Question

This is my first post here so kindly pardon any mistakes that I have. I’m still learning to find my way around Stack Exchange.

I am trying to write a Java program that tries to scan a Directory full of either .txt,.rtf or.doc files(and none other). The aim is to search all the files in the directory, and find out if a particular string exists in the file. If it does, it returns the string and the filename that it found the string in.

The aim of this program is, it is a project for school wherein the program scans the personal folders of call center employees to check if they have stored any CC/DC nos and if yes, report the folder name – to reduce CC fraud.

The search function was fairly straight forward and works when I individually specify the filename. However, the searching the directory and passing the files to the search function has me stumped.

I’ve posted my code so far, if you guys could look thru it and give me some feedback/suggestions, I’d really appreciate it. Thanks in advance

import java.io.*;
import java.util.*;

public class parse2{

void traverse(String directory) throws FileNotFoundException   
    {  
        File dir = new File(directory);  
            if (dir.isDirectory())  
        {  
                   String[] children = dir.list();  
                   for (int i=0; i<children.length; i++)   
                {  
            //System.out.println("\n" + children[i]);
                    reader(children[i]);  
                }  
            }  

     }


void reader(String loc) throws FileNotFoundException
{   //System.out.println("\nC:/Documents and Settings/h4d35/Desktop/javatest/chk/"+loc);
    String s = ("C:/Documents and Settings/h4d35/Desktop/javatest/chk/"+loc);
    //System.out.println("\n"+s);
            FileReader fr = new FileReader(loc);
    BufferedReader br = new BufferedReader(fr);
    Scanner sc = new Scanner(br);
    char[] chkArray;
    int chk=1;
    char ch;
    while(sc.hasNext())
    {
        String chkStr = sc.next();
        chkArray = chkStr.toCharArray();
        if ((chkArray[0]=='4')&&(chkStr.length()>13))
        {   for(int i=0;i<chkArray.length;i++)
            {   ch=chkArray[i];
                if((ch=='0')||(ch=='1')||(ch=='2')||(ch=='3')||(ch=='4')||(ch=='5')||(ch=='6')||(ch=='7')||(ch=='8')||(ch=='9'))
                {   chk=0;
                    continue;
                }
                else 
                {   chk=1;
                    break;
                }
            }
            if(chk==0)
                System.out.println("\n"+ chkStr);
        }
        else
        if((chkArray[0]=='5')&&(chkStr.length()>13))
        {   for(int i=0;i<chkArray.length;i++)
            {   ch=chkArray[i];
                if((ch=='0')||(ch=='1')||(ch=='2')||(ch=='3')||(ch=='4')||(ch=='5')||(ch=='6')||(ch=='7')||(ch=='8')||(ch=='9'))
                {   chk=0;
                    continue;
                }
                else 
                {   chk=1;
                    break;
                }
            }
            if(chk==0)
            System.out.println("\n"+ chkStr);
        }
        else
        if((chkArray[0]=='6')&&(chkStr.length()>13))
        {   for(int i=0;i<chkArray.length;i++)
            {   ch=chkArray[i];
                if((ch=='0')||(ch=='1')||(ch=='2')||(ch=='3')||(ch=='4')||(ch=='5')||(ch=='6')||(ch=='7')||(ch=='8')||(ch=='9'))
                {   chk=0;
                    continue;
                }
                else 
                {   chk=1;
                    break;
                }
            }
            if(chk==0)
            System.out.println("\n"+ chkStr);
        }
    }
}

public static void main(String args[]) throws FileNotFoundException
{   
    parse2 P = new parse2();
    P.traverse("C:/Documents and Settings/h4d35/Desktop/javatest/chk");
}

}

**

• EDIT : The variable “loc” only gives the file name – so I added the rest of the path to it under the String variable “s”. There’s no output. When I uncomment Line 3 of reader() function, it shows the absolute path of all the files. I tried the reader() function on its own by explicitly specifying the absolute path and it worked. Code below:

  import java.io.*;

  import java.util.*;

public class parse1{

void read() throws FileNotFoundException
{   FileReader fr = new FileReader("C:/Documents and Settings/h4d35/Desktop/javatest/chk/Call back customer.txt");
    BufferedReader br = new BufferedReader(fr);
    Scanner sc = new Scanner(br);
    char[] chkArray;
    int chk=1;
    char ch;
    while(sc.hasNext())
    {
        String chkStr = sc.next();
        chkArray = chkStr.toCharArray();
        if ((chkArray[0]=='4')&&(chkStr.length()>13))
        {   for(int i=0;i<chkArray.length;i++)
            {   ch=chkArray[i];
                if((ch=='0')||(ch=='1')||(ch=='2')||(ch=='3')||(ch=='4')||(ch=='5')||(ch=='6')||(ch=='7')||(ch=='8')||(ch=='9'))
                {   chk=0;
                    continue;
                }
                else 
                {   chk=1;
                    break;
                }
            }
            if(chk==0)
                System.out.println("\n"+ chkStr);
        }
        else
        if((chkArray[0]=='5')&&(chkStr.length()>13))
        {   for(int i=0;i<chkArray.length;i++)
            {   ch=chkArray[i];
                if((ch=='0')||(ch=='1')||(ch=='2')||(ch=='3')||(ch=='4')||(ch=='5')||(ch=='6')||(ch=='7')||(ch=='8')||(ch=='9'))
                {   chk=0;
                    continue;
                }
                else 
                {   chk=1;
                    break;
                }
            }
            if(chk==0)
            System.out.println("\n"+ chkStr);
        }
        else
        if((chkArray[0]=='6')&&(chkStr.length()>13))
        {   for(int i=0;i<chkArray.length;i++)
            {   ch=chkArray[i];
                if((ch=='0')||(ch=='1')||(ch=='2')||(ch=='3')||(ch=='4')||(ch=='5')||(ch=='6')||(ch=='7')||(ch=='8')||(ch=='9'))
                {   chk=0;
                    continue;
                }
                else 
                {   chk=1;
                    break;
                }
            }
            if(chk==0)
            System.out.println("\n"+ chkStr);
        }
    }
}

public static void main(String args[]) throws FileNotFoundException
{   
    parse1 P = new parse1();
    P.read();
}

}

**

Answer 1

The biggest problem I see is that you should instead be recursively calling traverse() on directories, and should only call reader() on files. You should also try stepping through the problematic lines of code in a debugger. It’s really easy to set breakpoints and step through your code in Eclipse or probably any other IDE.

You can easily filter by filename extension using the built-in API. Check out FilenameFilter and File.list(FilenameFilter) or (preferably) File.listFiles(FilenameFilter). Whenever possible, you should try to avoid storing file and directory paths as Strings–instead, use File objects.

Your reader method could be simplified by using String.matches(...) or String.regionMatches(...). Both of these methods (and similar ones) are regular expression comparisons–take a look at the Pattern class, in particular. Since you’re repeating the same comparisons a lot, you may want to create one or more Patterns to reuse over and over, but that’s just a performance optimization.