我是Spring的初学者，我尝试了一个简单的java-mysql持久化示例。
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.example</groupId>
<artifactId>mysqlConnect</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>mysqlConnect</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.4.3.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<!--<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>-->
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
spring.datasource.url=jdbc:mysql://localhost:3306/demo
spring.datasource.username=user
spring.datasource.password=password
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
package com.example.models;
import javax.persistence.*;
@Entity
@Table(name = "Student")
public class Student {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String name;
private String town;
protected Student() {
}
public Student(String name, String town) {
this.name = name;
this.town = town;
}
@Column(name = "id")
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
@Column(name = "name")
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@Column(name = "town")
public String getTown() {
return town;
}
public void setTown(String town) {
this.town = town;
}
@Override
public String toString() {
return "Student{" +
"town='" + town + '\'' +
", name='" + name + '\'' +
'}';
}
}
package com.example.services;
import com.example.models.Student;
import org.springframework.data.repository.CrudRepository;
import java.util.List;
public interface StudentsServices extends CrudRepository<Student, Long> {
List<Student> findByName(String name);
}
package com.example;
import com.example.models.Student;
import com.example.services.StudentsServices;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
@SpringBootApplication
public class MysqlConnectApplication {
private static final Logger log = LoggerFactory.getLogger(MysqlConnectApplication.class);
public static void main(String[] args) {
SpringApplication.run(MysqlConnectApplication.class, args);
}
@Bean
public CommandLineRunner demo(StudentsServices repository){
return args -> {
log.info("Saving Tom");
repository.save(new Student("Tom", "London"));
log.info("****************************************************");
log.info("Saving Jerry");
repository.save(new Student("Jerry", "New-york"));
log.info("****************************************************");
log.info("Reeding All");
for (Student student : repository.findAll()){log.info(student.toString());}
log.info("****************************************************");
log.info("Found by name");
for (Student student : repository.findByName("Thuwarakesh")){
log.info(student.toString());
}
log.info("****************************************************");
};
}
}
CREATE TABLE IF NOT EXISTS Student(
id INT AUTO_INCREMENT,
name VARCHAR(25),
town VARCHAR(26),
PRIMARY KEY (id)
);
当我对此进行编译并运行jar文件时，我得到了以下异常。
java.lang.IllegalStateException: Failed to execute CommandLineRunner
at org.springframework.boot.SpringApplication.callRunner(SpringApplication.java:803) [spring-boot-1.4.3.RELEASE.jar!/:1.4.3.RELEASE]
at org.springframework.boot.SpringApplication.callRunners(SpringApplication.java:784) [spring-boot-1.4.3.RELEASE.jar!/:1.4.3.RELEASE]
at org.springframework.boot.SpringApplication.afterRefresh(SpringApplication.java:771) [spring-boot-1.4.3.RELEASE.jar!/:1.4.3.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:316) [spring-boot-1.4.3.RELEASE.jar!/:1.4.3.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1186) [spring-boot-1.4.3.RELEASE.jar!/:1.4.3.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1175) [spring-boot-1.4.3.RELEASE.jar!/:1.4.3.RELEASE]
at com.example.MysqlConnectApplication.main(MysqlConnectApplication.java:18) [classes!/:0.0.1-SNAPSHOT]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_45]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_45]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_45]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_45]
at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:48) [mysqlConnect-0.0.1-SNAPSHOT.jar:0.0.1-SNAPSHOT]
at org.springframework.boot.loader.Launcher.launch(Launcher.java:87) [mysqlConnect-0.0.1-SNAPSHOT.jar:0.0.1-SNAPSHOT]
at org.springframework.boot.loader.Launcher.launch(Launcher.java:50) [mysqlConnect-0.0.1-SNAPSHOT.jar:0.0.1-SNAPSHOT]
at org.springframework.boot.loader.JarLauncher.main(JarLauncher.java:51) [mysqlConnect-0.0.1-SNAPSHOT.jar:0.0.1-SNAPSHOT]
Caused by: org.springframework.orm.jpa.JpaSystemException: The database returned no natively generated identity value; nested exception is org.hibernate.HibernateException: The database returned no natively generated identity value
at org.springframework.orm.jpa.vendor.HibernateJpaDialect.convertHibernateAccessException(HibernateJpaDialect.java:333) ~[spring-orm-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.orm.jpa.vendor.HibernateJpaDialect.translateExceptionIfPossible(HibernateJpaDialect.java:244) ~[spring-orm-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.translateExceptionIfPossible(AbstractEntityManagerFactoryBean.java:491) ~[spring-orm-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.dao.support.ChainedPersistenceExceptionTranslator.translateExceptionIfPossible(ChainedPersistenceExceptionTranslator.java:59) ~[spring-tx-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.dao.support.DataAccessUtils.translateIfNecessary(DataAccessUtils.java:213) ~[spring-tx-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:147) ~[spring-tx-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodInterceptor.invoke(CrudMethodMetadataPostProcessor.java:133) ~[spring-data-jpa-1.10.6.RELEASE.jar!/:na]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) ~[spring-aop-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:213) ~[spring-aop-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at com.sun.proxy.$Proxy59.save(Unknown Source) ~[na:na]
at com.example.MysqlConnectApplication.lambda$demo$0(MysqlConnectApplication.java:25) [classes!/:0.0.1-SNAPSHOT]
at com.example.MysqlConnectApplication$$Lambda$7/889729797.run(Unknown Source) ~[na:na]
at org.springframework.boot.SpringApplication.callRunner(SpringApplication.java:800) [spring-boot-1.4.3.RELEASE.jar!/:1.4.3.RELEASE]
... 14 common frames omitted
Caused by: org.hibernate.HibernateException: The database returned no natively generated identity value
at org.hibernate.id.IdentifierGeneratorHelper.getGeneratedIdentity(IdentifierGeneratorHelper.java:71) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.dialect.identity.GetGeneratedKeysDelegate.executeAndExtract(GetGeneratedKeysDelegate.java:61) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.id.insert.AbstractReturningDelegate.performInsert(AbstractReturningDelegate.java:42) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2803) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:3374) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.action.internal.EntityIdentityInsertAction.execute(EntityIdentityInsertAction.java:81) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.engine.spi.ActionQueue.execute(ActionQueue.java:619) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.engine.spi.ActionQueue.addResolvedEntityInsertAction(ActionQueue.java:273) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.engine.spi.ActionQueue.addInsertAction(ActionQueue.java:254) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.engine.spi.ActionQueue.addAction(ActionQueue.java:299) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.event.internal.AbstractSaveEventListener.addInsertAction(AbstractSaveEventListener.java:317) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.event.internal.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:272) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.event.internal.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:178) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.event.internal.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:109) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.jpa.event.internal.core.JpaPersistEventListener.saveWithGeneratedId(JpaPersistEventListener.java:67) ~[hibernate-entitymanager-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.event.internal.DefaultPersistEventListener.entityIsTransient(DefaultPersistEventListener.java:189) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:132) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:58) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.internal.SessionImpl.firePersist(SessionImpl.java:775) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.internal.SessionImpl.persist(SessionImpl.java:748) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.internal.SessionImpl.persist(SessionImpl.java:753) ~[hibernate-core-5.0.11.Final.jar!/:5.0.11.Final]
at org.hibernate.jpa.spi.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:1146) ~[hibernate-entitymanager-5.0.11.Final.jar!/:5.0.11.Final]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_45]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_45]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_45]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_45]
at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:298) ~[spring-orm-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at com.sun.proxy.$Proxy57.persist(Unknown Source) ~[na:na]
at org.springframework.data.jpa.repository.support.SimpleJpaRepository.save(SimpleJpaRepository.java:506) ~[spring-data-jpa-1.10.6.RELEASE.jar!/:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_45]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_45]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_45]
at java.lang.reflect.Method.invoke(Method.java:497) ~[na:1.8.0_45]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.executeMethodOn(RepositoryFactorySupport.java:503) ~[spring-data-commons-1.12.6.RELEASE.jar!/:na]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:488) ~[spring-data-commons-1.12.6.RELEASE.jar!/:na]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:460) ~[spring-data-commons-1.12.6.RELEASE.jar!/:na]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:61) ~[spring-data-commons-1.12.6.RELEASE.jar!/:na]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99) ~[spring-tx-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:282) ~[spring-tx-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96) ~[spring-tx-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:136) ~[spring-tx-4.3.5.RELEASE.jar!/:4.3.5.RELEASE]
... 24 common frames omitted