File Extension Validation Example Code

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class ImageValidator{

    private Pattern pattern;
    private Matcher matcher;

    private static final String File_PATTERN =
            "([^\\s]+(\\.(?i)(jpg|png|doc|docx|pdf))$)";

    public ImageValidator(){
        pattern = Pattern.compile(IMAGE_PATTERN);
    }

    /**     * Validate image with regular expression     * @param filename image for validation     * @return true valid image, false invalid image     */    public boolean validate(final String filename){

        matcher = pattern.matcher(filename);
        return matcher.matches();

    }
}



Call Function :


boolean ImageValidator = new ImageValidator().validate(filePath.toLowerCase()) ? true : false;