Searching for strings in a byte array
I want to do some fairly crude processing on data read by an InputStreamReader. I have performance issues with character processing and the text is ASCII, so I am working with bytes.
In this quick'n'dirty processing, I'd like to be able to search for strings in a character array read by the InputStreamReader. Google enticed me with http://www.goodserver.com/imap4-ssdk/apidocs/com/goodserver/util/ByteArrayHelper.html#indexOf%28byte%5b%5c,%20byte%5b%5c%29 but that would require buying into a library with a load of whistles and bells that aren't needed.
Can anyone suggest a more suitable jar I could use for searching for strings in a byte array?
In this quick'n'dirty processing, I'd like to be able to search for strings in a character array read by the InputStreamReader. Google enticed me with http://www.goodserver.com/imap4-ssdk/apidocs/com/goodserver/util/ByteArrayHelper.html#indexOf%28byte%5b%5c,%20byte%5b%5c%29 but that would require buying into a library with a load of whistles and bells that aren't needed.
Can anyone suggest a more suitable jar I could use for searching for strings in a byte array?
> I'd like to be able to search for strings in a character array
does it really decreases performance if u use new String(charArray).indexOf(
does it really decreases performance if u use new String(charArray).indexOf(
My suggestion would be to use the BufferedReader to increase stream performance. Secondly, as far as the algorithm goes, my recommendation depends on the type search you're doing. Which strings are you searching for? Whole words? Partial words? Across line endings or not?
ASKER
> BufferedReader
This code needs to process large text files quickly. I've taken note of the comparisons at: http://www.javaworld.com/jw-11-2000/jw-1117-performance.html and because I don't need characters so I'd rather work with bytes and buffer locally in a byte array read into by InputStreamReader.
Here's the sum total of the processing I need to do:
(1) Junk any UUEncoded blocks
(a) Look for \nbegin
(b) Ignore characters until \nend
(2) Junk any lines which are longer than (say) 512 bytes
(a) Look for \n
(b) If it comes after > 512 bytes
(3) Copy all unjunked text into a temporary file.
The processing in (2) is very simple and I guess I could look for individual bytes for "begin" and "end" to handle (1), but I'd prefer not to write the code, if I can avoid it :-)
This code needs to process large text files quickly. I've taken note of the comparisons at: http://www.javaworld.com/jw-11-2000/jw-1117-performance.html and because I don't need characters so I'd rather work with bytes and buffer locally in a byte array read into by InputStreamReader.
Here's the sum total of the processing I need to do:
(1) Junk any UUEncoded blocks
(a) Look for \nbegin
(b) Ignore characters until \nend
(2) Junk any lines which are longer than (say) 512 bytes
(a) Look for \n
(b) If it comes after > 512 bytes
(3) Copy all unjunked text into a temporary file.
The processing in (2) is very simple and I guess I could look for individual bytes for "begin" and "end" to handle (1), but I'd prefer not to write the code, if I can avoid it :-)
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Thanks, objects. I suspected as much though I had a mental block about using the reader.
java.lang.String source code: http://www.docjar.com/html/api/java/lang/String.java.html