Mapper Type — spring-boot Architecture

Source Code

core/spring-boot/src/main/java/org/springframework/boot/context/properties/PropertyMapper.java lines 543–554

			@FunctionalInterface
			public interface Mapper<R extends @Nullable Object, T> {

				/**
				 * Map a existing instance for the given nullable value.
				 * @param instance the existing instance
				 * @param value the value to map (may be {@code null})
				 * @return the resulting mapped instance
				 */
				R map(R instance, @Nullable T value);

			}