https://openjdk.java.net/ 
public interface java.io.FilenameFilter
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: java.io.FilenameFilter
  super_class: java.lang.Object
{
  public abstract boolean accept(java.io.File, java.lang.String);
    descriptor: (Ljava/io/File;Ljava/lang/String;)Z
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    MethodParameters:
      Name  Flags
      dir   
      name  
}
SourceFile: "FilenameFilter.java"
    RuntimeVisibleAnnotations: 
      java.lang.FunctionalInterface()