1, 2026) | Release Notes

📦 Windows (ZIP) 🐧 Linux (TAR.GZ) 🍎 macOS (TAR.GZ)

📋 View all releases

---

What’s New in v1.3.6-jdk21

• Full JDK 26 support: Build, full test execution, and GUI startup are all CI-verified on JDK 26 (JApplet removal per JEP 504 was already addressed). The release artifact is built targeting Java 21 (class file version 65), so it runs on any JRE from JDK 21 LTS through JDK 26
• Codebase modernization: SLF4J logging adoption, java.io.File → java.nio.file.Path migration, java.time API, empty-catch audit with intent comments
• Bug fix: dcterms:modified no longer violates EPUB 3.3 spec under non-Gregorian locales (Thai Buddhist, Japanese era, etc.)
• Breaking changes: Public fields like BookInfo switched from Vector to ArrayList. External libraries using AozoraEpub3 must be recompiled (binary incompatibility)

See the release list for past changes.

---

About This Project

This software is a derivative of AozoraEpub3 by hmdev, updated for Java 21–26 compatibility and support for modern operating systems.

It aims to comply with EPUB 3.3 and the Japanese Book Publishing Association (電書協) EPUB 3 Production Guide, validated with epubcheck 5.x.

---

System Requirements

• Java 25 LTS recommended
  • Compatible with Java 21 LTS as well (JDK 26 runtime also verified)
  • Minimum requirement: Java 21 or later
• Windows / macOS / Linux

If you don’t have Java installed, download Eclipse Temurin Java 25 LTS (Java 21 LTS also works).

---

Install Java 25 (Eclipse Temurin)

Windows

1. Visit Adoptium Releases
2. Select JDK 25 → Windows x64 → .MSI
3. Double-click the MSI file and follow the installer
4. Verify in Command Prompt: java -version

macOS

1. Visit Adoptium Releases
2. Select JDK 25 → macOS → .PKG (Intel or Apple Silicon M1/M2)
3. Double-click the PKG file and follow the installer
4. Verify in Terminal: java -version

Linux (Ubuntu/Debian)

1. Visit Adoptium Releases
2. Select JDK 25 → Linux x64 → .TAR.GZ
3. Extract: tar -xzf OpenJDK25U-jdk_x64_linux_hotspot_25_x.tar.gz
4. Verify: ./jdk-25.x.x+yy/bin/java -version or add to PATH

---

Quick Start (Windows)

1. Download the latest ZIP file from Releases
2. Extract to any folder
3. Double-click AozoraEpub3.exe to launch
4. The GUI will open when ready

Note: If double-clicking the JAR file doesn’t work, use the EXE file instead.

---

Installation (macOS / Linux)

1. Download the TAR.GZ file from Releases
2. Extract: tar -xzf AozoraEpub3-*.tar.gz
3. Navigate to the folder and run: ./AozoraEpub3.sh
4. If you get a permission error, first run: chmod +x AozoraEpub3.sh

---

Command Line Usage

For advanced configuration, you can run from the command line:

java -jar AozoraEpub3.jar -of -d out input.txt

To launch the GUI, run without arguments: java -jar AozoraEpub3.jar

See the README for detailed options.

---

Troubleshooting

• Java is not installed — Download Java 25 LTS from Temurin and install (Java 21 or later also works).
• JAR file won’t open on Windows — Use the EXE file, or launch from Command Prompt with java -jar AozoraEpub3.jar.
• Permission denied on Linux/macOS — Run chmod +x AozoraEpub3.sh and try again.
• Other issues — Report on GitHub Issues.

---

Related Resources

• GitHub README — Features & detailed settings
• EPUB 3.3 Guide — Changes from 3.0 and support status
• 日本語 — このページを日本語で表示