https://spring.io/projects/spring-boot: Spring Boot (Pivotal Software, Inc.) 
public interface org.springframework.boot.context.properties.PropertyMapper$SourceOperator
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: org.springframework.boot.context.properties.PropertyMapper$SourceOperator
  super_class: java.lang.Object
{
  public abstract <T> org.springframework.boot.context.properties.PropertyMapper$Source<T> apply(org.springframework.boot.context.properties.PropertyMapper$Source<T>);
    descriptor: (Lorg/springframework/boot/context/properties/PropertyMapper$Source;)Lorg/springframework/boot/context/properties/PropertyMapper$Source;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    Signature: <T:Ljava/lang/Object;>(Lorg/springframework/boot/context/properties/PropertyMapper$Source<TT;>;)Lorg/springframework/boot/context/properties/PropertyMapper$Source<TT;>;
    MethodParameters:
        Name  Flags
      source  
}
SourceFile: "PropertyMapper.java"
NestHost: org.springframework.boot.context.properties.PropertyMapper
InnerClasses:
  public final Source = org.springframework.boot.context.properties.PropertyMapper$Source of org.springframework.boot.context.properties.PropertyMapper
  public abstract SourceOperator = org.springframework.boot.context.properties.PropertyMapper$SourceOperator of org.springframework.boot.context.properties.PropertyMapper
    RuntimeVisibleAnnotations: 
      java.lang.FunctionalInterface()