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Problem in Calculating the Length...

 
Ranet Saed
Greenhorn
Posts: 7
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Hi I need to calculate the Length of a message saved in a text file so
i wrote the following code:
int len;
try{
FileInputStream Message_File=new FileInputStream
("output8.txt");
BufferedReader buff=new BufferedReader(new
InputStreamReader(Message_File));
String Input_Message=new String();
System.out.println("Your input message is as following:");
while((Input_Message=buff.readLine() )!=null){
// Calculating the the length of our message in unit of bits
System.out.println(Input_Message);
len=Input_Message.length();
System.out.println(len);}
{catch......

this will only give me the length of the last line in the Mesage not
the length of all the message ,so when I Put this statement after while
loop :
len=Input_Message.length();
System.out.println(len);
it will give null exeption:
java.lang.NullPointerException
at final_append.CopyBytes.main(CopyBytes.java:19)
Exception in thread "main"
So what i can do???


Reply
 
Keith Lynn
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Instead of simply assigning the new length to the variable len, you need to accumulate those lengths.
 
Justin Fox
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Posts: 802
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i dont know what kinda of value the variable would be, but you could


set up a variable, which i saw you say byte.

so do this in the while loop..

info += len;

so every time it adds the length of input_w/e to info.

hope this helps a lil

-Justin-
 
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