https://openjdk.java.net/ 
public interface sun.tools.jstat.OutputFormatter
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: sun.tools.jstat.OutputFormatter
  super_class: java.lang.Object
{
  public abstract java.lang.String getHeader();
    descriptor: ()Ljava/lang/String;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    Exceptions:
      throws sun.jvmstat.monitor.MonitorException

  public abstract java.lang.String getRow();
    descriptor: ()Ljava/lang/String;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    Exceptions:
      throws sun.jvmstat.monitor.MonitorException
}
SourceFile: "OutputFormatter.java"