java - "Accesing data with MySQL"教程之后的异常 - SpringBoot JPA Hibernate

Question

我是 SpringBoot 的新手，我正在尝试通过 JPA(Hibernate) 对 mysql 进行 CRUD 访问

我关注了 https://spring.io/guides/gs/accessing-data-mysql/

当我用 Maven 编译它时，它成功地完成了，但是当我尝试从生成的 .jar 执行它时，它显示以下错误:

-(已编辑)现在提供以下堆栈跟踪:

TestSpringBoot\target>java -jar gs-mysql-data-0.1.0.jar

.   ____          _            __ _ _
/\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/  ___)| |_)| | | | | || (_| |  ) ) ) )
'  |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot ::        (v2.0.3.RELEASE)

2018-06-29 03:15:10 ERROR o.s.boot.SpringApplication - Application run failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaConfiguration.class]: Invocation of init method failed; nested exception is java.lang.NoClassDefFoundError: javax/xml/bind/JAXBException
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1708)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:581)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:503)
        at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:317)
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315)
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
        at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1089)
        at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:859)
        at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550)
        at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140)
        at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759)
        at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:395)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:327)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1255)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1243)
        at hello.Application.main(Application.java:10)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
        at java.base/java.lang.reflect.Method.invoke(Unknown Source)
        at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:48)
        at org.springframework.boot.loader.Launcher.launch(Launcher.java:87)
        at org.springframework.boot.loader.Launcher.launch(Launcher.java:50)
        at org.springframework.boot.loader.JarLauncher.main(JarLauncher.java:51)
Caused by: java.lang.NoClassDefFoundError: javax/xml/bind/JAXBException
        at org.hibernate.boot.spi.XmlMappingBinderAccess.<init>(XmlMappingBinderAccess.java:43)
        at org.hibernate.boot.MetadataSources.<init>(MetadataSources.java:86)
        at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.<init>(EntityManagerFactoryBuilderImpl.java:212)
        at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.<init>(EntityManagerFactoryBuilderImpl.java:167)
        at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:51)
        at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:365)
        at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:390)
        at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:377)
        at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.afterPropertiesSet(LocalContainerEntityManagerFactoryBean.java:341)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1767)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1704)
        ... 24 common frames omitted
Caused by: java.lang.ClassNotFoundException: javax.xml.bind.JAXBException
        at java.base/java.net.URLClassLoader.findClass(Unknown Source)
        at java.base/java.lang.ClassLoader.loadClass(Unknown Source)
        at org.springframework.boot.loader.LaunchedURLClassLoader.loadClass(LaunchedURLClassLoader.java:93)
        at java.base/java.lang.ClassLoader.loadClass(Unknown Source)
        ... 35 common frames omitted

-POM:

<?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>org.springframework</groupId>
    <artifactId>gs-mysql-data</artifactId>
    <version>0.1.0</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.3.RELEASE</version>
    </parent>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <!-- JPA Data (We are going to use Repositories, Entities, Hibernate, etc...) -->

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>

        <!-- Use MySQL Connector-J -->

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>5.3.1.Final</version>
        </dependency>
    </dependencies>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

-代码:

@SpringBootApplication
public class Application {
public static void main(String[] args) {
    SpringApplication.run(Application.class, args);
}
}

@Controller    
@RequestMapping(path="/demo") 
Application path)
public class MainController {
@Autowired 
private UserRepository userRepository;
@GetMapping(path="/add")
public @ResponseBody String addNewUser (@RequestParam String name
        , @RequestParam String email) {

    User2 n = new User2();
    n.setName(name);
    n.setEmail(email);
    userRepository.save(n);
    return "Saved";
}
@GetMapping(path="/all")
public @ResponseBody Iterable<User2> getAllUsers() {
    // This returns a JSON or XML with the users
    return userRepository.findAll();
}
}

@Entity 
public class User2 {
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
private Integer id;

private String name;

private String email;

//getters and setters...

}


public interface UserRepository extends CrudRepository <User2, Long> {
}

Maven 控制台:

[INFO] Scanning for projects...
[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building gs-mysql-data 0.1.0
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] --- maven-resources-plugin:3.0.1:resources (default-resources) @ gs-mysql-data ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 1 resource
[INFO] Copying 1 resource
[INFO] 
[INFO] --- maven-compiler-plugin:3.7.0:compile (default-compile) @ gs-mysql-data ---
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 4 source files to MyPath\TestSpringBoot\target\classes
[INFO] 
[INFO] --- maven-resources-plugin:3.0.1:testResources (default-testResources) @ gs-mysql-data ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 0 resource
[INFO] 
[INFO] --- maven-compiler-plugin:3.7.0:testCompile (default-testCompile) @ gs-mysql-data ---
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 1 source file to MyPath\TestSpringBoot\target\test-classes
[INFO] 
[INFO] --- maven-surefire-plugin:2.21.0:test (default-test) @ gs-mysql-data ---
[INFO] 
[INFO] -------------------------------------------------------
[INFO]  T E S T S
[INFO] -------------------------------------------------------
[INFO] 
[INFO] Results:
[INFO] 
[INFO] Tests run: 0, Failures: 0, Errors: 0, Skipped: 0
[INFO] 
[INFO] 
[INFO] --- maven-jar-plugin:3.0.2:jar (default-jar) @ gs-mysql-data ---
[INFO] Building jar: MyPath\TestSpringBoot\target\gs-mysql-data-0.1.0.jar
[INFO] 
[INFO] --- spring-boot-maven-plugin:2.0.3.RELEASE:repackage (default) @ gs-mysql-data ---
[INFO] 
[INFO] --- maven-install-plugin:2.5.2:install (default-install) @ gs-mysql-data ---
[INFO] Installing MyPath\TestSpringBoot\target\gs-mysql-data-0.1.0.jar to MYPath\.m2\repository\org\springframework\gs-mysql-data\0.1.0\gs-mysql-data-0.1.0.jar
[INFO] Installing MyPath\TestSpringBoot\pom.xml to MyPath\.m2\repository\org\springframework\gs-mysql-data\0.1.0\gs-mysql-data-0.1.0.pom
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2.911 s
[INFO] Finished at: 2018-06-29T02:01:08+02:00
[INFO] Final Memory: 37M/325M
[INFO] ------------------------------------------------------------------------

已解决:

正确的POM:

<?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>org.springframework</groupId>
    <artifactId>gs-mysql-data</artifactId>
    <version>0.1.0</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.3.RELEASE</version>
    </parent>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
<!--PART ADDED TO SOLVE THE PROBLEM -->
        <!-- JPA Data (We are going to use Repositories, Entities, Hibernate, etc...) -->
        <!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-core -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>5.2.3.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-entitymanager</artifactId>
            <version>5.2.3.Final</version>
        </dependency>

        <dependency>
            <groupId>javax.xml.bind</groupId>
            <artifactId>jaxb-api</artifactId>
            <version>2.3.0</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>

        <!-- Use MySQL Connector-J -->

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

Answer 1

异常很明显，您的依赖项 pom.xml 缺少一些库 Hibernate-core,...

Caused by: java.lang.ClassNotFoundException: org.hibernate.boot.model.naming.PhysicalNamingStrategy

• 请重新检查pom.xml

  <!-- JPA Data (We are going to use Repositories, Entities, Hibernate, etc...) -->
  
   <!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-core -->
   <dependency>
      <groupId>org.hibernate</groupId>
      <artifactId>hibernate-core</artifactId>
      <version>5.3.1.Final</version>
   </dependency>
  
    <!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-entitymanager -->
    <dependency>
       <groupId>org.hibernate</groupId>
       <artifactId>hibernate-entitymanager</artifactId>
      <version>5.3.1.Final</version>
   </dependency>
  
  <!-- https://mvnrepository.com/artifact/javax.xml.bind/jaxb-api -->
  <dependency>
    <groupId>javax.xml.bind</groupId>
    <artifactId>jaxb-api</artifactId>
    <version>2.3.0</version>
  </dependency>