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Help with ArrayList error

 
Tempora Telora
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Hey guys here is my code. It is having a problem with returning the arraylist list. Please help me figure out my problem

import java.util.ArrayList;
import java.io.*;
public class Methods
{

 
Michael Dunn
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there's nothing wrong in the return of the ArrayList
stripping all the readFile code leaves this, which returns OK



your problem must be in the file reading.
if the structure of the file is to have the first line indicate how many lines there are:
//read first line use for loop
int i = Integer.parseInt(br.readLine());

perhaps if you wrap the adding to the arraylist into a conditional
object = br.readLine();
list.add(object);

becomes
if((object = br.readLine()) != null)
{
list.add(object);
}
 
Ernest Friedman-Hill
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Actually, stripping all the file reading code leaves this (formatting cleaned up):



The problem is that "list" is declared inside the try block, so that it's only visible inside that try block; but the code tries to use it at the last line, which is outside the try, so "list" is undefined.

Just move the line that declares the ArrayList:



Now "list" is visible to all the code in the whole function.
 
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