我是Spring的新人，并且遇到了以下异常
Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2019-06-12 21:48:27.204 ERROR 13289 --- [ main] o.s.boot.SpringApplication : Application run failed
java.lang.IllegalStateException: Failed to execute CommandLineRunner
at org.springframework.boot.SpringApplication.callRunner(SpringApplication.java:816) [spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE]
这是我运行应用程序的类
@SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
@Bean
CommandLineRunner init(UserRepository userRepository) {
return args -> {
Stream.of("John", "Julie", "Jennifer", "Helen", "Rachel").forEach(name -> {
User user = new User(name, name.toLowerCase() + "@domain.com");
userRepository.save(user);
});
userRepository.findAll().forEach(System.out::println);
};
}
}
这是我要遵循的指南：here
我评论了方法Stream.of中与init有关的部分，并放置了一个System.out.println("hello");，它可以正常工作。
所以问题出在Stream上。
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.1.5.RELEASE)
2019-06-12 22:48:13.015 INFO 13817 --- [ main] springboot.angularest.Application : Starting Application on Marta-Strasse.local with PID 13817 (/Users/Simone/IdeaProjects/angularest/target/classes started by Simone in /Users/Simone/IdeaProjects/angularest)
2019-06-12 22:48:13.021 INFO 13817 --- [ main] springboot.angularest.Application : No active profile set, falling back to default profiles: default
2019-06-12 22:48:15.430 INFO 13817 --- [ main] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data repositories in DEFAULT mode.
2019-06-12 22:48:15.555 INFO 13817 --- [ main] .s.d.r.c.RepositoryConfigurationDelegate : Finished Spring Data repository scanning in 114ms. Found 1 repository interfaces.
2019-06-12 22:48:16.100 INFO 13817 --- [ main] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration' of type [org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration$$EnhancerBySpringCGLIB$$d61747a1] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
2019-06-12 22:48:16.473 INFO 13817 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8080 (http)
2019-06-12 22:48:16.518 INFO 13817 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2019-06-12 22:48:16.519 INFO 13817 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/9.0.19]
2019-06-12 22:48:16.703 INFO 13817 --- [ main] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2019-06-12 22:48:16.703 INFO 13817 --- [ main] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 3524 ms
2019-06-12 22:48:16.922 INFO 13817 --- [ main] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Starting...
2019-06-12 22:48:17.057 INFO 13817 --- [ main] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Start completed.
2019-06-12 22:48:17.131 INFO 13817 --- [ main] o.hibernate.jpa.internal.util.LogHelper : HHH000204: Processing PersistenceUnitInfo [
name: default
...]
2019-06-12 22:48:17.208 INFO 13817 --- [ main] org.hibernate.Version : HHH000412: Hibernate Core {5.3.10.Final}
2019-06-12 22:48:17.220 INFO 13817 --- [ main] org.hibernate.cfg.Environment : HHH000206: hibernate.properties not found
2019-06-12 22:48:17.364 INFO 13817 --- [ main] o.hibernate.annotations.common.Version : HCANN000001: Hibernate Commons Annotations {5.0.4.Final}
2019-06-12 22:48:17.507 INFO 13817 --- [ main] org.hibernate.dialect.Dialect : HHH000400: Using dialect: org.hibernate.dialect.H2Dialect
2019-06-12 22:48:17.975 INFO 13817 --- [ main] org.hibernate.tuple.PojoInstantiator : HHH000182: No default (no-argument) constructor for class: springboot.angularest.model.User (class must be instantiated by Interceptor)
2019-06-12 22:48:18.322 INFO 13817 --- [ main] o.h.t.schema.internal.SchemaCreatorImpl : HHH000476: Executing import script 'org.hibernate.tool.schema.internal.exec.ScriptSourceInputNonExistentImpl@6451a288'
2019-06-12 22:48:18.326 INFO 13817 --- [ main] j.LocalContainerEntityManagerFactoryBean : Initialized JPA EntityManagerFactory for persistence unit 'default'
2019-06-12 22:48:18.982 INFO 13817 --- [ main] o.s.s.concurrent.ThreadPoolTaskExecutor : Initializing ExecutorService 'applicationTaskExecutor'
2019-06-12 22:48:19.030 WARN 13817 --- [ main] aWebConfiguration$JpaWebMvcConfiguration : spring.jpa.open-in-view is enabled by default. Therefore, database queries may be performed during view rendering. Explicitly configure spring.jpa.open-in-view to disable this warning
2019-06-12 22:48:19.351 INFO 13817 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8080 (http) with context path ''
2019-06-12 22:48:19.359 INFO 13817 --- [ main] springboot.angularest.Application : Started Application in 7.321 seconds (JVM running for 9.837)
2019-06-12 22:48:19.474 INFO 13817 --- [ main] o.h.h.i.QueryTranslatorFactoryInitiator : HHH000397: Using ASTQueryTranslatorFactory
2019-06-12 22:48:19.579 INFO 13817 --- [ main] ConditionEvaluationReportLoggingListener :
Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2019-06-12 22:48:19.591 ERROR 13817 --- [ main] o.s.boot.SpringApplication : Application run failed
java.lang.IllegalStateException: Failed to execute CommandLineRunner
at org.springframework.boot.SpringApplication.callRunner(SpringApplication.java:816) ~[spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.springframework.boot.SpringApplication.callRunners(SpringApplication.java:797) ~[spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:324) ~[spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1260) ~[spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1248) ~[spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE]
at springboot.angularest.Application.main(Application.java:21) ~[classes/:na]
Caused by: org.springframework.orm.jpa.JpaSystemException: No default constructor for entity: : springboot.angularest.model.User; nested exception is org.hibernate.InstantiationException: No default constructor for entity: : springboot.angularest.model.User
at org.springframework.orm.jpa.vendor.HibernateJpaDialect.convertHibernateAccessException(HibernateJpaDialect.java:351) ~[spring-orm-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.orm.jpa.vendor.HibernateJpaDialect.translateExceptionIfPossible(HibernateJpaDialect.java:253) ~[spring-orm-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.translateExceptionIfPossible(AbstractEntityManagerFactoryBean.java:527) ~[spring-orm-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.dao.support.ChainedPersistenceExceptionTranslator.translateExceptionIfPossible(ChainedPersistenceExceptionTranslator.java:61) ~[spring-tx-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.dao.support.DataAccessUtils.translateIfNecessary(DataAccessUtils.java:242) ~[spring-tx-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:153) ~[spring-tx-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodInterceptor.invoke(CrudMethodMetadataPostProcessor.java:138) ~[spring-data-jpa-2.1.8.RELEASE.jar:2.1.8.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:93) ~[spring-aop-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.data.repository.core.support.SurroundingTransactionDetectorMethodInterceptor.invoke(SurroundingTransactionDetectorMethodInterceptor.java:61) ~[spring-data-commons-2.1.8.RELEASE.jar:2.1.8.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:212) ~[spring-aop-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at com.sun.proxy.$Proxy83.findAll(Unknown Source) ~[na:na]
at springboot.angularest.Application.lambda$init$1(Application.java:33) ~[classes/:na]
at org.springframework.boot.SpringApplication.callRunner(SpringApplication.java:813) ~[spring-boot-2.1.5.RELEASE.jar:2.1.5.RELEASE]
... 5 common frames omitted
Caused by: org.hibernate.InstantiationException: No default constructor for entity: : springboot.angularest.model.User
at org.hibernate.tuple.PojoInstantiator.instantiate(PojoInstantiator.java:85) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.tuple.PojoInstantiator.instantiate(PojoInstantiator.java:105) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.tuple.entity.AbstractEntityTuplizer.instantiate(AbstractEntityTuplizer.java:673) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.persister.entity.AbstractEntityPersister.instantiate(AbstractEntityPersister.java:4950) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.internal.SessionImpl.instantiate(SessionImpl.java:1682) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.internal.SessionImpl.instantiate(SessionImpl.java:1666) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.loader.Loader.instanceNotYetLoaded(Loader.java:1663) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.loader.Loader.getRow(Loader.java:1561) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.loader.Loader.getRowFromResultSet(Loader.java:731) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.loader.Loader.processResultSet(Loader.java:990) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.loader.Loader.doQuery(Loader.java:948) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:340) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.loader.Loader.doList(Loader.java:2689) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.loader.Loader.doList(Loader.java:2672) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2506) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.loader.Loader.list(Loader.java:2501) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:504) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:395) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:220) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1508) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.query.internal.AbstractProducedQuery.doList(AbstractProducedQuery.java:1537) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.query.internal.AbstractProducedQuery.list(AbstractProducedQuery.java:1505) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.query.Query.getResultList(Query.java:132) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.query.criteria.internal.compile.CriteriaQueryTypeQueryAdapter.getResultList(CriteriaQueryTypeQueryAdapter.java:74) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.springframework.data.jpa.repository.support.SimpleJpaRepository.findAll(SimpleJpaRepository.java:313) ~[spring-data-jpa-2.1.8.RELEASE.jar:2.1.8.RELEASE]
at org.springframework.data.jpa.repository.support.SimpleJpaRepository.findAll(SimpleJpaRepository.java:74) ~[spring-data-jpa-2.1.8.RELEASE.jar:2.1.8.RELEASE]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
at java.base/java.lang.reflect.Method.invoke(Method.java:567) ~[na:na]
at org.springframework.data.repository.core.support.RepositoryComposition$RepositoryFragments.invoke(RepositoryComposition.java:359) ~[spring-data-commons-2.1.8.RELEASE.jar:2.1.8.RELEASE]
at org.springframework.data.repository.core.support.RepositoryComposition.invoke(RepositoryComposition.java:200) ~[spring-data-commons-2.1.8.RELEASE.jar:2.1.8.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$ImplementationMethodExecutionInterceptor.invoke(RepositoryFactorySupport.java:644) ~[spring-data-commons-2.1.8.RELEASE.jar:2.1.8.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:608) ~[spring-data-commons-2.1.8.RELEASE.jar:2.1.8.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.lambda$invoke$3(RepositoryFactorySupport.java:595) ~[spring-data-commons-2.1.8.RELEASE.jar:2.1.8.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:595) ~[spring-data-commons-2.1.8.RELEASE.jar:2.1.8.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:59) ~[spring-data-commons-2.1.8.RELEASE.jar:2.1.8.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:295) ~[spring-tx-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:98) ~[spring-tx-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.7.RELEASE.jar:5.1.7.RELEASE]
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:139) ~[spring-tx-5.1.7.RELEASE.jar:5.1.7.RELEASE]
... 16 common frames omitted
2019-06-12 22:48:19.598 INFO 13817 --- [ main] o.s.s.concurrent.ThreadPoolTaskExecutor : Shutting down ExecutorService 'applicationTaskExecutor'
2019-06-12 22:48:19.599 INFO 13817 --- [ main] j.LocalContainerEntityManagerFactoryBean : Closing JPA EntityManagerFactory for persistence unit 'default'
2019-06-12 22:48:19.600 INFO 13817 --- [ main] .SchemaDropperImpl$DelayedDropActionImpl : HHH000477: Starting delayed evictData of schema as part of SessionFactory shut-down'
2019-06-12 22:48:19.612 INFO 13817 --- [ main] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Shutdown initiated...
2019-06-12 22:48:19.621 INFO 13817 --- [ main] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Shutdown completed.
Process finished with exit code 1
通过在Stream.of（）上调试，我得到了：
private void callRunner(CommandLineRunner runner, ApplicationArguments args) {
try {
runner.run(args.getSourceArgs());
} catch (Exception var4) {
throw new IllegalStateException("Failed to execute CommandLineRunner", var4);
}
}
答案 0 :(得分：1)
如果提供了整个堆栈跟踪信息，并且会引起IllegalStateException的错误，则将大有帮助。此外，您可以在调试模式下运行该应用程序以获取更多信息。
我只能猜测问题出在用户实体上。
您User看起来像文档中那样吗？
@Entity
public class User {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private long id;
private final String name;
private final String email;
public User(String name, String email) {
this.name = name;
this.email = email;
}
public void setId(long id) {
this.id = id;
}
public long getId() {
return id;
}
public String getName() {
return name;
}
public String getEmail() {
return email;
}
}
编辑：
这是罪魁祸首Caused by: org.springframework.orm.jpa.JpaSystemException: No default constructor for entity: : springboot.angularest.model.User; nested exception is org.hibernate.InstantiationException: No default constructor for entity: : springboot.angularest.model.User
请尝试使用默认构造函数的User类。创建JPA实体时，必须考虑将在其上执行的反射。因此，有时甚至需要创建getter，setter和构造函数，即使您从未调用它们也是如此。：
@Entity
public class User {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
public long id;
public String name;
public String email;
public User() {}
public User(String name, String email) {
this.name = name;
this.email = email;
}
}