Get object for index

int indexOf(Object o)
Returns the index of the first occurrence, or -1 if this list does not contain the element.
int lastIndexOf(Object o)
Returns the index of the last occurrence, or -1 if this list does not contain the element.

  import java.util.ArrayList;

public class Main {
  public static void main(String args[]) {
    ArrayList<String> al = new ArrayList<String>();

    al.add("C");
    al.add("java2s.com");
    al.add("D");
    al.add("F");
    al.add(1, "java2s.com");

    System.out.println(al);
    System.out.println(al.indexOf("java2s.com"));
    System.out.println(al.lastIndexOf("java2s.com"));

  }

}

The output: 


[C, java2s.com, java2s.com, D, F]
1
2
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ArrayList:
  1. ArrayList Class
  2. Create ArrayList object
  3. Add to ArrayList
  4. Clear an ArrayList
  5. Shallow copy of current ArrayList
  6. If contain a certain object
  7. Increases the capacity of an ArrayList
  8. Get/Replace element by index
  9. Get object for index
  10. Remove from ArrayList
  11. Get the size and trim to size
  12. If ArrayList is empty
  13. Convert ArrayList to array