https://www.graalvm.org/ 
class com.oracle.truffle.api.instrumentation.TruffleInstrument$Env$MessageTransportProxy implements org.graalvm.polyglot.io.MessageTransport
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.oracle.truffle.api.instrumentation.TruffleInstrument$Env$MessageTransportProxy
  super_class: java.lang.Object
{
  private final org.graalvm.polyglot.io.MessageTransport transport;
    descriptor: Lorg/graalvm/polyglot/io/MessageTransport;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  void <init>(org.graalvm.polyglot.io.MessageTransport);
    descriptor: (Lorg/graalvm/polyglot/io/MessageTransport;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.oracle.truffle.api.instrumentation.TruffleInstrument$Env$MessageTransportProxy this
        start local 1 // org.graalvm.polyglot.io.MessageTransport transport
         0: .line 1268
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 1269
            aload 0 /* this */
            aload 1 /* transport */
            putfield com.oracle.truffle.api.instrumentation.TruffleInstrument$Env$MessageTransportProxy.transport:Lorg/graalvm/polyglot/io/MessageTransport;
         2: .line 1270
            return
        end local 1 // org.graalvm.polyglot.io.MessageTransport transport
        end local 0 // com.oracle.truffle.api.instrumentation.TruffleInstrument$Env$MessageTransportProxy this
      LocalVariableTable:
        Start  End  Slot       Name  Signature
            0    3     0       this  Lcom/oracle/truffle/api/instrumentation/TruffleInstrument$Env$MessageTransportProxy;
            0    3     1  transport  Lorg/graalvm/polyglot/io/MessageTransport;
    MethodParameters:
           Name  Flags
      transport  

  public org.graalvm.polyglot.io.MessageEndpoint open(java.net.URI, org.graalvm.polyglot.io.MessageEndpoint);
    descriptor: (Ljava/net/URI;Lorg/graalvm/polyglot/io/MessageEndpoint;)Lorg/graalvm/polyglot/io/MessageEndpoint;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=5, locals=4, args_size=3
        start local 0 // com.oracle.truffle.api.instrumentation.TruffleInstrument$Env$MessageTransportProxy this
        start local 1 // java.net.URI uri
        start local 2 // org.graalvm.polyglot.io.MessageEndpoint peerEndpoint
         0: .line 1274
            aload 2 /* peerEndpoint */
            ldc "The peer endpoint must be non null."
            invokestatic java.util.Objects.requireNonNull:(Ljava/lang/Object;Ljava/lang/String;)Ljava/lang/Object;
            pop
         1: .line 1275
            aload 0 /* this */
            getfield com.oracle.truffle.api.instrumentation.TruffleInstrument$Env$MessageTransportProxy.transport:Lorg/graalvm/polyglot/io/MessageTransport;
            aload 1 /* uri */
            new com.oracle.truffle.api.instrumentation.TruffleInstrument$Env$MessageTransportProxy$MessageEndpointProxy
            dup
            aload 2 /* peerEndpoint */
            invokespecial com.oracle.truffle.api.instrumentation.TruffleInstrument$Env$MessageTransportProxy$MessageEndpointProxy.<init>:(Lorg/graalvm/polyglot/io/MessageEndpoint;)V
            invokeinterface org.graalvm.polyglot.io.MessageTransport.open:(Ljava/net/URI;Lorg/graalvm/polyglot/io/MessageEndpoint;)Lorg/graalvm/polyglot/io/MessageEndpoint;
            astore 3 /* openedEndpoint */
        start local 3 // org.graalvm.polyglot.io.MessageEndpoint openedEndpoint
         2: .line 1276
            aload 3 /* openedEndpoint */
            ifnonnull 4
         3: .line 1277
            aconst_null
            areturn
         4: .line 1279
      StackMap locals: org.graalvm.polyglot.io.MessageEndpoint
      StackMap stack:
            new com.oracle.truffle.api.instrumentation.TruffleInstrument$Env$MessageTransportProxy$MessageEndpointProxy
            dup
            aload 3 /* openedEndpoint */
            invokespecial com.oracle.truffle.api.instrumentation.TruffleInstrument$Env$MessageTransportProxy$MessageEndpointProxy.<init>:(Lorg/graalvm/polyglot/io/MessageEndpoint;)V
            areturn
        end local 3 // org.graalvm.polyglot.io.MessageEndpoint openedEndpoint
        end local 2 // org.graalvm.polyglot.io.MessageEndpoint peerEndpoint
        end local 1 // java.net.URI uri
        end local 0 // com.oracle.truffle.api.instrumentation.TruffleInstrument$Env$MessageTransportProxy this
      LocalVariableTable:
        Start  End  Slot            Name  Signature
            0    5     0            this  Lcom/oracle/truffle/api/instrumentation/TruffleInstrument$Env$MessageTransportProxy;
            0    5     1             uri  Ljava/net/URI;
            0    5     2    peerEndpoint  Lorg/graalvm/polyglot/io/MessageEndpoint;
            2    5     3  openedEndpoint  Lorg/graalvm/polyglot/io/MessageEndpoint;
    Exceptions:
      throws java.io.IOException, org.graalvm.polyglot.io.MessageTransport$VetoException
    MethodParameters:
              Name  Flags
      uri           
      peerEndpoint  
}
SourceFile: "TruffleInstrument.java"
NestHost: com.oracle.truffle.api.instrumentation.TruffleInstrument
InnerClasses:
  public final Env = com.oracle.truffle.api.instrumentation.TruffleInstrument$Env of com.oracle.truffle.api.instrumentation.TruffleInstrument
  private MessageTransportProxy = com.oracle.truffle.api.instrumentation.TruffleInstrument$Env$MessageTransportProxy of com.oracle.truffle.api.instrumentation.TruffleInstrument$Env
  private MessageEndpointProxy = com.oracle.truffle.api.instrumentation.TruffleInstrument$Env$MessageTransportProxy$MessageEndpointProxy of com.oracle.truffle.api.instrumentation.TruffleInstrument$Env$MessageTransportProxy
  public final VetoException = org.graalvm.polyglot.io.MessageTransport$VetoException of org.graalvm.polyglot.io.MessageTransport