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POlist.add not working with ArrayList
 

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    <p>I am trying to add integers from a file into an ArrayList and list.add doesn't want to work. I've only tried about a thousand different ways to write this code. The <code>list.add(s.next());</code> line gives an error in Eclipse, </p> <blockquote> <p><code>The method add(Integer) in the type List&lt;Integer&gt; is not applicable for the arguments (String).</code> </p> </blockquote> <p>Sounds like I am somehow trying to do something with an integer that can only be done with a string, but I need them to remain integers and if I hadn't been searching, studying and cramming my head with Java for the last 5 days straight I could probably understand what it means.</p> <p>I can get it to work with a regular array just fine, but my ArrayList collection is a real pain and I'm not sure what I'm doing wrong. Any help would be much appreciated. </p> <p>Thanks in advance.</p> <hr> <pre><code>import java.io.BufferedReader; import java.io.File; import java.io.FileNotFoundException; import java.io.FileReader; import java.io.IOException; import java.util.ArrayList; import java.util.Collections; import java.util.List; import java.util.Scanner; public class MyCollection { @SuppressWarnings({ "rawtypes", "unchecked" }) public static void main(String[] args) { List&lt;Integer&gt; list = new ArrayList(); //---- ArrayList 'list' Scanner s = new Scanner(new File("C:/Users/emissary/Desktop/workspace/stuff/src/numbers.txt")); while (s.hasNext()) { list.add(s.next()); } s.close(); Collections.sort(list); for (Integer integer : list){ System.out.printf("%s, ", integer); } } } </code></pre>
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    1. CO`Scanner#next()` returns a String, you want `Scanner#nextInt()`. This will also require some more specific file handling (`hasNextInt()`) and skipping new lines depending on your format of your txt file.
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      1. USSotirios Delimanolis
 

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