Rdex for Java

Rdex Screenshot

Rdex Java is available for Rdex support on Mac and Linux (Windows too if you prefer). The feature set and user interface is similar to Rdex 1.5. All Rdex file formats, ASCII, UTF-8 and AES-128 are supported.

Unzip the file, move the folder to a reasonable location on your machine and run Rdex.jar. There is a readme file with installation instructions for Windows, Mac and Linux. I have tested Rdex Java on Win XP, Win 7, Win 10, OS X 10.11.4 and Linux Ubuntu 14.04 and RHEL 5.

Download Rdex Java 2.6.4—released Aug 2020
rdex-java-2-6-4.zip, 107,770 bytes
md5 hash: 30a4de693dc10407569c732da7fffd1a

Brief Instructions

To create a new card, click on the "New" button, press <Ctrl+N> (use ⌘ instead of Ctrl for all shortcuts on the Mac), or select "Card/New Card" from the menu. Just copy <Ctrl+C> and paste <Ctrl+V> text into the card. If you want to make the "List View" function meaningful, use the first line of the card as a title.

To find a card, type the text you want to search for into the Search box and press <Enter>. Search text is not case sensitive. Press <Enter> again to find the next occurrence or <Shift-Enter> to find the previous one. If the Search box is empty, you simply jump to the next (or previous) card. You can also search for the next occurrence of some text by selecting it with the mouse and pressing <Ctrl+F>.

"Card/List View", <Alt+Enter> or <Ctrl+Enter> will list the first line of all cards containing the text in the Search box. "Card/List All Cards", <Ctrl+L> or the clipboard button will list the first line of all cards. Select the desired card by clicking on it or use the arrow keys and press <Enter>. "Card/Copy List" or <Ctrl+Shift+L> will copy the list to the system clipboard.

Double click on a web link or an email address and Rdex will bring up the link in the default browser or bring up the address in the default email client. This behavior can be enabled/disabled in the Options menu.

Wildcards can be used in a search. A single "?" matches any single character, two "??"s will match any two characters and so on. A "*" matches zero or more occurrences of any character up to a limit of 50 characters. "**" will double the limit to 100 characters and so on. (To seach for a literal "?" or "*" use "\?" or "\*" and use "\\" to mach a literal "\".)

You can delete a card by pressing the "Delete" button, pressing <Ctrl+D>, or selecting "Card/Delete Card" from the menu.

To insert a timestamp (date or date and time) into the card select Edit/Add Timestamp or press <Ctrl+T>. The format of the timestamp can be selected from Options/Set Timestamp Format. To convert a section of text to upper case case, select it with the mouse and choose Edit/To Upper Case or press <Ctrl+U>. For lower case choose Edit/To Lower Case or press <Ctrl+W>.

To start a whole new empty cardfile select "File/New Cardfile" from the menu. (Don't confuse "Card/New Card" with "File/New Cardfile." One is a new card within the current cardfile, the other begins a whole new empty cardfile.)

The "Save As" dialog includes an option "Files of type" to select between ASCII and UTF-8 plain text file formats and AES-128 encrypted file format.

For further help select <Help> from the menu or press F1.

File Formats

Two plain text file formats are available in Rdex, ASCII and UTF-8, and one AES-128 encrypted format. (Details of each file format are discussed in the file formats page.)

In ASCII format the data is stored as a simple ASCII file with cards separated by the ASCII "DEL" character "7F" (in hex). You can edit the data file with a text editor if you wish—just be careful of the card separator characters, they will probably display as an empty square.

The UTF-8 format is able to handle all symbols and characters in all writing systems. Characters will not get confused when shared across different computer systems (e.g. Windows and Android). However, Rdex UTF-8 format is not supported by versions of Rdex earlier than 1.5 for Windows or 2.4.7 for Android.


Rdex supports an AES-128 encrypted file format as of version 1.5.5 for Windows, 2.6.2 for Java and 2.4.17 for Android. (Details of the encryption algorithm are discussed in the file formats page.)

A default passphrase option is available. This allows all encrypted files to use the same passphrase stored in the Rdex application data. It is convenient in that encrypted files can be opened without typing in the passphrase. However, it is not very secure. Use it for protecting data files stored in the cloud or backup copies of the data on a flash drive.

For the higest security do not use the default passphrase option. Use an unguessable passphrase specific to the file you are protecting. The level of security is directly related to the length of the passphrase and how easily it is guessed.

Rdex encryption is not intended for high value data such as bank account numbers and sensitive account login credentials. For these you should use a password safe. Keepass is a free and popular password safe. A password safe encrypts each entry separately and only decrypts an entry when it is displayed. Rdex must decrypt the entire file so that the file can be searched. It remains decrypted in the memory while in use.

Set or clear the default passphrase using "Options/Set Default Passphrase." Encrypt a file or change the passphrase using the "Files of type" dropdown box at the bottom of the "File/Save As" dialog. An option to use the default passphrase or type in a specific passphrase is given in the dialog. You can remove encryption by using the "Files of type" dropdown box to select UTF-8 plain text format.

New in Rdex Java 2.6.4—Aug 2020

New in Rdex Java 2.6.3—Jan 2019

New in Rdex Java 2.6.2—May 2018

Source Code

Here is the source code for Rdex Java 2.6.4. I used the Netbeans 8.2 integrated development environment to create it.

Upgrading from a previous version of Rdex Java

Just unzip the download and replace your existing Rdex.jar with the new one. The download contains a readme file with installation instructions for Windows, Mac and Linux.


This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details: www.gnu.org/licenses.