I completed the TUI structure (textual user interface). I also wrote part of the Huffman compression algorithm, but it's still incomplete.
Now that the TUI is completed, adding new algorithms to it should be quite quick.
I learnt many things about the Java language, which I researched quite a lot. I also learned about two algorithms for building Huffman trees.
There were many difficulties (mainly related to my limited knowledge of Java). The most difficult problem, which I haven't solved yet, is how to compose a long sequence of bits (bit by bit).
I will complete the Huffman compression and decompression algorithm, and I will write unit tests for the Huffman class. If there is time, I'll start implementing another compression algorithm.