Keeping Your Data Sane with Bean Validation 2.0 Gunnar Morling, Red Hat 1 

Agenda What is Bean Validation? What's new in Bean Validation 2.0? Questions, feedback 2 

Gunnar Morling Open source software engineer at Red Hat Hibernate Debezium Spec Lead for Bean Validation 2.0 Other projects: ModiTect, MapStruct [email protected] @gunnarmorling http://in.relation.to/gunnar-morling/ 3 

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 

Demo 5 

Bean Validation 2.0 - JSR 380 Benefit from new language features Support for API extensions 6 

Repeatable Annotations @Size.List({ @Size(min = 8, group = Default.class), @Size(min = 12, group = Admin.class) }) private char[] password = ...; 7 

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 

Collection Validation private List names; 9 

Collection Validation private List names; @Size(max=10) private List names; 10 

Collection Validation private List names; @Size(max=10) private List<@Pattern(regexp="[a-zA-Z]*") String> names; @Size(max=10) private List names; 11 

Collection Validation private List 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 names; 12 

@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 

Cascaded Validation @Valid private List

addresses; 14 

Cascaded Validation @Valid private List

addresses; private List<@Valid Address> addresses; 15 

Cascaded Validation @Valid private List

addresses; private List<@Valid Address> addresses; private Map<@Valid Comment, @Min(0) @Max(5) Integer> scorePerComment; 16 

java.util.Optional Neuer ElementType TYPE Also for StringProperty et al. (JavaFX) Optional<@Email String> getEmail() { ... }; 17 

Custom Containers Specific collection types (e.g. Google Guava) Other JVM languages (Ceylon, Scala etc.) Enabled via Extractor SPI private Table revenuePerYearAndCategory; 18 

private Table revenuePerYearAndCategory; private Table revenuePerYearAndCategory; Custom Containers Specific collection types (e.g. Google Guava) Other JVM languages (Ceylon, Scala etc.) Enabled via Extractor SPI 19 

Demo 20.1 

class TableValueExtractor implements ValueExtractor> { @Override public void extractValues(Table originalValue, ValueExtractor.ValueReceiver receiver) { for ( Cell cell : originalValue.cellSet() ) { receiver.keyedValue( "", new CellKey( cell.getRowKey(), cell.getColumnKey() ), cell.getValue() ); } } } 20.2 

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 

@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 

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 

Other Java 8 Goodies ConstraintValidator without initialize() public class NotNullValidator implements ConstraintValidator { public void initialize(NotNull constraintAnnotation) { } public boolean isValid(Object object, ConstraintValidatorContext ctx) { return object != null; } } public class NotNullValidator implements ConstraintValidator { public boolean isValid(Object object, ConstraintValidatorContext ctx) { return object != null; } } 24 

Some More Improvements New constraints @NotEmpty, @NotBlank @Email @Positive, @Negative ValidatorFactory implements AutoCloseable try ( ValidatorFactory vf = Validation.buildDefaultValidatorFactory() ) { } 25 

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 

Status Spec: Public Review Reference implementation: Hibernate Validator 6.0 Beta1 Your feedback is needed :-) Part of Java EE 8 (July 2017) 27 

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 

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