Read file from directory, update contents of the each file

[svpriyan]

hai,
I could not understand how to debug the error i have now.
target
1- read the files from directory // i able ot do this part
2- for each file
for each file read the content & compare with the existing List & update the list // i able to do this part

when i try to combine both parts , i got some following error

run:
E:\java\check\100130.ixf
Error: children[i] (The system cannot find the file specified)
BUILD SUCCESSFUL (total time: 2 seconds)

i can see from the code that children[i] only gives the error when i use that in the second part of the code.

can any one help me on this??
Thanks
Priyan


the original code

 

import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStreamReader;
import java.io.RandomAccessFile;
import java.util.ArrayList;


public class CompareList
	{

	public static void main(String[] args){

         ArrayList a1 = new ArrayList();
         ArrayList a2 = new ArrayList();
         a1.add("1");
         a1.add("2");
         a1.add("3");
         a1.add("4");
         a1.add("5");
         a1.add("6");
         a1.add("7");
         a1.add("8");
         a1.add("9");
         a1.add("10");
         a1.add("11");
         a1.add("12");
         a1.add("13");
         a1.add("14");
         a1.add("15");
         a1.add("16");
         a1.add("17");
         a1.add("18");
         a1.add("19");
         a1.add("20");
         a1.add("21");
         a1.add("22");
         a1.add("23");
         a1.add("24");
         a1.add("25");
         a1.add("26");
         a1.add("27");
         a1.add("28");
         a1.add("29");
         a1.add("30");
         a1.add("31");
         a1.add("32");
         a1.add("33");
         a1.add("34");
         a1.add("35");
         a1.add("36");
         a1.add("37");
         a1.add("38");
         a1.add("39");
         a1.add("40");
         a1.add("41");
         a1.add("42");
         a1.add("43");
         a1.add("44");
         a1.add("45");
         a1.add("46");
         a1.add("47");
         a1.add("48");
         a1.add("49");
         a1.add("50");
         a1.add("51");
         a1.add("52");

          try{
              
                File dir = new File("E:\\java\\check");

                File[] children = dir.listFiles();
                if (children == null) {
                      System.out.println("does not exist or is not a directory");
                 }

    else {
           for (int i = 0; i < children.length; i++) {
                   System.out.println( children[i]);
                    FileInputStream fstream = new FileInputStream("children[i]");
                    DataInputStream in = new DataInputStream(fstream);
                      BufferedReader br = new BufferedReader(new InputStreamReader(in));
                    String strLine;
                    while ((strLine = br.readLine()) != null) 	{
                   String line =strLine.substring(0,2);
                    // Print the content on the console
                     //System.out.println(line);
                     a2.add(line);
                  } // end of add list2

           if (a1.size() > a2.size())
         {
             int k = 0;
             for (int l = 0; l < a2.size(); l++)
             {
                 if (!((String)a1.get(l)).equals((String)a2.get(l)))
                 {
                     //System.out.println((String)a2.get(i));
                      // System.out.println("dd");
                 }
                 k = l;
             }
             k++;
             for (int l = k; l < a1.size(); l++)
             {
                 System.out.println((String)a1.get(l));
                String str = "children[l]";
 
                File file = new File(str);
                 RandomAccessFile rand = new RandomAccessFile(file,"rw");

                  rand.seek(file.length());  //Seek to end of file
                  rand.writeBytes((String)a1.get(i));  //Write end of file
                  rand.writeBytes("., 0.");
                  rand.writeBytes("\n");


             }
         }// end of comparing and updating the list2

		in.close();
		}
    }
     }
              catch (Exception e){//Catch exception if any
                System.err.println("Error: " + e.getMessage());
		}
	}
}

[RamyaSivakanth]

Hi,
Seeing your code I can say u are very new to Java.

One small suggestion.
Why are u adding 1,2,3...like this ...U can put a loop know?


Don't put quotes around this childern[i].
FileInputStream fstream = new FileInputStream(children[i]);

In your code ,lot of comments are there.But as a beginner I don't want to.Go thru some good Java material before starting something.

-Regards
Ramya

[Eranga]

Don't put quotes around this childern[i].
FileInputStream fstream = new FileInputStream(children[i]);

Java doc explain about this more clearly, what are the correct arguments you have to pass.