https://www.graalvm.org/ 
final class com.oracle.truffle.api.TruffleFile$FileSystemContext
  minor version: 0
  major version: 59
  flags: flags: (0x0030) ACC_FINAL, ACC_SUPER
  this_class: com.oracle.truffle.api.TruffleFile$FileSystemContext
  super_class: java.lang.Object
{
  final java.lang.Object engineObject;
    descriptor: Ljava/lang/Object;
    flags: (0x0010) ACC_FINAL

  private volatile java.util.Map<java.lang.String, java.util.Collection<? extends com.oracle.truffle.api.TruffleFile$FileTypeDetector>> fileTypeDetectors;
    descriptor: Ljava/util/Map;
    flags: (0x0042) ACC_PRIVATE, ACC_VOLATILE
    Signature: Ljava/util/Map<Ljava/lang/String;Ljava/util/Collection<+Lcom/oracle/truffle/api/TruffleFile$FileTypeDetector;>;>;

  final org.graalvm.polyglot.io.FileSystem fileSystem;
    descriptor: Lorg/graalvm/polyglot/io/FileSystem;
    flags: (0x0010) ACC_FINAL

  static final boolean $assertionsDisabled;
    descriptor: Z
    flags: (0x1018) ACC_STATIC, ACC_FINAL, ACC_SYNTHETIC

  static void <clinit>();
    descriptor: ()V
    flags: (0x0008) ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: .line 2047
            ldc Lcom/oracle/truffle/api/TruffleFile;
            invokevirtual java.lang.Class.desiredAssertionStatus:()Z
            ifne 1
            iconst_1
            goto 2
      StackMap locals:
      StackMap stack:
         1: iconst_0
      StackMap locals:
      StackMap stack: int
         2: putstatic com.oracle.truffle.api.TruffleFile$FileSystemContext.$assertionsDisabled:Z
            return
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  void <init>(java.lang.Object, org.graalvm.polyglot.io.FileSystem);
    descriptor: (Ljava/lang/Object;Lorg/graalvm/polyglot/io/FileSystem;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=3, args_size=3
        start local 0 // com.oracle.truffle.api.TruffleFile$FileSystemContext this
        start local 1 // java.lang.Object engineFileSystemContext
        start local 2 // org.graalvm.polyglot.io.FileSystem fileSystem
         0: .line 2055
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 2056
            aload 1 /* engineFileSystemContext */
            invokestatic java.util.Objects.requireNonNull:(Ljava/lang/Object;)Ljava/lang/Object;
            pop
         2: .line 2057
            aload 2 /* fileSystem */
            invokestatic java.util.Objects.requireNonNull:(Ljava/lang/Object;)Ljava/lang/Object;
            pop
         3: .line 2058
            aload 0 /* this */
            aload 1 /* engineFileSystemContext */
            putfield com.oracle.truffle.api.TruffleFile$FileSystemContext.engineObject:Ljava/lang/Object;
         4: .line 2059
            aload 0 /* this */
            aload 2 /* fileSystem */
            putfield com.oracle.truffle.api.TruffleFile$FileSystemContext.fileSystem:Lorg/graalvm/polyglot/io/FileSystem;
         5: .line 2060
            return
        end local 2 // org.graalvm.polyglot.io.FileSystem fileSystem
        end local 1 // java.lang.Object engineFileSystemContext
        end local 0 // com.oracle.truffle.api.TruffleFile$FileSystemContext this
      LocalVariableTable:
        Start  End  Slot                     Name  Signature
            0    6     0                     this  Lcom/oracle/truffle/api/TruffleFile$FileSystemContext;
            0    6     1  engineFileSystemContext  Ljava/lang/Object;
            0    6     2               fileSystem  Lorg/graalvm/polyglot/io/FileSystem;
    MethodParameters:
                         Name  Flags
      engineFileSystemContext  
      fileSystem               

  java.lang.Iterable<? extends com.oracle.truffle.api.TruffleFile$FileTypeDetector> getFileTypeDetectors(java.util.Set<java.lang.String>);
    descriptor: (Ljava/util/Set;)Ljava/lang/Iterable;
    flags: (0x0000) 
    Code:
      stack=2, locals=6, args_size=2
        start local 0 // com.oracle.truffle.api.TruffleFile$FileSystemContext this
        start local 1 // java.util.Set mimeTypes
         0: .line 2063
            aload 0 /* this */
            getfield com.oracle.truffle.api.TruffleFile$FileSystemContext.fileTypeDetectors:Ljava/util/Map;
            astore 2 /* result */
        start local 2 // java.util.Map result
         1: .line 2064
            aload 2 /* result */
            ifnonnull 5
         2: .line 2065
            invokestatic com.oracle.truffle.api.LanguageAccessor.engineAccess:()Lcom/oracle/truffle/api/impl/Accessor$EngineSupport;
            aload 0 /* this */
            getfield com.oracle.truffle.api.TruffleFile$FileSystemContext.engineObject:Ljava/lang/Object;
            invokevirtual com.oracle.truffle.api.impl.Accessor$EngineSupport.getEngineFileTypeDetectors:(Ljava/lang/Object;)Ljava/util/Map;
            astore 2 /* result */
         3: .line 2066
            getstatic com.oracle.truffle.api.TruffleFile$FileSystemContext.$assertionsDisabled:Z
            ifne 4
            aload 2 /* result */
            ifnonnull 4
            new java.lang.AssertionError
            dup
            invokespecial java.lang.AssertionError.<init>:()V
            athrow
         4: .line 2067
      StackMap locals: java.util.Map
      StackMap stack:
            aload 0 /* this */
            aload 2 /* result */
            putfield com.oracle.truffle.api.TruffleFile$FileSystemContext.fileTypeDetectors:Ljava/util/Map;
         5: .line 2069
      StackMap locals:
      StackMap stack:
            new java.util.HashSet
            dup
            invokespecial java.util.HashSet.<init>:()V
            astore 3 /* filtered */
        start local 3 // java.util.Set filtered
         6: .line 2070
            aload 2 /* result */
            invokeinterface java.util.Map.entrySet:()Ljava/util/Set;
            invokeinterface java.util.Set.iterator:()Ljava/util/Iterator;
            astore 5
            goto 10
      StackMap locals: com.oracle.truffle.api.TruffleFile$FileSystemContext java.util.Set java.util.Map java.util.Set top java.util.Iterator
      StackMap stack:
         7: aload 5
            invokeinterface java.util.Iterator.next:()Ljava/lang/Object;
            checkcast java.util.Map$Entry
            astore 4 /* e */
        start local 4 // java.util.Map$Entry e
         8: .line 2071
            aload 1 /* mimeTypes */
            ifnull 9
            aload 1 /* mimeTypes */
            aload 4 /* e */
            invokeinterface java.util.Map$Entry.getKey:()Ljava/lang/Object;
            invokeinterface java.util.Set.contains:(Ljava/lang/Object;)Z
            ifeq 10
         9: .line 2072
      StackMap locals: com.oracle.truffle.api.TruffleFile$FileSystemContext java.util.Set java.util.Map java.util.Set java.util.Map$Entry java.util.Iterator
      StackMap stack:
            aload 3 /* filtered */
            aload 4 /* e */
            invokeinterface java.util.Map$Entry.getValue:()Ljava/lang/Object;
            checkcast java.util.Collection
            invokeinterface java.util.Set.addAll:(Ljava/util/Collection;)Z
            pop
        end local 4 // java.util.Map$Entry e
        10: .line 2070
      StackMap locals: com.oracle.truffle.api.TruffleFile$FileSystemContext java.util.Set java.util.Map java.util.Set top java.util.Iterator
      StackMap stack:
            aload 5
            invokeinterface java.util.Iterator.hasNext:()Z
            ifne 7
        11: .line 2075
            aload 3 /* filtered */
            areturn
        end local 3 // java.util.Set filtered
        end local 2 // java.util.Map result
        end local 1 // java.util.Set mimeTypes
        end local 0 // com.oracle.truffle.api.TruffleFile$FileSystemContext this
      LocalVariableTable:
        Start  End  Slot       Name  Signature
            0   12     0       this  Lcom/oracle/truffle/api/TruffleFile$FileSystemContext;
            0   12     1  mimeTypes  Ljava/util/Set<Ljava/lang/String;>;
            1   12     2     result  Ljava/util/Map<Ljava/lang/String;Ljava/util/Collection<+Lcom/oracle/truffle/api/TruffleFile$FileTypeDetector;>;>;
            6   12     3   filtered  Ljava/util/Set<Lcom/oracle/truffle/api/TruffleFile$FileTypeDetector;>;
            8   10     4          e  Ljava/util/Map$Entry<Ljava/lang/String;Ljava/util/Collection<+Lcom/oracle/truffle/api/TruffleFile$FileTypeDetector;>;>;
    Signature: (Ljava/util/Set<Ljava/lang/String;>;)Ljava/lang/Iterable<+Lcom/oracle/truffle/api/TruffleFile$FileTypeDetector;>;
    MethodParameters:
           Name  Flags
      mimeTypes  
}
SourceFile: "TruffleFile.java"
NestHost: com.oracle.truffle.api.TruffleFile
InnerClasses:
  final FileSystemContext = com.oracle.truffle.api.TruffleFile$FileSystemContext of com.oracle.truffle.api.TruffleFile
  public abstract FileTypeDetector = com.oracle.truffle.api.TruffleFile$FileTypeDetector of com.oracle.truffle.api.TruffleFile
  public abstract EngineSupport = com.oracle.truffle.api.impl.Accessor$EngineSupport of com.oracle.truffle.api.impl.Accessor
  public abstract Entry = java.util.Map$Entry of java.util.Map