Blacken is a library designed to assist in the creation of Roguelike games. Roguelike games are named after the game "rogue" which actually predated cursor keys on keyboards.
Blacken is primarily designed to assist with classic character-based games. These games consist of a map composed of letters and punctuations, and the player's character is frequently the "@" character.
Blacken is a Java library, so it does require the Java programming language. (That said, there are ways to use other programs within the bounds of Java. For instance, Jython is a Java implementation of Python.)
Even within the bounds of Java, not all Java environments are equal. I have not tested Blacken with Java ME. I have intentions to eventually support the Android platform, it is currently unsupported.
Blacken is known to work reliably with Java SE -- specifically Java SE 7. I currently test using Oracle's Java 7. I do not believe I do anything that would preclude it from working in other Java 7 environments, but such things are possible. (They should be filed as bugs.)
Please note that there is not, nor will there ever be, any attempt to support Java versions which are old or obsolete. We're actively looking forward to some of the features of Java 8 and when it is ready we will be migrating to it.