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java.lang.ArrayIndexOutOfBoundsException

keepworking
keepworking asked
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Last Modified: 2012-08-14
The index of an Arraylist can be infinite?
the follow code works for a small set files, but it got "java.lang.ArrayIndexOutOfBoundsException" when it works on a set of hug size files,

I cleared the arraylist everytime, why I got this kind of error? how to fix it?
 thanks


//to get the unique entries in a txt file, so from original.txt file
1  apple
2  orange
3  apple
4  orange
I will get unique.txt with:
apple
orange


 public static void get_unique(File file, String dir) throws IOException{
       
        BufferedReader in = new BufferedReader(new FileReader(file.getAbsolutePath()));
        String str ;
        String[] entry = null;

        ArrayList unique_list = new ArrayList();
       
        while ((str =in.readLine())!= null && !str.equals(""))
        {
            entry = str.split("\t");
            String text = entry[1];
           
            if (unique_list!=null){
               
                if (unique_list.size()==0)
                {unique_list.add(text);}
               
                else{
                    for (int i =0; i<unique_list.size(); i++){
                        if (!unique_list.contains(text))
                        {
                            unique_list.add(text);
                        }
                    }
                       
                }//end of for
            }//end of if    
        }//end of while
        in.close();
        unique_list.clear();    
    }
   
   
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Commented:
yes, both of you are right,

the problem is

String text = entry[1];
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here is the fixed code

String str;
        String[] entry = null;

        ArrayList unique_list = new ArrayList();

        while ((str = in.readLine()) != null && !str.equals(""))
        {
            entry = str.split("\t");
            if(entry.length>1)
            {
                String text = entry[1];

                if (!unique_list.contains(text))
                {
                    unique_list.add(text);
                }
            }
        } //end of while
        in.close();
        for (int i = 0; i < unique_list.size(); i++)
        {
            System.out.println(unique_list.get(i));
        }
        unique_list.clear();

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