Lime is a Japanese input method editor (IME) designed to be used from your web browser. IMEs are software applications that facilitate the entry of text, typically in languages where a key-to-character keyboard mapping would be impossible. Users enter keystrokes according to a particular input method in order to specify a sequence of characters in the target language. The IME handles this conversion process and typically provides an interface to ease the process of inputting and manipulating text. The User Guide provides further information on using Lime.

If you regularly enter text in Japanese, chances are you will have an IME installed and configured on your computer. However, from time to time, you may find yourself sitting at a computer other than your own — one without an IME. If you need to enter Japanese text, your options are somewhat limited.

Many of us have devised creative solutions to get around this problem, most revolving around copying and pasting characters from other sources (online dictionaries, search engine results, etc.) in order to build up a string of text, piece by piece. If you have the consent of the owner of the computer, you may chose to install an application such as Glenn Rosenthal's excellent JWPce, a Japanese word processor with a built-in IME that does not depend on operating system support.

Lime is an alternative solution. Lime provides the user with a text entry field and simple IME, allowing text to be entered and edited before being copied to where it is needed. Lime is entirely web-based and does not depend on any operating system or application support, apart from requiring your web browser to be able to simply display text in Japanese.

There are a number of other web-based tools designed to fulfil a similar role, but none aim to be quite so feature-rich and easy to use as Lime. It should be noted, however, that these features come at a cost — Lime depends on a combination of advanced web technologies such as the XMLHttpRequest API and real-time DOM manipulation that are not supported in all web browsers. Effort has been made to ensure Lime functions correctly in the majority of popular, modern browsers. Feel free to try Lime in your web browser of choice, but YMMV. If Lime refuses to work for you, there is a list of alternative tools and services you may find useful in the User Guide.

There are two parts to Lime — the client and the server. The client is the web page you see when you visit the site. Essentially, it's just that — a web page — albeit with a large chunk of JavaScript hidden within the code to allow it to do what it does. When you select the textbox (which is, in fact, a combination of <div>s pretending to be a text box) and press a key, a keyboard handler captures your keystrokes and proceeds to analyse them. It is designed to recognise patterns representing characters in "wāpuro-rōmaji" (an unambiguous romanisation of the Japanese phonetic sounds) and convert them into an appropriate kana glyph.

When a user marks an inputted string as complete, the text is sent to the server to be converted. The server consults a dictionary to see if it can locate an entry matching the submitted text. If a match is found, a list of suggested conversions is returned to the client. The client then selects the most likely conversion and uses it to replace the original text. The additional suggested conversions are held by the client for the user to choose from should the suggestion originally chosen not be the one the user was after.

The dictionary Lime consults to return conversion suggestions is built from data collected from a variety of sources. Having said that, Lime would not have been possible without the efforts of one man, Jim Breen, who is responsible for virtually single-handedly building the largest resource of publicly available Japanese-English material on the Internet.

For the curious, each source used to build the dictionary is listed below, along with a brief description of how it is employed by Lime.

All of this data is available from The Monash Nihongo FTP Archive. Lime aims to comply with the usage requirements of each source. If you have a vested interest in one of the above sources and object to its use in Lime, please make contact so that we may negotiate its removal from the Lime dictionary.

Changes to Lime are listed below.