Here is an example of how to use the FileEqualsFileFilter class from the org.apache.commons.io package in Java:

import java.io.File;
import org.apache.commons.io.filefilter.FileEqualsFileFilter;

public class FileEqualsFileFilterExample {
    public static void main(String[] args) {
        // Create a File object representing the file you want to check for equality
        File fileToCompare = new File("example.txt");

        // Create a FileEqualsFileFilter that only accepts the specific file
        FileEqualsFileFilter fileEqualsFileFilter = new FileEqualsFileFilter(fileToCompare);

        // Use the filter to check if a file in the current directory is equal to the fileToCompare
        File dir = new File(".");
        File[] files = dir.listFiles(fileEqualsFileFilter);
        if (files.length > 0) {
            System.out.println(files[0].getName() + " is equal to " + fileToCompare.getName());
        } else {
            System.out.println("No file in the current directory is equal to " + fileToCompare.getName());
        }
    }
}

In this example, we create a File object representing the file you want to check for equality and then create a FileEqualsFileFilter that only accepts the specific file.

Then we use the filter to check if a file in the current directory is equal to the fileToCompare by calling the listFiles() method on a File object representing the current directory, and passing in the fileEqualsFileFilter object as an argument.

It compares the file by the file path, not by the content of the file.

You can also use FileFilterUtils.nameFileFilter(String) to filter files by name.

import java.io.File;
import org.apache.commons.io.filefilter.FileFilterUtils;

public class FileEqualsFileFilterExample {
    public static void main(String[] args) {
        // Create a FileFilterUtils that only accepts files with a specific name
        FileFilter fileNameFilter = FileFilterUtils.nameFileFilter("example.txt");

        // Use the filter to check if a file in the current directory is equal to the fileToCompare
        File dir = new File(".");
        File[] files = dir.listFiles(fileNameFilter);
        if (files.length > 0) {
            System.out.println(files[0].getName() + " is equal to example.txt");
        } else {
            System.out.println("No file in the current directory is equal to example.txt");
        }
    }
}

In this example, the FileFilterUtils.nameFileFilter("example.txt") will return a filter that only accepts files with the name of "example.txt"