Simple String Compression Functions

Hi all !
I need two simple String compression functions, like
String compress(String what)
and
String decompress(String what)
myString.equals(decompress(compress(myString)))
should result in true.
Primarily I want to encode some plain text Strings so they are not too easy to read, and compression would be a nice feature here.
I already tried the util.zip package, but that one seems to need streams, I simply need Strings.
Any ideas ??
thx
Skippy

It does not do any compression, in fact it does
expansion to better encrypt the string (about 50%).How does that work? You want encryption to
decrease entropy.Why in the world do you say that, pjt33? What a very odd statement indeed. I sure hope you don't work in security, or I do hope you work in security if I'm a bad guy, or a competitor.
Let's say you had a 6-character string you wanted to encrypt.
Well, if you didn't increase the entropy, any 6-character plaintext string would have a 6-character encoded equivalent. And if you decreased entropy (e.g. coding the most commonly used words to shorter strings,) it gets even easier to decrypt.
Presumably there would be no hash collisions, after all, you want this to be reversible.
Hash collisions decrease entropy too, and, by doing so, make it easier to find a plaintext string that happens to hash to a certain value. This is a Bad Thing.
Now, to decode this, the Bad Guy only has to consider the set of 6-character strings and their hash values. You could even precalculate all of the common dictionary words, and everything with common letters and punctuation, making decryption virtually instantaneous. Especially if you had decreased the entropy in the signal, making fewer things I had to try.
But somebody who increased the entropy of their signal by adding random bits and increasing the encrypted size of the message to, say, 64 characters, would make it a lot harder to decrypt.
The ideal encryption system is pure noise; pure randomized entropy. An indecipherable wall of 0 and 1 seemingly generated at random. Statistical methods can't be used against it; nothing can be deciphered from it; it's as decipherable and meaningless as radio hiss. Now that's encryption!

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