ArrayOutOf Bound Exception

[shalini gnana]

I tried to convert arraylist(object) into string and then into date..I'm getting the following exception..How to avoid this and make my program run...

   java.lang.IndexOutOfBoundsException: Index: 21, Size: 21
        at java.util.ArrayList.RangeCheck(ArrayList.java:546)
        at java.util.ArrayList.get(ArrayList.java:321)
        at saxExamples.DataReader.list(DataReader.java:94)
        at saxExamples.DataReader.main(DataReader.java:110)
 

  
package saxExamples;
 
import java.io.FileNotFoundException;
import java.io.IOException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import org.xml.sax.SAXException;
 
public class DataReader 
{
    protected ArrayList<DataObject> res_mseg;
    protected ArrayList<DrawingData> rev_list;
    protected ArrayList<FromDateData> frm_list;
    protected ArrayList<WrkorderData> wrk ;
       
    public DataReader(){
        res_mseg = new ArrayList<DataObject>();
        rev_list = new ArrayList<DrawingData>();
               
    }
    
    public void getData()throws Exception
    {
    
        XMLReading xmlreadingObj = new XMLReading();
        xmlreadingObj.fileParsing("C:/Documents and Settings/Gantt.xml");
        xmlreadingObj.print();
        xmlreadingObj.printDrawingData();
        xmlreadingObj.printFromdate();
        xmlreadingObj.printToDate();
        xmlreadingObj.printToTime();
        xmlreadingObj.printFrmtime();
        
        
    }
    public void list() throws SAXException, FileNotFoundException, IOException, ParseException
    {
      
        XMLReading xmlreadingObj = new XMLReading();
        xmlreadingObj.fileParsing("C:/Documents and Settings/Gantt.xml");
        
        res_mseg = xmlreadingObj.res_list;
        Object [] array = res_mseg.toArray();
        
        rev_list = xmlreadingObj.rev__wrkOrder_list;
        Object [] array1 = rev_list.toArray();
        
        wrk = new ArrayList<WrkorderData>();
        wrk = xmlreadingObj.wrkorder_list;
        
        frm_list = xmlreadingObj.rev_frmdate_list;
                                      
        String str1 = new String();
        String str2 = new String();
        ArrayList<String> list = new ArrayList();
        ArrayList list1 = new ArrayList();
        ArrayList<Date> l = new ArrayList<Date>();
       
        for(int len = 0; len < array.length; len++)
        {
           str1 = array[len].toString();
           for(int len1 = 0; len1 < array1.length; len1++)
           {
               str2 = array1[len1].toString();
               if(str1.compareToIgnoreCase(str2) == 0 )
               {     
                   list.add(frm_list.get(len1).toString());
                   list1.add(wrk.get(len1));
               }
            
            }
           
           for(int wrk_len= 0;wrk_len<wrk.size();wrk_len++)
                   {
                        String str = list.get(wrk_len).toString();
                        SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");
                        Date date = df.parse(str);
                       
                        l.add(date);
                                                
                   }
            System.out.println(l.get(0).getTime()-l.get(1).getTime());
            list.clear();
          }
    }
       
public static void main(String args[])
    {
        DataReader Obj = new DataReader();
       
        try 
        {
           Obj.list();
            //Obj.getData(); 
        }
        catch (Exception ex) 
        {
            ex.printStackTrace();
        }
    } 
 
    
   
}  

[Deepak Chopra]

Hi,
The problem is difficult to track..because of Variable names and we don't know what is the output when you parsed the XML File, still I can tell you how to track your problem, as per my understanding problem lies in the following part of code :

  
for(int len = 0; len < array.length; len++)
            {
               str1 = array[len].toString();
               for(int len1 = 0; len1 < array1.length; len1++)
               {
                   str2 = array1[len1].toString();
                   if(str1.compareToIgnoreCase(str2) == 0 )
                   {     
                       list.add(frm_list.get(len1).toString());
                       list1.add(wrk.get(len1));
                   }
                
                }
    /*******************************************************************/
   /* WE DONT KNOW THE SIZE OF list AND list1 HERE,AS THEY ARE BUILDING  DYNAMICALLY, SO BEFORE USING THEM TO RETRIEVE THE VALUE OF OBJECT, YOU NEED TO MAKE A CHECK*/
    /*******************************************************************/            
               for(int wrk_len= 0;wrk_len<wrk.size();wrk_len++)
                       {
                            
String str = list.get(wrk_len).toString();
                            SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");
                            Date date = df.parse(str);
                           
                            l.add(date);
                                                    
                       }
                System.out.println(l.get(0).getTime()-l.get(1).getTime());
                list.clear();
              }
        }
  

You can try the following modification:

for(int len = 0; len < array.length; len++)
            {
               str1 = array[len].toString();
               for(int len1 = 0; len1 < array1.length; len1++)
               {
                   str2 = array1[len1].toString();
                   if(str1.compareToIgnoreCase(str2) == 0 )
                   {     
                       list.add(frm_list.get(len1).toString());
                       list1.add(wrk.get(len1));
                   }
                
                }
               
               for(int wrk_len= 0;wrk_len<wrk.size();wrk_len++)
                       {
                            if(list.size( ) < wrk_len )// adding the if code..to check the size before retrieving any value..!! to avoid Exception
   {
String str = list.get(wrk_len).toString();
                            SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");
                            Date date = df.parse(str);
                           
                            l.add(date);
   }
   else  // in case size is less..than simply come out of the loop...!!
   {
   // System.out.println( " Print any necessary message here");
     break;   
   }
                                                    
                       }
if(l.size( ) >= 2)
{
                System.out.println(l.get(0).getTime()-l.get(1).getTime());
}
                list.clear();
              }
        }

This is as per my understanding of the code.

[Deepak Chopra]

Oops !! I made the wrong if condition..!! I am sorry..!!
Please modify it :

if( wrk_len < list.size( ) )