https://openjdk.java.net/ 
public interface sun.jvm.hotspot.utilities.HeapGraphWriter
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: sun.jvm.hotspot.utilities.HeapGraphWriter
  super_class: java.lang.Object
{
  public abstract void write(java.lang.String);
    descriptor: (Ljava/lang/String;)V
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    Exceptions:
      throws java.io.IOException
    MethodParameters:
          Name  Flags
      fileName  
}
SourceFile: "HeapGraphWriter.java"