https://www.graalvm.org/ 
final class com.oracle.truffle.polyglot.HostClassLoader$FolderLoader implements com.oracle.truffle.polyglot.HostClassLoader$Loader
  minor version: 0
  major version: 59
  flags: flags: (0x0030) ACC_FINAL, ACC_SUPER
  this_class: com.oracle.truffle.polyglot.HostClassLoader$FolderLoader
  super_class: java.lang.Object
{
  private final com.oracle.truffle.api.TruffleFile root;
    descriptor: Lcom/oracle/truffle/api/TruffleFile;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  void <init>(com.oracle.truffle.api.TruffleFile);
    descriptor: (Lcom/oracle/truffle/api/TruffleFile;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.oracle.truffle.polyglot.HostClassLoader$FolderLoader this
        start local 1 // com.oracle.truffle.api.TruffleFile root
         0: .line 292
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 293
            aload 0 /* this */
            aload 1 /* root */
            putfield com.oracle.truffle.polyglot.HostClassLoader$FolderLoader.root:Lcom/oracle/truffle/api/TruffleFile;
         2: .line 294
            return
        end local 1 // com.oracle.truffle.api.TruffleFile root
        end local 0 // com.oracle.truffle.polyglot.HostClassLoader$FolderLoader this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    3     0  this  Lcom/oracle/truffle/polyglot/HostClassLoader$FolderLoader;
            0    3     1  root  Lcom/oracle/truffle/api/TruffleFile;
    MethodParameters:
      Name  Flags
      root  

  public com.oracle.truffle.polyglot.HostClassLoader$Resource findResource(java.lang.String);
    descriptor: (Ljava/lang/String;)Lcom/oracle/truffle/polyglot/HostClassLoader$Resource;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=4, locals=3, args_size=2
        start local 0 // com.oracle.truffle.polyglot.HostClassLoader$FolderLoader this
        start local 1 // java.lang.String name
         0: .line 298
            aload 0 /* this */
            getfield com.oracle.truffle.polyglot.HostClassLoader$FolderLoader.root:Lcom/oracle/truffle/api/TruffleFile;
            aload 1 /* name */
            invokevirtual com.oracle.truffle.api.TruffleFile.resolve:(Ljava/lang/String;)Lcom/oracle/truffle/api/TruffleFile;
            astore 2 /* file */
        start local 2 // com.oracle.truffle.api.TruffleFile file
         1: .line 299
            aload 2 /* file */
            iconst_0
            anewarray java.nio.file.LinkOption
            invokevirtual com.oracle.truffle.api.TruffleFile.isRegularFile:([Ljava/nio/file/LinkOption;)Z
            ifne 3
         2: .line 300
            aconst_null
            areturn
         3: .line 302
      StackMap locals: com.oracle.truffle.api.TruffleFile
      StackMap stack:
            new com.oracle.truffle.polyglot.HostClassLoader$FolderLoader$1
            dup
            aload 0 /* this */
            aload 2 /* file */
            invokespecial com.oracle.truffle.polyglot.HostClassLoader$FolderLoader$1.<init>:(Lcom/oracle/truffle/polyglot/HostClassLoader$FolderLoader;Lcom/oracle/truffle/api/TruffleFile;)V
            areturn
        end local 2 // com.oracle.truffle.api.TruffleFile file
        end local 1 // java.lang.String name
        end local 0 // com.oracle.truffle.polyglot.HostClassLoader$FolderLoader this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    4     0  this  Lcom/oracle/truffle/polyglot/HostClassLoader$FolderLoader;
            0    4     1  name  Ljava/lang/String;
            1    4     2  file  Lcom/oracle/truffle/api/TruffleFile;
    MethodParameters:
      Name  Flags
      name  

  public void close();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=0, locals=1, args_size=1
        start local 0 // com.oracle.truffle.polyglot.HostClassLoader$FolderLoader this
         0: .line 332
            return
        end local 0 // com.oracle.truffle.polyglot.HostClassLoader$FolderLoader this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/polyglot/HostClassLoader$FolderLoader;
    Exceptions:
      throws java.io.IOException
}
SourceFile: "HostClassLoader.java"
NestHost: com.oracle.truffle.polyglot.HostClassLoader
InnerClasses:
  private final FolderLoader = com.oracle.truffle.polyglot.HostClassLoader$FolderLoader of com.oracle.truffle.polyglot.HostClassLoader
  com.oracle.truffle.polyglot.HostClassLoader$FolderLoader$1
  private abstract Loader = com.oracle.truffle.polyglot.HostClassLoader$Loader of com.oracle.truffle.polyglot.HostClassLoader
  private abstract Resource = com.oracle.truffle.polyglot.HostClassLoader$Resource of com.oracle.truffle.polyglot.HostClassLoader