How to read characters from a text file in java program ?

Sir,
I have to read the characters m to z listed in a text file .
I must compare the character read from the file.
And if any of the characters between m to z is matched i have to replace it with a hexadecimal value.
Any help or suggesstions in this regard would be very useful.
Thanking you,
khurram

Hai,
The requirement is like this
There is an input file, the contents of the file are as follows, you can assume any name for the file.
#Character mappings for Japanese Shift-JIS character set
#ASCII character Mapped Shift-JIS character
m 227,128,133 #Half width katakana letter small m
n 227,128,134 #Half width katakana letter small n
o 227,129,129
p 227,129,130
q 227,129,131
r 227,129,132
s 227,129,133
t 227,129,134
u 227,129,135
v 227,129,136
w 227,129,137
x 227,129,138
y 227,129,139
z 227,129,142
The contents of the above file are to be read as input.
On encountering any character between m to z, i have to do a replacement with a hexadecimal code point value for the multibyte representation in the second column in the input file.
I have the code to get the unicode codepoint value from the multibyte representation, but not from a file.
So if you could please tell me how to get the characters in the second column, it would be very useful for me.
The character # is used to represent the beginning of a comment in the input file.
And comment lines are to be ignored while reading the file.
Say i have a string str="message";
then i should replace the m with the unicode code point value.
Thanking you,
khurram

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