Listing Directory using Regular expression

This Example describe the way how to list the directory by using Regularexpression.

Listing Directory using Regular expression

Listing Directory using Regular expression

     

This Example describe the way how to list the directory by using Regularexpression.The steps involved in replacing a String are described below:

File directorypath = new File("/home/girish/Desktop/Linux"):-it is the path where my directory is stored.Before running this example create your own directory and give the path of the directory.

String[] list:-Creates an array named list.

list = directorypath.list():-This method returns array of string including the files and directories in the directory followed by this abstract pathname.

list = directorypath.list(new DirFilter(args[0])):-This method returns array of string including the files and directories in the directory followed by this abstract pathname that suits the specified filter.

public boolean accept(File directorypath, String name):-This method is for testing if a specified file should be included in a file list.

pattern = Pattern.compile(regex):-This method compiles the regular expression into a pattern.

 
Listdirectory.java
import java.io.File;
import java.io.FilenameFilter;
import java.util.regex.Pattern;

public class Listdirectory {
  public static void main(String[] args) {
  File directorypath = new File("/home/girish/Desktop/Linux");
  String[] list;
  if (args.length == 0)
  list = directorypath.list();
   else
  list = directorypath.list(new DirFilter(args[0]));
 for (int i = 0; i < list.length; i++)
  System.out.println(list[i]);
  }
}
 class DirFilter implements FilenameFilter {
  private Pattern pattern;

  public DirFilter(String regex) {
  pattern = Pattern.compile(regex);
  }
  public boolean accept(File directorypath, String name) {
 return pattern.matcher(new File(name).getName()).matches();
  }
}

Output of the program:-

linux.doc
new file~
song
new file
Xmlroseindia.odt

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Tutorials

  1. Matching Pattern using Regularexpression
  2. Interchanging String using RegularExpression
  3. Split Demo using RegularExpression
  4. Replacing String using Regularexpression
  5. Print Matchingwords using Regular expression
  6. Listing Directory using Regular expression
  7. Calculating Repetingwords using Regular expression
  8. Retrieving String by using Regular Expression
  9. Retrieving String after given Regular expression
  10. Retrieve the String using expression
  11. Matching Address using regular expressions
  12. Finding a given word using regular expression
  13. Replacing the first subsequence of the input
  14. Pointing last index of the Matcher
  15. Pointing and indicating matcher using regular expression
  16. Finding word using regular expression
  17. Appending and replacing string using regular expression
  18. Split string after each character using regular expression
  19. Reset the matcher using regular expression
  20. Replacing all the text of String using expression
  21. Pattern resetting using regular expression
  22. Match string using regular expression without Case sensitivity
  23. Matching Zip code using regular expression
  24. Finding start and end index of string using Regular expression
  25. Regular Expressions