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encryption in java

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The SHA hash functions are a set of cryptographic hash functions designed by the National Security Agency (NSA) and published by the NIST as a U.S. Federal Information Processing Standard. SHA stands for Secure Hash Algorithm. The three SHA algorithms are structured differently and are distinguished as SHA-0 , SHA-1 , and SHA-2 . The SHA-2 family uses an identical algorithm with a variable digest size which is distinguished as SHA-224 , SHA-256 , SHA-384 , and SHA-512 .   SHA-1 : The Secure Hash Algorithm (SHA) was developed by NIST and is specified in the Secure Hash Standard (SHS, FIPS 180). SHA-1 is a revision to this version and was published in 1994. It is also described in the ANSI X9.30 (part 2) standard. SHA-1 produces a 160-bit (20 byte) message digest. Although slower than MD5, this larger digest size makes it stronger against brute force attacks. MD5 : MD5 was developed by Professor Ronald L. Rivest in 1994. Its 128 bit (16 byte) message digest makes it a faster