How to read some lines from a text file using java.
hi,
i m new to java and i want to read some lines from a text file based on some string occurrence in the file. This file to be read in steps.
we only want to read the file upto the first Occurrence of "TEXT" string.
How to do it ,,,
Kinldy give the code
Regards,
Sagar
this is the text file
dfgjdjj
sfjhjkd
ghjkdg
hjkdgh TEXT
ikeyt
ujt
jk
tyk TEXT
rukl
r
Hendawy wrote:
Since the word "TEXT" is formed of 4 letters, you would read the text file 4 bytes by four bytes. Wrong on two counts. First, the file may not be encoded 1 byte per character. It could be utf-16 in which case it would be two byte per character. Second, even if it were 1 byte per character, the string "Text" may not start on a 4 byte boundary.
Consider a FileInputStream object "fis" that points to your text file. use fis.read(byte[] array, int offset, int len) to read every four bytes. Convert the "TEXT" String into a byte array "TEXT".getBytes(), and yous the Arrays class to compare the equality of the read bytes with your "TEXT".getBytes()Wrong since it relies on my second point and will fail when fis.read(byte[] array, int offset, int len) does not read 4 bytes (as is no guaranteed to). Check the Javadoc. Also, the file may not be encoded with the default character encoding.
The problem is easily solved by reading a line at a time using a BufferedReader wrapping an InputStreamReader wrapping a FileInputStream and specifying the correct character encoding.
Edited by: sabre150 on Apr 29, 2009 2:13 PM
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