Anyone know how to take info from a txt file and convert it to a char array?

[2potatocakes]

I'm really sorry guys, In my head this seems like the easiest thing in the world to do, but I cannot get it to work?

Can anyone suggest how?

me = noob

[Supamagier]

Do you know how to read the file? if so, just use

Code:

String.toCharArray

if not, google it. no spoon feeding.

[Norm]

Do you want one entry in the array for each character in the file?
What character set is the file in? ASCII or ? ASCII would be the easiest.
Look thru the API doc I/O packages to find an input method that will return a single character. Perhaps some version of read(). Then open the file, read it a character at a time and save the char in the array. Some input methods will "eat" lineend characters and you won't see them. Is that important?

[Nicholas Jordan]

I will gladly spoon feed this:

Use any Reader subclass that has a readLine();

That goes to a String, which is subject to all manner of sane approaches. You just do it one line at a time.

[pawankumarom]

I also want to know how many type very able in java.

[Eranga]

Quote:

Originally Posted by pawankumarom

I also want to know how many type very able in java.

Are you talking about variable types? If so, better to read more about Java basis.

[2potatocakes]

Thanks to all the guys that wrote something constructive on here

But it was my fault for not asking the question correctly. It was more like half of a question. Here's my dilemna:

I have a txt file filled with hundreds and thousands of digits and no spaces.

I can read from the text file no probs and have been using get chars to select the digits I need. But I can't figure out how to convert the newly formed character string into an integer. It won't accept Integer.parseInt ..well it compiles ok, but always throws up an error when it runs.

Am I doing something blatantly obvious or is their a trick to converting either a char array or a string from a text file into an integer?

I'm just using the following lines to test if it works.

String nmbrs = contents.toString();
System.out.println(nmbrs);

// char[] textArray = new char[3];
// nmbrs.getChars(9, 12, textArray, 0);
// System.out.println(textArray);

int difx;
difx=Integer.parseInt(nmbrs);
System.out.println(difx+1);

Can anyone see what I'm doing wrong?

Again, thanks for the help guys

[Norm]

Quote:

always throws up an error when it runs.

Copy and paste the full text of the error message.
Show the output from your program. You have println()s, what do they show?
Also show some of the data file that you are reading.

[2potatocakes]

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.FileNotFoundException;
import java.io.IOException;

public class ReadTextFile
{
public static void main(String[] args)
{
File file = new File("c:\\myjava\\test.txt");
StringBuffer contents = new StringBuffer();
BufferedReader reader = null;

try
{
reader = new BufferedReader(new FileReader(file));
String text = null;

while ((text = reader.readLine()) != null)
{
contents.append(text)
.append(System.getProperty("line.separator"));
}
} catch (FileNotFoundException e)
{
e.printStackTrace();
} catch (IOException e)
{
e.printStackTrace();
} finally
{
try
{
if (reader != null)
{
reader.close();
}
} catch (IOException e)
{
e.printStackTrace();
}
}
String text = contents.toString();
System.out.println(text);

char[] textArray = new char[3];
text.getChars(9, 12, textArray, 0);
System.out.println(textArray);

int difx;
difx=Integer.parseInt(text);
System.out.println(difx+1);
}
}

And the error outputs:

The current directory is: @MyProjects
61541116546878646541321357687461351354638541351864 1 <-- this is the full number in my text file

468 <-- the getChars numbers

Exception in thread "main" java.lang.NumberFormatException: For input string: "6154111654687864654132135768746135135463854135186 41
"
at java.lang.NumberFormatException.forInputString(Num berFormatException.java:48)
at java.lang.Integer.parseInt(Integer.java:459)
at java.lang.Integer.parseInt(Integer.java:497)
at ReadTextFile.main(ReadTextFile.java:57)
Interactive Session Ended

What do you think?

[Norm]

How big an integer value do you want to get? 2G is max
How many characters are you trying to convert to an int?
It looks like too many. Look at the BigInteger class.

Comment: add comments to the println() to id what is being output. For example:
System.out.println("text=" + text + "<");
I can't easily tell what your program has printed and what you have typed in. I need to see what the program is outputing, EXACTLY.