Using MyBatis I have created the mappers (Java interface + XML):
JAVA INTERFACE:
@Mapper
@Repository
@Primary
public interface DirezioneRegionaleMapper {
List<DirezioneRegionale> getAllDirRegs();
}
XML MAPPER:
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="com.listgroup.piu.dao.DirezioneRegionaleMapper">
<resultMap id="DirezioneRegionaleList" type="com.listgroup.piu.implementation.DirezioneRegionale">
<id column="ORG_LIV4_UO" jdbcType="NUMERIC" property="ID" />
<result column="ORG_LIV4_DES" jdbcType="VARCHAR" property="description" />
</resultMap>
<select id="getAllDirRegs" resultMap="DirezioneRegionaleList">
SELECT DISTINCT t.ORG_LIV4_UO, t.ORG_LIV4_DES
FROM DMM_DIM_STRUTTURA_ORG_HIS_GEN t
</select>
</mapper>
SERVICE CLASS:
@Service
@Transactional
public class DirezioneRegionaleService {
@Autowired
private DirezioneRegionaleMapper direzioneRegionaleMapper;
@Transactional(readOnly = true)
public List<DirezioneRegionale> getAllDirRegs() {
return this.direzioneRegionaleMapper.getAllDirRegs();
}
}
And the DirezioneRegionale class:
public class DirezioneRegionale {
private final int ID;
private final String description;
private List<DirezioneCommerciale> direzioniCommerciali;
public DirezioneRegionale(int ID, String description) {
this.ID = ID;
this.description = description;
this.direzioniCommerciali = null;
}
public void setDirezioniCommerciali(List<DirezioneCommerciale> direzioniCommerciali) {
this.direzioniCommerciali = direzioniCommerciali;
}
public int getID() {
return this.ID;
}
public String getDescription() {
return this.description;
}
public List<DirezioneCommerciale> getDirezioniCommerciali() {
return this.direzioniCommerciali;
}
}
I would like to do a thing like this: in my main I want to create an instance of the service class and then call the method "getAllDirRegs()", and I want to obtain a List, to do that I have created, as you can see, the resultMap in the XML file, but something does not work, because, when run the program, I have a NullPointerException.
This is my main:
public static void main(String[] args) {
SpringApplication.run(PiuApplication.class, args);
DirezioneRegionaleService service = new DirezioneRegionaleService();
List<DirezioneRegionale> dirRegs = service.getAllDirRegs();
System.out.println(dirRegs);
}
EDIT:
This is my stack trace:
java.lang.NullPointerException
at com.listgroup.piu.service.DirezioneRegionaleService.getAllDirRegs(DirezioneRegionaleService.java:20)
at com.listgroup.piu.PiuApplication.main(PiuApplication.java:28)
This is my log:
2020-02-25 21:08:27,687 INFO default [main] com.listgroup.piu.PiuApplication logStarting [StartupInfoLogger.java:48] Starting PiuApplication on IT586ADIMAGGI1L with PID 15572 (C:\Users\Antonino\Documents\isp.piuv2\target\classes started by Antonino in C:\Users\Antonino\Documents\isp.piuv2)
2020-02-25 21:08:27,689 DEBUG default [main] com.listgroup.piu.PiuApplication logStarting [StartupInfoLogger.java:51] Running with Spring Boot v1.5.19.RELEASE, Spring v4.3.22.RELEASE
2020-02-25 21:08:27,689 INFO default [main] com.listgroup.piu.PiuApplication logStartupProfileInfo [SpringApplication.java:597] The following profiles are active: dblistto
2020-02-25 21:08:27,717 INFO default [main] org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext prepareRefresh [AbstractApplicationContext.java:583] Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@5c33f1a9: startup date [Tue Feb 25 21:08:27 CET 2020]; root of context hierarchy
2020-02-25 21:08:27,776 INFO default [background-preinit] org.hibernate.validator.internal.util.Version <clinit> [Version.java:30] HV000001: Hibernate Validator 5.3.6.Final
2020-02-25 21:08:28,421 INFO default [main] org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainer initialize [TomcatEmbeddedServletContainer.java:92] Tomcat initialized with port(s): 8081 (http)
2020-02-25 21:08:28,428 INFO default [main] org.apache.coyote.http11.Http11NioProtocol log [DirectJDKLog.java:183] Initializing ProtocolHandler ["http-nio-8081"]
2020-02-25 21:08:28,431 INFO default [main] org.apache.catalina.core.StandardService log [DirectJDKLog.java:183] Starting service Tomcat
2020-02-25 21:08:28,431 INFO default [main] org.apache.catalina.core.StandardEngine log [DirectJDKLog.java:183] Starting Servlet Engine: Apache Tomcat/7.0.59
2020-02-25 21:08:28,519 INFO default [localhost-startStop-1] org.apache.catalina.core.ContainerBase.[Tomcat].[localhost].[/] log [DirectJDKLog.java:183] Initializing Spring embedded WebApplicationContext
2020-02-25 21:08:28,519 INFO default [localhost-startStop-1] org.springframework.web.context.ContextLoader prepareEmbeddedWebApplicationContext [EmbeddedWebApplicationContext.java:287] Root WebApplicationContext: initialization completed in 802 ms
2020-02-25 21:08:28,625 INFO default [localhost-startStop-1] org.springframework.boot.web.servlet.ServletRegistrationBean onStartup [ServletRegistrationBean.java:191] Mapping servlet: 'dispatcherServlet' to [/]
2020-02-25 21:08:28,626 INFO default [localhost-startStop-1] org.springframework.boot.web.servlet.FilterRegistrationBean configure [AbstractFilterRegistrationBean.java:259] Mapping filter: 'metricsFilter' to: [/*]
2020-02-25 21:08:28,626 INFO default [localhost-startStop-1] org.springframework.boot.web.servlet.FilterRegistrationBean configure [AbstractFilterRegistrationBean.java:259] Mapping filter: 'characterEncodingFilter' to: [/*]
2020-02-25 21:08:28,626 INFO default [localhost-startStop-1] org.springframework.boot.web.servlet.FilterRegistrationBean configure [AbstractFilterRegistrationBean.java:259] Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
2020-02-25 21:08:28,626 INFO default [localhost-startStop-1] org.springframework.boot.web.servlet.FilterRegistrationBean configure [AbstractFilterRegistrationBean.java:259] Mapping filter: 'httpPutFormContentFilter' to: [/*]
2020-02-25 21:08:28,626 INFO default [localhost-startStop-1] org.springframework.boot.web.servlet.FilterRegistrationBean configure [AbstractFilterRegistrationBean.java:259] Mapping filter: 'requestContextFilter' to: [/*]
2020-02-25 21:08:28,626 INFO default [localhost-startStop-1] org.springframework.boot.web.servlet.FilterRegistrationBean configure [AbstractFilterRegistrationBean.java:259] Mapping filter: 'webRequestLoggingFilter' to: [/*]
2020-02-25 21:08:28,626 INFO default [localhost-startStop-1] org.springframework.boot.web.servlet.FilterRegistrationBean configure [AbstractFilterRegistrationBean.java:259] Mapping filter: 'requestLoggingFilter' to: [/*]
2020-02-25 21:08:28,626 INFO default [localhost-startStop-1] org.springframework.boot.web.servlet.FilterRegistrationBean configure [AbstractFilterRegistrationBean.java:259] Mapping filter: 'applicationContextIdFilter' to: [/*]
2020-02-25 21:08:28,634 DEBUG default [localhost-startStop-1] org.springframework.web.filter.CommonsRequestLoggingFilter init [GenericFilterBean.java:208] Initializing filter 'requestLoggingFilter'
2020-02-25 21:08:28,634 DEBUG default [localhost-startStop-1] org.springframework.web.filter.CommonsRequestLoggingFilter init [GenericFilterBean.java:239] Filter 'requestLoggingFilter' configured successfully
2020-02-25 21:08:28,997 INFO default [main] org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter initControllerAdviceCache [RequestMappingHandlerAdapter.java:556] Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@5c33f1a9: startup date [Tue Feb 25 21:08:27 CET 2020]; root of context hierarchy
2020-02-25 21:08:29,027 INFO default [main] org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/error]}" onto public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)
2020-02-25 21:08:29,028 INFO default [main] org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/error],produces=[text/html]}" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)
2020-02-25 21:08:29,044 INFO default [main] org.springframework.web.servlet.handler.SimpleUrlHandlerMapping registerHandler [AbstractUrlHandlerMapping.java:362] Mapped URL path [/webjars/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2020-02-25 21:08:29,044 INFO default [main] org.springframework.web.servlet.handler.SimpleUrlHandlerMapping registerHandler [AbstractUrlHandlerMapping.java:362] Mapped URL path [/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2020-02-25 21:08:29,062 INFO default [main] org.springframework.web.servlet.handler.SimpleUrlHandlerMapping registerHandler [AbstractUrlHandlerMapping.java:362] Mapped URL path [/**/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]
2020-02-25 21:08:29,206 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/info || /info.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2020-02-25 21:08:29,207 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/metrics/{name:.*}],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.MetricsMvcEndpoint.value(java.lang.String)
2020-02-25 21:08:29,207 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/metrics || /metrics.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2020-02-25 21:08:29,208 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/loggers/{name:.*}],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.LoggersMvcEndpoint.get(java.lang.String)
2020-02-25 21:08:29,208 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/loggers/{name:.*}],methods=[POST],consumes=[application/vnd.spring-boot.actuator.v1+json || application/json],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.LoggersMvcEndpoint.set(java.lang.String,java.util.Map<java.lang.String, java.lang.String>)
2020-02-25 21:08:29,208 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/loggers || /loggers.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2020-02-25 21:08:29,209 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/auditevents || /auditevents.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public org.springframework.http.ResponseEntity<?> org.springframework.boot.actuate.endpoint.mvc.AuditEventsMvcEndpoint.findByPrincipalAndAfterAndType(java.lang.String,java.util.Date,java.lang.String)
2020-02-25 21:08:29,209 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/autoconfig || /autoconfig.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2020-02-25 21:08:29,210 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/configprops || /configprops.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2020-02-25 21:08:29,210 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/trace || /trace.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2020-02-25 21:08:29,211 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/dump || /dump.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2020-02-25 21:08:29,211 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/heapdump || /heapdump.json],methods=[GET],produces=[application/octet-stream]}" onto public void org.springframework.boot.actuate.endpoint.mvc.HeapdumpMvcEndpoint.invoke(boolean,javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse) throws java.io.IOException,javax.servlet.ServletException
2020-02-25 21:08:29,211 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/beans || /beans.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2020-02-25 21:08:29,212 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/health || /health.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.HealthMvcEndpoint.invoke(javax.servlet.http.HttpServletRequest,java.security.Principal)
2020-02-25 21:08:29,212 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/mappings || /mappings.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2020-02-25 21:08:29,212 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/env/{name:.*}],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EnvironmentMvcEndpoint.value(java.lang.String)
2020-02-25 21:08:29,212 INFO default [main] org.springframework.boot.actuate.endpoint.mvc.EndpointHandlerMapping register [AbstractHandlerMethodMapping.java:544] Mapped "{[/env || /env.json],methods=[GET],produces=[application/vnd.spring-boot.actuator.v1+json || application/json]}" onto public java.lang.Object org.springframework.boot.actuate.endpoint.mvc.EndpointMvcAdapter.invoke()
2020-02-25 21:08:29,306 INFO default [main] org.springframework.jmx.export.annotation.AnnotationMBeanExporter afterSingletonsInstantiated [MBeanExporter.java:431] Registering beans for JMX exposure on startup
2020-02-25 21:08:29,309 INFO default [main] org.springframework.boot.actuate.endpoint.jmx.EndpointMBeanExporter afterSingletonsInstantiated [MBeanExporter.java:431] Registering beans for JMX exposure on startup
2020-02-25 21:08:29,311 INFO default [main] org.springframework.context.support.DefaultLifecycleProcessor start [DefaultLifecycleProcessor.java:345] Starting beans in phase 0
2020-02-25 21:08:29,312 INFO default [main] org.springframework.boot.actuate.endpoint.jmx.EndpointMBeanExporter registerBeanInstance [MBeanExporter.java:679] Located managed bean 'auditEventsEndpoint': registering with JMX server as MBean [org.springframework.boot:type=Endpoint,name=auditEventsEndpoint]
2020-02-25 21:08:29,319 INFO default [main] org.springframework.boot.actuate.endpoint.jmx.EndpointMBeanExporter registerBeanInstance [MBeanExporter.java:679] Located managed bean 'requestMappingEndpoint': registering with JMX server as MBean [org.springframework.boot:type=Endpoint,name=requestMappingEndpoint]
2020-02-25 21:08:29,324 INFO default [main] org.springframework.boot.actuate.endpoint.jmx.EndpointMBeanExporter registerBeanInstance [MBeanExporter.java:679] Located managed bean 'environmentEndpoint': registering with JMX server as MBean [org.springframework.boot:type=Endpoint,name=environmentEndpoint]
2020-02-25 21:08:29,326 INFO default [main] org.springframework.boot.actuate.endpoint.jmx.EndpointMBeanExporter registerBeanInstance [MBeanExporter.java:679] Located managed bean 'healthEndpoint': registering with JMX server as MBean [org.springframework.boot:type=Endpoint,name=healthEndpoint]
2020-02-25 21:08:29,327 INFO default [main] org.springframework.boot.actuate.endpoint.jmx.EndpointMBeanExporter registerBeanInstance [MBeanExporter.java:679] Located managed bean 'beansEndpoint': registering with JMX server as MBean [org.springframework.boot:type=Endpoint,name=beansEndpoint]
2020-02-25 21:08:29,329 INFO default [main] org.springframework.boot.actuate.endpoint.jmx.EndpointMBeanExporter registerBeanInstance [MBeanExporter.java:679] Located managed bean 'infoEndpoint': registering with JMX server as MBean [org.springframework.boot:type=Endpoint,name=infoEndpoint]
2020-02-25 21:08:29,330 INFO default [main] org.springframework.boot.actuate.endpoint.jmx.EndpointMBeanExporter registerBeanInstance [MBeanExporter.java:679] Located managed bean 'loggersEndpoint': registering with JMX server as MBean [org.springframework.boot:type=Endpoint,name=loggersEndpoint]
2020-02-25 21:08:29,333 INFO default [main] org.springframework.boot.actuate.endpoint.jmx.EndpointMBeanExporter registerBeanInstance [MBeanExporter.java:679] Located managed bean 'metricsEndpoint': registering with JMX server as MBean [org.springframework.boot:type=Endpoint,name=metricsEndpoint]
2020-02-25 21:08:29,334 INFO default [main] org.springframework.boot.actuate.endpoint.jmx.EndpointMBeanExporter registerBeanInstance [MBeanExporter.java:679] Located managed bean 'traceEndpoint': registering with JMX server as MBean [org.springframework.boot:type=Endpoint,name=traceEndpoint]
2020-02-25 21:08:29,336 INFO default [main] org.springframework.boot.actuate.endpoint.jmx.EndpointMBeanExporter registerBeanInstance [MBeanExporter.java:679] Located managed bean 'dumpEndpoint': registering with JMX server as MBean [org.springframework.boot:type=Endpoint,name=dumpEndpoint]
2020-02-25 21:08:29,337 INFO default [main] org.springframework.boot.actuate.endpoint.jmx.EndpointMBeanExporter registerBeanInstance [MBeanExporter.java:679] Located managed bean 'autoConfigurationReportEndpoint': registering with JMX server as MBean [org.springframework.boot:type=Endpoint,name=autoConfigurationReportEndpoint]
2020-02-25 21:08:29,338 INFO default [main] org.springframework.boot.actuate.endpoint.jmx.EndpointMBeanExporter registerBeanInstance [MBeanExporter.java:679] Located managed bean 'configurationPropertiesReportEndpoint': registering with JMX server as MBean [org.springframework.boot:type=Endpoint,name=configurationPropertiesReportEndpoint]
2020-02-25 21:08:29,346 INFO default [main] org.apache.coyote.http11.Http11NioProtocol log [DirectJDKLog.java:183] Starting ProtocolHandler ["http-nio-8081"]
2020-02-25 21:08:29,352 INFO default [main] org.apache.tomcat.util.net.NioSelectorPool log [DirectJDKLog.java:183] Using a shared selector for servlet write/read
2020-02-25 21:08:29,359 INFO default [main] org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainer start [TomcatEmbeddedServletContainer.java:216] Tomcat started on port(s): 8081 (http)
2020-02-25 21:08:29,362 INFO default [main] com.listgroup.piu.PiuApplication logStarted [StartupInfoLogger.java:57] Started PiuApplication in 1.836 seconds (JVM running for 2.362)
The Spring @Autowired annotations does only work with objects created by Spring.
It does not initialize attributes created by you using the new Keyword.
Instead, as this answer states, you'll have to move your code to another class.
@Component
public class CommandLineAppStartupRunner implements CommandLineRunner {
@Autowired private DirezioneRegionaleService service;
@Override public void run(String...args) throws Exception {
List<DirezioneRegionale> dirRegs = service.getAllDirRegs();
System.out.println(dirRegs);
}
}
This class will be automatically be created by Spring and will therefore know the initialized Service.
The run method will also be executed automatically after Spring initializes everything.