Keeping Your Data Sane with Bean Validation 2.0

Rich UIs, schemaless datastores, microservices communicating with each other - the need for powerful and easy-to-use data validation services has never been bigger.

The Bean Validation standard is here to help, providing Java developers with a rich validation API based on annotations. Bean Validation 2.0 (JSR 380) takes validation to the next level by leveraging Java 8 features such as lambdas, additional annotation locations and repeatable annotations. This opens up exciting opportunities for Bean Validation - e.g. List<@Email String>. There will also be support for Optional, the java.time API and more.

Join us and see what's planned for Bean Validation 2.0 and what's already done. Like its predecessors, JSR 380 is developed fully in the open: come exchange, propose and participate!

Presentation given at RivieraDev 2017

Transcript

1. Keeping Your Data Sane with Bean Validation 2.0 Gunnar Morling, Red Hat 1
2. Agenda What is Bean Validation? What's new in Bean Validation 2.0? Questions, feedback 2
3. Gunnar Morling Open source software engineer at Red Hat Hibernate Debezium Spec Lead for Bean Validation 2.0 Other projects: ModiTect, MapStruct gunnar@hibernate.org @gunnarmorling http://in.relation.to/gunnar-morling/ 3
4. What is Bean Validation? "Constraint once, validate everywhere" Constraints for JavaBeans Validation via API or automatically ​ JPA JSF, Spring MVC, GWT JAX-RS Extensible (custom constraints) BV 1.1: ​ method validation 4
5. Demo 5
6. Bean Validation 2.0 - JSR 380 Benefit from new language features Support for API extensions 6
7. Repeatable Annotations @Size.List({ @Size(min = 8, group = Default.class), @Size(min = 12, group = Admin.class) }) private char[] password = ...; 7
8. Repeatable Annotations @Size.List({ @Size(min = 8, group = Default.class), @Size(min = 12, group = Admin.class) }) private char[] password = ...; @Size(min = 8, group = Default.class) @Size(min = 12, group = Admin.class) private char[] password = ...; 8
9. Collection Validation private List<String> names; 9
10. Collection Validation private List<String> names; @Size(max=10) private List<String> names; 10
11. Collection Validation private List<String> names; @Size(max=10) private List<@Pattern(regexp="[a-zA-Z]*") String> names; @Size(max=10) private List<String> names; 11
12. Collection Validation private List<String> names; @Size(max=10) private List<@Size(max=50) String> names; @Size(max=10) private List<@Pattern(regexp="[a-zA-Z]*") String> names; @Size(max=10) private List<String> names; 12
13. @Target({ METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER, TYPE_USE }) @Retention(RUNTIME) @Repeatable(List.class) @Documented @Constraint(validatedBy = { }) public @interface Size { ... } Type Annotations (JSR 308) New element type TYPE_USE 13
14. Cascaded Validation @Valid private List<Address> addresses; 14
15. Cascaded Validation @Valid private List<Address> addresses; private List<@Valid Address> addresses; 15
16. Cascaded Validation @Valid private List<Address> addresses; private List<@Valid Address> addresses; private Map<@Valid Comment, @Min(0) @Max(5) Integer> scorePerComment; 16
17. java.util.Optional Neuer ElementType TYPE Also for StringProperty et al. (JavaFX) Optional<@Email String> getEmail() { ... }; 17
18. Custom Containers Specific collection types (e.g. Google Guava) Other JVM languages (Ceylon, Scala etc.) Enabled via Extractor SPI private Table<Year, String, Integer> revenuePerYearAndCategory; 18
19. private Table<Year, String, Integer> revenuePerYearAndCategory; private Table<Year, String, @Positive Integer> revenuePerYearAndCategory; Custom Containers Specific collection types (e.g. Google Guava) Other JVM languages (Ceylon, Scala etc.) Enabled via Extractor SPI 19
20. Demo 20.1
21. class TableValueExtractor implements ValueExtractor<Table<?, ?, @ExtractedValue ?>> { @Override public void extractValues(Table<?, ?, ?> originalValue, ValueExtractor.ValueReceiver receiver) { for ( Cell<?, ?, ?> cell : originalValue.cellSet() ) { receiver.keyedValue( "<table cell>", new CellKey( cell.getRowKey(), cell.getColumnKey() ), cell.getValue() ); } } } 20.2
22. java.time API (JSR 310) @Past/@Future supported for java.time.LocalDateTime, ZonedDateTime etc. @Future private LocalDate deliveryDate = LocalDate.of( 2017, Month.MAY, 12 ); 21
23. @Future private LocalDate deliveryDate = LocalDate.of( 2017, Month.MAY, 12 ); java.time API (JSR 310) @Past/@Future supported for java.time.LocalDateTime, ZonedDateTime etc. @Future(orPresent=true) private LocalDate deliveryDate = LocalDate.of( 2017, Month.MAY, 12 ); 22
24. java.time API (JSR 310) ValidatorFactory vf = Validation.byDefaultProvider() .configure() .clockProvider( new FixedClockProvider( ZonedDateTime.of( 2016, 6, 15, 0, 0, 0, 0, ZoneId.of( "Europe/Paris" ) ) ) ) .buildValidatorFactory(); 23
25. Other Java 8 Goodies ConstraintValidator without initialize() public class NotNullValidator implements ConstraintValidator<NotNull, Object> { public void initialize(NotNull constraintAnnotation) { } public boolean isValid(Object object, ConstraintValidatorContext ctx) { return object != null; } } public class NotNullValidator implements ConstraintValidator<NotNull, Object> { public boolean isValid(Object object, ConstraintValidatorContext ctx) { return object != null; } } 24
26. Some More Improvements New constraints @NotEmpty, @NotBlank @Email @Positive, @Negative ValidatorFactory implements AutoCloseable try ( ValidatorFactory vf = Validation.buildDefaultValidatorFactory() ) { } 25
27. JSF 2.3 and JAX-RS 2.1 JSF: Validation of class level constraints JAX-RS Consider Request Locale Option for disabling Bean Validation 26
28. Status Spec: Public Review Reference implementation: Hibernate Validator 6.0 Beta1 Your feedback is needed :-) Part of Java EE 8 (July 2017) 27
29. Resources How to Contribute? API, specifikation, TCK, website Reference implementation Everything is open source (Apache License 2.0) beanvalidation.org/contribute/ github.com/beanvalidation/ github.com/hibernate/hibernate-validator/ 28