File i/o in java on linux

MarkSlack · 12-23-2007, 08:47 AM

Hi everyone hope you all enjoying some quality home time at the holiday, my question relates to using java on my slackware installation. I have a class that opens a file and reads data from a text file and then inputs that data into an array. However, i have just migrated from windows to linux and i cannot seem to get the file to read due to the incorrect way in which i have named the file and its path. I have a file called data1.txt and its path is /home/progr/data/data1.txt and as you can see from the code below i have used the same path and filename in the file parameter, however, the filename is not recognised on the compile and i am trying to figure out if i have named this correctly or if there are some other issues here which i have not thought about. Any help would be greatly appreciated.

import java.util.*;

public class EasyReader{
public static void main(String[] args){

EasyReader console = new EasyReader();
final int MAX = 100;
int [] values = new int[MAX];
int [] numberValues = new int[10];
int logicalLength;
logicalLength = fillArray(numberValues);

System.out.print(logicalLength);
}// End Main

public static int fillArray(int []numberValues){
EasyReader File23 = new EasyReader("/home/progr/data/data.txt");
int LL = 0;
int xy= File23.readInt();
while (!File23.eof())
{
numberValues[LL] = xy;
LL++;
xy = File23.readInt();
}// End while
File23.Close();
return LL;
}// End
}// End Class

The second part of the question is if i have a comma separated text file that contains multiple ciolumns of data how do i read the data from the file and place the data in a multidemional array ?

Nylex · 12-23-2007, 10:13 AM

In your code, I don't see a constructor that takes a String, but you're using one in your fillArray() method. Could you post the exact compiler error please? Also, put code in [code] tags.

Mara · 12-25-2007, 03:32 PM

Moved: This thread is more suitable in Programming and has been moved accordingly to help your thread/question get the exposure it deserves.

mmattax · 12-25-2007, 08:52 PM

Quote:

Originally Posted by MarkSlack

The second part of the question is if i have a comma separated text file that contains multiple ciolumns of data how do i read the data from the file and place the data in a multidemional array ?

Look at the string tokenizer class, this class is used to break strings into tokens based on a delimiter, in your case, commas

Code:

import java.util.StringTokenzier;

String str = "foo,bar,gork";
StringTokenizer tok = new StringTokenizer(str,",");

while(tok.hasMoreTokens())
{
    System.out.println(tok.nextToken());
}

would print:

foo
bar
gork

you would just need to add logic to place the string into an array instead of printing them, hope this get you on the right path.

MarkSlack · 01-07-2008, 04:57 AM

thank you for your help and pointing me in the right direction, i have rewritten the routine and it works ok