java day lviv - spring boot under the hood

SPRING BOOT UNDER THE HOOD@NICOLAS_FRANKEL

@nicolas_frankel #springboot 2

ME, MYSELF AND I Developer/Software

-/Solution Architect• Java• As consultant


HYBRIS, AN SAP COMPANY

4@nicolas_frankel #springboot


SPRING BOOT ACTUATOR<dependency> <groupId> org.springframework.boot </groupId> <artifactId> spring-boot-starter-actuator </artifactId></dependency>


/HEALTH{ "status" : "UP", "diskSpace" : { "status" : "UP", "total" : 499055067136, "free" : 254812135424, "threshold" : 10485760 }, "db" : { "status" : "UP", "database" : "HSQL Database Engine", "hello" : 1 } }


SPRING BOOTWorks well until:• It doesn’t anymore•Or you want to change the

default behavior


CONFIGURATION – POM.XML<dependency> <groupId> org.springframework.boot </groupId> <artifactId> spring-boot-starter-data-jpa </artifactId></dependency><dependency> <groupId>org.hsqldb</groupId> <artifactId>hsqldb</artifactId> <scope>runtime</scope></dependency>


LET’S CHECK HOW IT WORKS


STARTERS DEPENDENCIES


SPRING-BOOT-AUTOCONFIGURE.JAR


SPRING.FACTORIES


@JPAREPOSITORIESAUTOCONFIGURATION@Configuration@ConditionalOnBean(DataSource.class)@ConditionalOnClass(JpaRepository.class)@ConditionalOnMissingBean({ JpaRepositoryFactoryBean.class, JpaRepositoryConfigExtension.class })@ConditionalOnProperty( prefix = "spring.data.jpa.repositories", name = "enabled", havingValue = "true", matchIfMissing = true)@Import(JpaRepositoriesAutoConfigureRegistrar.class)@AutoConfigureAfter( HibernateJpaAutoConfiguration.class)public class JpaRepositoriesAutoConfiguration {

}


@CONDITIONAL@ConditionalOnBean@ConditionalOnClass@ConditionalOnMissingBean@ConditionalOnPropertyetc.


REMEMBER @PROFILE?@Retention(RetentionPolicy.RUNTIME)@Target(ElementType.TYPE)public @interface Profile {

String[] value();}


THIS IS THE NEW @PROFILE@Retention(RetentionPolicy.RUNTIME)@Target({ElementType.TYPE, ElementType.METHOD})@Documented@Conditional(ProfileCondition.class)public @interface Profile {

String[] value();}


@CONDITIONAL & CONDITION


@CONDITIONAL & CONDITIONEnables calling of a @Bean-annotated method• In the context of a

@Configuration class


ENOUGH TALK…

Time for DEMO


OUT-OF-THE-BOX CONDITIONSCondition DescriptionOnBeanCondition Checks if a bean is in the Spring factoryOnClassCondition Checks if a class is on the classpathOnExpressionCondition Evalutates a SPeL expressionOnJavaCondition Checks the version of JavaOnJndiCondition Checks if a JNDI branch existsOnPropertyCondition Checks if a property existsOnResourceCondition Checks if a resource existsOnWebApplicationCondition Checks if a WebApplicationContext exists


COMPOSITE CONDITIONSCondition DescriptionAllNestedConditions AND conditionAnyNestedConditions OR conditionNoneNestedCondition NOT condition


OUR OWN STARTER

Time for DEMO


Q&A

http://blog.frankel.ch/@nicolas_frankel http://frankel.in/https://git.io/v2f3O