ArrayList indexOf

[tk harvey]

My goal is to write a report generator that keeps a running total of alarm messages in a .csv file. I have condensed my original code down to this snippet that is used to see if an alarm message (read from an input file as �LineIn�) is already in my list, and if so, use its indexOf value for updating the running-count (also contained on the same comma-delimted line as the message) later on.

I�m at a loss to understand why the indexOf doesn�t work as I expect and my frustration has grown to the point where I�m ready to ditch this and write it in PERL/ksh.

The AHC.get returns exactly what I expect, the 4th line of my .csv file (and it indeed contains the string "CarbonAlarm"), but the AHC.indexOf always returns -1. Based on what I have read here in the Saloon, it probably has something to do with the �String LineIn�. I would be forever in debt to someone who would please explain to me what is going on.
EEEEKS!! where did my formatting go after cut&paste???
I hope ya'll can read this...

import java.io.* ;
import java.util.* ;
 
public class pe
{
   public static void main(String[] args)
   {
     ReadFileToList ReadFile = new ReadFileToList() ;
     ArrayList AHC = new ArrayList() ;
     int CurrentAlarmLinesRead = 0 ;
     CurrentAlarmLinesRead = ReadFile.ReadFileToList("AlarmHistory.csv", AHC) ;
     String LineIn = "CarbonAlarm" ;
     System.out.println("ahcStuff=="+AHC.get(3)+"=="+AHC.indexOf(LineIn)+"\n") ;
   }
}

now, i guess i'd better go find the FAQ about formatting...
[ November 15, 2007: Message edited by: tk harvey ]

[Adam Schaible]

First thing is I would also refer to the list by it's interface, List - so
List ACH = new ArrayList();

You mention that the fourth line of the csv contains the string "CarbonAlarm" - but if you read the javadoc for the indexOf method you will see:

indexOf
public int indexOf(Object elem)Searches for the first occurence of the given argument, testing for equality using the equals method. 
 
Specified by:
indexOf in interface List
Overrides:
indexOf in class AbstractList
Parameters:
elem - an object. 
Returns:
the index of the first occurrence of the argument in this list; returns -1 if the object is not found.
See Also:
Object.equals(Object)

So unless the fourth line of your CSV .equals("CarbonAlarm"), the indexOf method will not return the that index.
[ November 15, 2007: Message edited by: Adam Schaible ]

[tk harvey]

Oh okay, it's the old "Returns:the index of the first occurrence of the *entire 10-field* argument in this list;" usage. My face is red... THanks! for your help!