https://www.graalvm.org/ 
class com.oracle.truffle.js.shell.JSFuzzilliRunner$1 extends java.util.TimerTask
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.oracle.truffle.js.shell.JSFuzzilliRunner$1
  super_class: java.util.TimerTask
{
  private final org.graalvm.polyglot.Context val$context;
    descriptor: Lorg/graalvm/polyglot/Context;
    flags: (0x1012) ACC_PRIVATE, ACC_FINAL, ACC_SYNTHETIC

  void <init>(org.graalvm.polyglot.Context);
    descriptor: (Lorg/graalvm/polyglot/Context;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.oracle.truffle.js.shell.JSFuzzilliRunner$1 this
         0: .line 124
            aload 0 /* this */
            aload 1
            putfield com.oracle.truffle.js.shell.JSFuzzilliRunner$1.val$context:Lorg/graalvm/polyglot/Context;
            aload 0 /* this */
            invokespecial java.util.TimerTask.<init>:()V
            return
        end local 0 // com.oracle.truffle.js.shell.JSFuzzilliRunner$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/js/shell/JSFuzzilliRunner$1;
    MethodParameters:
             Name  Flags
      val$context  final

  public void run();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=1, args_size=1
        start local 0 // com.oracle.truffle.js.shell.JSFuzzilliRunner$1 this
         0: .line 127
            aload 0 /* this */
            getfield com.oracle.truffle.js.shell.JSFuzzilliRunner$1.val$context:Lorg/graalvm/polyglot/Context;
            iconst_1
            invokevirtual org.graalvm.polyglot.Context.close:(Z)V
         1: .line 128
            return
        end local 0 // com.oracle.truffle.js.shell.JSFuzzilliRunner$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    2     0  this  Lcom/oracle/truffle/js/shell/JSFuzzilliRunner$1;
}
SourceFile: "JSFuzzilliRunner.java"
EnclosingMethod: com.oracle.truffle.js.shell.JSFuzzilliRunner.runFuzzilliREPRL:(Lorg/graalvm/polyglot/Context$Builder;)I
NestHost: com.oracle.truffle.js.shell.JSFuzzilliRunner
InnerClasses:
  com.oracle.truffle.js.shell.JSFuzzilliRunner$1
  public final Builder = org.graalvm.polyglot.Context$Builder of org.graalvm.polyglot.Context