Filter Files in Java

Introduction
The Filter File Java example code provides the following functionalities:
- Filtering the files depending on the file extension provided by the user
- User provides the file extension and then program lists all the matching
files found
Program accepts directory name and file extension from user and displays the
files present in the directory.
Program begins with import statement java.io.*;
package, which is required for any input/output operations.
Classes Defined in the program:
OnlyExt
The constructor of the class takes file extension as parameter and then
prefix it with "*." and assign into the global variable ext.
The OnlyExt class implements FilenameFilter interface, so we have to implement
the abstract method accept( ) defined in the
FilenameFilter interface. The accept( )
method tests if a specified file should be included in a file list.
FilterFiles:
The FilterFiles contains the public static void main(String args[]),
which is the entry point of our program. The program first accepts
directory name and file extension from the user and creates the object of
OnlyExt class passing file extension as constructor parameter.
Here is the code of the program :
import java.io.*;
class OnlyExt implements FilenameFilter{
String ext;
public OnlyExt(String ext){
this.ext="." + ext;
}
public boolean accept(File dir,String name){
return name.endsWith(ext);
}
}
public class FilterFiles{
public static void main(String args[]) throws IOException{
BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
System.out.println("Please enter the directory name : ");
String dir = in.readLine();
System.out.println("Please enter file type : ");
String extn = in.readLine();
File f = new File(dir);
FilenameFilter ff = new OnlyExt(extn);
String s[] = f.list(ff);
for (int i = 0; i < s.length; i++){
System.out.println(s[i]);
}
}
}
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Current Comments
3 comments so far (post your own) View All Comments Latest 10 Comments:in that program u impement FileNameFilter.but u could not used this interface methods.so why u implement that interface
Posted by srinivas on Monday, 05.21.07 @ 18:54pm | #16924
where the class FilenameFilter is present
Posted by subh on Friday, 05.4.07 @ 12:00pm | #15255
Yes,it worked succesfully,thanks!!
Posted by TIJI on Friday, 12.29.06 @ 11:37am | #2196