https://www.graalvm.org/ 
public final class com.oracle.truffle.trufflenode.buffer.NIOBuffer extends com.oracle.truffle.js.runtime.builtins.JSNonProxy
  minor version: 0
  major version: 59
  flags: flags: (0x0031) ACC_PUBLIC, ACC_FINAL, ACC_SUPER
  this_class: com.oracle.truffle.trufflenode.buffer.NIOBuffer
  super_class: com.oracle.truffle.js.runtime.builtins.JSNonProxy
{
  private static final com.oracle.truffle.js.builtins.JSBuiltinsContainer NIO_BUFFER_BUILTINS;
    descriptor: Lcom/oracle/truffle/js/builtins/JSBuiltinsContainer;
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL

  public static final java.lang.String NIO_BUFFER_MODULE_NAME;
    descriptor: Ljava/lang/String;
    flags: (0x0019) ACC_PUBLIC, ACC_STATIC, ACC_FINAL
    ConstantValue: "internal/graal/buffer.js"

  private static final java.lang.String CLASS_NAME;
    descriptor: Ljava/lang/String;
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL
    ConstantValue: "NIOBuffer"

  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=2, locals=0, args_size=0
         0: .line 59
            ldc Lcom/oracle/truffle/trufflenode/buffer/NIOBuffer;
            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.trufflenode.buffer.NIOBuffer.$assertionsDisabled:Z
         3: .line 60
            new com.oracle.truffle.trufflenode.buffer.NIOBufferBuiltins
            dup
            invokespecial com.oracle.truffle.trufflenode.buffer.NIOBufferBuiltins.<init>:()V
            putstatic com.oracle.truffle.trufflenode.buffer.NIOBuffer.NIO_BUFFER_BUILTINS:Lcom/oracle/truffle/js/builtins/JSBuiltinsContainer;
         4: .line 64
            return
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  private void <init>();
    descriptor: ()V
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.oracle.truffle.trufflenode.buffer.NIOBuffer this
         0: .line 66
            aload 0 /* this */
            invokespecial com.oracle.truffle.js.runtime.builtins.JSNonProxy.<init>:()V
         1: .line 67
            return
        end local 0 // com.oracle.truffle.trufflenode.buffer.NIOBuffer this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    2     0  this  Lcom/oracle/truffle/trufflenode/buffer/NIOBuffer;

  private static com.oracle.truffle.api.object.DynamicObject create(com.oracle.truffle.js.runtime.JSContext);
    descriptor: (Lcom/oracle/truffle/js/runtime/JSContext;)Lcom/oracle/truffle/api/object/DynamicObject;
    flags: (0x000a) ACC_PRIVATE, ACC_STATIC
    Code:
      stack=3, locals=2, args_size=1
        start local 0 // com.oracle.truffle.js.runtime.JSContext context
         0: .line 71
            aload 0 /* context */
            invokestatic com.oracle.truffle.js.runtime.builtins.JSOrdinary.createWithNullPrototype:(Lcom/oracle/truffle/js/runtime/JSContext;)Lcom/oracle/truffle/api/object/DynamicObject;
            astore 1 /* obj */
        start local 1 // com.oracle.truffle.api.object.DynamicObject obj
         1: .line 72
            aload 0 /* context */
            invokevirtual com.oracle.truffle.js.runtime.JSContext.getRealm:()Lcom/oracle/truffle/js/runtime/JSRealm;
            aload 1 /* obj */
            getstatic com.oracle.truffle.trufflenode.buffer.NIOBuffer.NIO_BUFFER_BUILTINS:Lcom/oracle/truffle/js/builtins/JSBuiltinsContainer;
            invokestatic com.oracle.truffle.js.runtime.objects.JSObjectUtil.putFunctionsFromContainer:(Lcom/oracle/truffle/js/runtime/JSRealm;Lcom/oracle/truffle/api/object/DynamicObject;Lcom/oracle/truffle/js/builtins/JSBuiltinsContainer;)V
         2: .line 73
            aload 1 /* obj */
            areturn
        end local 1 // com.oracle.truffle.api.object.DynamicObject obj
        end local 0 // com.oracle.truffle.js.runtime.JSContext context
      LocalVariableTable:
        Start  End  Slot     Name  Signature
            0    3     0  context  Lcom/oracle/truffle/js/runtime/JSContext;
            1    3     1      obj  Lcom/oracle/truffle/api/object/DynamicObject;
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.CompilerDirectives$TruffleBoundary()
    MethodParameters:
         Name  Flags
      context  

  public java.lang.String getClassName(com.oracle.truffle.api.object.DynamicObject);
    descriptor: (Lcom/oracle/truffle/api/object/DynamicObject;)Ljava/lang/String;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=2, args_size=2
        start local 0 // com.oracle.truffle.trufflenode.buffer.NIOBuffer this
        start local 1 // com.oracle.truffle.api.object.DynamicObject object
         0: .line 78
            ldc "NIOBuffer"
            areturn
        end local 1 // com.oracle.truffle.api.object.DynamicObject object
        end local 0 // com.oracle.truffle.trufflenode.buffer.NIOBuffer this
      LocalVariableTable:
        Start  End  Slot    Name  Signature
            0    1     0    this  Lcom/oracle/truffle/trufflenode/buffer/NIOBuffer;
            0    1     1  object  Lcom/oracle/truffle/api/object/DynamicObject;
    MethodParameters:
        Name  Flags
      object  

  public static java.lang.Object createInitFunction(com.oracle.truffle.js.runtime.JSContext);
    descriptor: (Lcom/oracle/truffle/js/runtime/JSContext;)Ljava/lang/Object;
    flags: (0x0009) ACC_PUBLIC, ACC_STATIC
    Code:
      stack=4, locals=4, args_size=1
        start local 0 // com.oracle.truffle.js.runtime.JSContext context
         0: .line 83
            aload 0 /* context */
            invokevirtual com.oracle.truffle.js.runtime.JSContext.getRealm:()Lcom/oracle/truffle/js/runtime/JSRealm;
            astore 1 /* realm */
        start local 1 // com.oracle.truffle.js.runtime.JSRealm realm
         1: .line 87
            new com.oracle.truffle.trufflenode.buffer.NIOBuffer$1
            dup
            aload 0 /* context */
            invokespecial com.oracle.truffle.trufflenode.buffer.NIOBuffer$1.<init>:(Lcom/oracle/truffle/js/runtime/JSContext;)V
            astore 2 /* wrapperNode */
        start local 2 // com.oracle.truffle.js.runtime.JavaScriptRootNode wrapperNode
         2: .line 100
            aload 0 /* context */
            invokestatic com.oracle.truffle.api.Truffle.getRuntime:()Lcom/oracle/truffle/api/TruffleRuntime;
            aload 2 /* wrapperNode */
            invokeinterface com.oracle.truffle.api.TruffleRuntime.createCallTarget:(Lcom/oracle/truffle/api/nodes/RootNode;)Lcom/oracle/truffle/api/RootCallTarget;
            iconst_2
            ldc "NIOBufferBuiltinsInitFunction"
            invokestatic com.oracle.truffle.js.runtime.builtins.JSFunctionData.createCallOnly:(Lcom/oracle/truffle/js/runtime/JSContext;Lcom/oracle/truffle/api/CallTarget;ILjava/lang/String;)Lcom/oracle/truffle/js/runtime/builtins/JSFunctionData;
            astore 3 /* functionData */
        start local 3 // com.oracle.truffle.js.runtime.builtins.JSFunctionData functionData
         3: .line 101
            aload 1 /* realm */
            aload 3 /* functionData */
            invokestatic com.oracle.truffle.js.runtime.builtins.JSFunction.create:(Lcom/oracle/truffle/js/runtime/JSRealm;Lcom/oracle/truffle/js/runtime/builtins/JSFunctionData;)Lcom/oracle/truffle/api/object/DynamicObject;
            areturn
        end local 3 // com.oracle.truffle.js.runtime.builtins.JSFunctionData functionData
        end local 2 // com.oracle.truffle.js.runtime.JavaScriptRootNode wrapperNode
        end local 1 // com.oracle.truffle.js.runtime.JSRealm realm
        end local 0 // com.oracle.truffle.js.runtime.JSContext context
      LocalVariableTable:
        Start  End  Slot          Name  Signature
            0    4     0       context  Lcom/oracle/truffle/js/runtime/JSContext;
            1    4     1         realm  Lcom/oracle/truffle/js/runtime/JSRealm;
            2    4     2   wrapperNode  Lcom/oracle/truffle/js/runtime/JavaScriptRootNode;
            3    4     3  functionData  Lcom/oracle/truffle/js/runtime/builtins/JSFunctionData;
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.CompilerDirectives$TruffleBoundary()
    MethodParameters:
         Name  Flags
      context  
}
SourceFile: "NIOBuffer.java"
NestMembers:
  com.oracle.truffle.trufflenode.buffer.NIOBuffer$1
InnerClasses:
  public abstract TruffleBoundary = com.oracle.truffle.api.CompilerDirectives$TruffleBoundary of com.oracle.truffle.api.CompilerDirectives
  com.oracle.truffle.trufflenode.buffer.NIOBuffer$1