How to delete files with certain extension only ?

How to delete files with certain extension only ?

// Implementing FilenameFilter

public class GenericExtFilter implements FilenameFilter {

  private String ext;

  public GenericExtFilter(String ext) {

    this.ext = ext;

  }

  public boolean accept(File dir, String name) {

    return (name.endsWith(ext));

  }

}

// Using filename filter subclass

GenericExtFilter filter = new GenericExtFilter(".txt");

private static final String FILE_DIR = "c:\\folder";

File dir = new File(FILE_DIR);

String[] list = dir.list(filter);

File fileDelete;

for (String file : list){

  String temp = new StringBuffer(FILE_DIR).append(File.separator)

                        .append(file).toString();

  fileDelete = new File(temp);

  boolean isdeleted = fileDelete.delete();

  System.out.println("file : " + temp + " is deleted : " + isdeleted);

}