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[Shippou]

Here is the code I keep getting errors on when I uncommment the .set() and the .add() lines

// List Test
import java.util.*;
public class ListMaking {
  public static void main(String args[])  {
   List<String> listname = new ArrayList<String>();
   //listname.add(0,"he");
   //listname.set(1,"she");
   listname.add("foo");
   listname.add("bar");
   listname.remove("xx");
   listname.remove(4);
   listname.size();
   listname.get(0);
   System.out.println(listname.get(0) + " ");
  
}}

The errors are

Exception in thread "main" java.lang.IndexOutOfBoundsException: Index: 1, Size: 1
at java.util.ArrayList.rangeCheck(Unknown Source)
at java.util.ArrayList.set(Unknown Source)
at ListMaking.main(ListMaking.java:7)

What is the issue here ?

[Angex]

You can only use the "set(...)" method to replace an existing element. It will not add a new element.

The value you specify as the index must be >= 0 and < size.

NB: Size, is the number of elements in the list, not the capacity.

You cannot do this either:

ArrayList<String> list = new ArrayList<String>( 10 );

list.set(5, "Hello");  // Will throw an exception!