https://openjdk.java.net/ 
public interface jdk.nashorn.api.tree.WhileLoopTree extends jdk.nashorn.api.tree.ConditionalLoopTree
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: jdk.nashorn.api.tree.WhileLoopTree
  super_class: java.lang.Object
{
  public abstract jdk.nashorn.api.tree.ExpressionTree getCondition();
    descriptor: ()Ljdk/nashorn/api/tree/ExpressionTree;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public abstract jdk.nashorn.api.tree.StatementTree getStatement();
    descriptor: ()Ljdk/nashorn/api/tree/StatementTree;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
}
SourceFile: "WhileLoopTree.java"