Epublib is a java library for reading/writing epub files. It comes with both a viewer and a command-line tool. It’s intended use is both as part of a larger java application and as a command-line tool.
The api is designed to be as simple as possible, while at the same time making complex things possible too.
// read epub EpubReader epubReader = new EpubReader(); Book book = epubReader.readEpub(new FileInputStream("mybook.epub")); // set title book.getMetadata().setTitles(new ArrayList<String>() {{ add("an awesome book");}}); // write epub EpubWriter epubWriter = new EpubWriter(); epubWriter.write(book, new FileOutputStream("mynewbook.epub"));