com.Ostermiller.util.MD5.bte Maven / Gradle / Ivy
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<%bte.tpl name=pageTitle%>MD5<%/bte.tpl%>
<%bte.tpl name=description%>Generate MD5 hash sums.<%/bte.tpl%>
<%bte.tpl name=keywords%>md5, md5 hash generator, md5 checksum, md5 library, java md5, check sum md5, message digest, fingerprint md5, signature md5, md5 input stream, md5inputstream, md5 output stream, md5outputstream<%/bte.tpl%>
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MD5 is a cryptographic one way hash algorithm. These classes compute MD5 for Java Strings, byte arrays, or streams. MD5 is now considered a weak algorithm. New applications should consider more secure one way hashes.
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Example
System.out.println(
MD5.getHashString(
"Hello World"
)
);
Security Alert
The MD5 class had a bug in version 1.02.23 and earlier that miscalculated MD5 sums for inputs
of certain odd byte lengths. Please consider the implications for your application and
upgrade to the most recent version.
This class takes as input a message of arbitrary length and produces as output
a 128-bit "fingerprint" or "message digest" of the input. It is conjectured that
it is computationally infeasible to produce two messages having the same message
digest, or to produce any message having a given pre-specified target message
digest. The MD5 algorithm is intended for digital signature applications, where
a large file must be "compressed" in a secure manner before being encrypted with
a private (secret) key under a public-key cryptosystem such as RSA.
This class is based on work by Santeri Paavolainen.
and RFC1321. This implementation is several times
faster and much more memory efficient than Santeri's implementation.
Example
// Print the MD5 hash for a line
// read from standard input
MD5InputStream in = new MD5InputStream(System.in);
int b;
while ((b = in.read()) != -1 && b != '\r' && b != '\n');
System.out.println(in.getHashString());
Input Stream
A filtered input stream that computes an MD5 sum for anything read.
Example
// Write out hello world
// and print its MD5 hash
MD5OutputStream out = new MD5OutputStream(System.out);
out.write("Hello World\n".getBytes());
System.out.println(out.getHashString());
Output Stream
A filtered output stream that computes an MD5 sum for anything written.
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<%bte.tpl name=linkMD5%>MD5 Sums
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