import java.io.IOException; import javax.servlet.Filter; import javax.servlet.FilterChain; import javax.servlet.FilterConfig; import javax.servlet.ServletException; import javax.servlet.ServletRequest; import javax.servlet.ServletResponse; public class BasicFilter implements Filter { private FilterConfig filterConfig; public void init(FilterConfig filterConfig) throws ServletException { System.out.println("Filter initialized"); this.filterConfig = filterConfig; } public void destroy() { System.out.println("Filter destroyed"); this.filterConfig = null; } public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException { System.out.println("doFilter"); chain.doFilter(request, response); } }