Question

我正在研究Spring Boot 2和Hibernate 5。这次，我使用了两个表和一对多关系。错误发生在这里。

我已经在stackoverflow中找到了一些技巧，例如修改application.properties，创建名为users_sites的中间表。但是，它并不能解决我的问题。

这些是我的数据库。

CREATE TABLE `sites` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `username` varchar(45) DEFAULT NULL,
  `siteURL` varchar(255) NOT NULL,
  PRIMARY KEY (`id`),
  KEY `username_idx` (`username`),
  CONSTRAINT `username` FOREIGN KEY (`username`) REFERENCES `users` (`username`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

CREATE TABLE `users` (
  `username` varchar(45) NOT NULL,
  `password` varchar(255) NOT NULL,
  PRIMARY KEY (`username`),
  UNIQUE KEY `id_UNIQUE` (`username`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;

这些是我的模范。

Entity
@Table(name = "users")
@EntityListeners(AuditingEntityListener.class)
public class User {
    private String username;
    private String password;

    @OneToMany(mappedBy = "user", cascade = CascadeType.ALL)
    @JoinColumn(name="username")
    private List<Site> sites = new ArrayList<Site>();

    public User() {

    }

    public User(String username, String password) {
        setUsername(username);
        setPassword(password);
    }

    @Id
    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    @Column(name = "password", nullable = false)
    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public List<Site> getSites() {
        return sites;
    }

    public void setSites(List<Site> sites) {
        this.sites = sites;
    }

    public void addSite(Site site) {
        this.sites.add(site);
    }
}

@Entity
@Table(name = "sites")
@EntityListeners(AuditingEntityListener.class)
@IdClass(Site.class)
public class Site implements Serializable{
    private long id;
    private User user;
    private String siteURL;

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    @ManyToOne
    @JoinColumn(name="username", referencedColumnName = "username", insertable = false, updatable = false) 
    public User getUser() {
        return user;
    }

    public void setUser(User user) {
        this.user = user;
    }

    @Column(name = "siteURL", nullable = false)
    public String getSiteURL() {
        return siteURL;
    }

    public void setSiteURL(String siteName) {
        this.siteURL = siteName;
    }
}

错误消息在这里。

java.lang.IllegalStateException: Failed to load ApplicationContext
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:125) ~[spring-test-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.test.context.support.DefaultTestContext.getApplicationContext(DefaultTestContext.java:108) ~[spring-test-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:118) ~[spring-test-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:83) ~[spring-test-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.boot.test.autoconfigure.SpringBootDependencyInjectionTestExecutionListener.prepareTestInstance(SpringBootDependencyInjectionTestExecutionListener.java:44) ~[spring-boot-test-autoconfigure-2.1.4.RELEASE.jar:2.1.4.RELEASE]
    at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:246) ~[spring-test-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:227) ~[spring-test-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:289) ~[spring-test-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) ~[junit-4.12.jar:4.12]
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:291) ~[spring-test-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:246) ~[spring-test-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:97) ~[spring-test-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290) ~[junit-4.12.jar:4.12]
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71) ~[junit-4.12.jar:4.12]
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288) ~[junit-4.12.jar:4.12]
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58) ~[junit-4.12.jar:4.12]
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268) ~[junit-4.12.jar:4.12]
    at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61) ~[spring-test-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70) ~[spring-test-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363) ~[junit-4.12.jar:4.12]
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190) ~[spring-test-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:89) ~[.cp/:na]
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:41) ~[.cp/:na]
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:541) ~[.cp/:na]
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:763) ~[.cp/:na]
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:463) ~[.cp/:na]
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:209) ~[.cp/:na]
Caused by: 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 javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build Hibernate SessionFactory; nested exception is org.hibernate.MappingException: Could not determine type for: java.util.List, at table: users, for columns: [org.hibernate.mapping.Column(sites)]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1778) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:593) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1105) ~[spring-context-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:867) ~[spring-context-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549) ~[spring-context-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:142) ~[spring-boot-2.1.4.RELEASE.jar:2.1.4.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:775) ~[spring-boot-2.1.4.RELEASE.jar:2.1.4.RELEASE]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) ~[spring-boot-2.1.4.RELEASE.jar:2.1.4.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:316) ~[spring-boot-2.1.4.RELEASE.jar:2.1.4.RELEASE]
    at org.springframework.boot.test.context.SpringBootContextLoader.loadContext(SpringBootContextLoader.java:127) ~[spring-boot-test-2.1.4.RELEASE.jar:2.1.4.RELEASE]
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:99) ~[spring-test-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:117) ~[spring-test-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    ... 26 common frames omitted
Caused by: javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build Hibernate SessionFactory; nested exception is org.hibernate.MappingException: Could not determine type for: java.util.List, at table: users, for columns: [org.hibernate.mapping.Column(sites)]
    at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:402) ~[spring-orm-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:377) ~[spring-orm-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.afterPropertiesSet(LocalContainerEntityManagerFactoryBean.java:341) ~[spring-orm-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1837) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1774) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    ... 42 common frames omitted
Caused by: org.hibernate.MappingException: Could not determine type for: java.util.List, at table: users, for columns: [org.hibernate.mapping.Column(sites)]
    at org.hibernate.mapping.SimpleValue.getType(SimpleValue.java:486) ~[hibernate-core-5.3.9.Final.jar:5.3.9.Final]
    at org.hibernate.mapping.SimpleValue.isValid(SimpleValue.java:453) ~[hibernate-core-5.3.9.Final.jar:5.3.9.Final]
    at org.hibernate.mapping.Property.isValid(Property.java:226) ~[hibernate-core-5.3.9.Final.jar:5.3.9.Final]
    at org.hibernate.mapping.PersistentClass.validate(PersistentClass.java:624) ~[hibernate-core-5.3.9.Final.jar:5.3.9.Final]
    at org.hibernate.mapping.RootClass.validate(RootClass.java:267) ~[hibernate-core-5.3.9.Final.jar:5.3.9.Final]
    at org.hibernate.boot.internal.MetadataImpl.validate(MetadataImpl.java:347) ~[hibernate-core-5.3.9.Final.jar:5.3.9.Final]
    at org.hibernate.boot.internal.SessionFactoryBuilderImpl.build(SessionFactoryBuilderImpl.java:466) ~[hibernate-core-5.3.9.Final.jar:5.3.9.Final]
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:939) ~[hibernate-core-5.3.9.Final.jar:5.3.9.Final]
    at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:57) ~[spring-orm-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:365) ~[spring-orm-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:390) ~[spring-orm-5.1.6.RELEASE.jar:5.1.6.RELEASE]
    ... 46 common frames omitted

我该如何解决？救救我。

感谢您的回答。我通过选择答案解决了我的问题。但是，然后，我遇到了一个新问题，即没有将站点信息保存在数据库中的用户处。（可以理解，我无法从用户那里加载网站信息。）（实际上，这是一项认真的研究。）

这是我的测试代码。

@Test
    public void test() {
        Site site1 = new Site();
        site1.setSiteURL("www.test.com");
        Site site2 = new Site();
        site2.setSiteURL("www.test1.com");

        restTemplate.postForEntity(getRootUrl()+ "/sites", site1, Site.class);
        restTemplate.postForEntity(getRootUrl()+ "/sites", site2, Site.class);

        User user1 = new User();
        user1.setUsername("1111");
        user1.setPassword("12131");

        user1.addSite(site1);
        user1.addSite(site2);

        User user2 = new User();
        user2.setUsername("2222");
        user2.setPassword("1241");

        user2.addSite(site1);

        restTemplate.postForEntity(getRootUrl()+ "/users", user1, User.class);
        restTemplate.postForEntity(getRootUrl()+ "/users", user2, User.class);

        User calledUser1 = restTemplate.getForObject(getRootUrl()+"/users/"+user1.getUsername(), User.class);
        System.out.println("Username: " + calledUser1.getUsername() + ", Password: " + calledUser1.getPassword());
        for (Site site : calledUser1.getSites()) {
            System.out.println("Sign up site: " + site.getSiteURL());
        }
        User calledUser2 = restTemplate.getForObject(getRootUrl()+"/users/"+user2.getUsername(), User.class);
        System.out.println("Username: " + calledUser2.getUsername() + ", Password: " + calledUser2.getPassword());
        for (Site site : calledUser2.getSites()) {
            System.out.println("Sign up site: " + site.getSiteURL());
        }
    }

作为此代码的结果，siteURL和用户信息得到了很好的保存。但是，当我从数据库加载用户信息时，没有站点信息。你能帮我吗？

Answer 1

Caused by: org.hibernate.MappingException: Could not determine type for: java.util.List, at table: users, for columns: [org.hibernate.mapping.Column(sites)]
    at org.hibernate.mapping.SimpleValue.getType(SimpleValue.java:486) ~[hibernate-core-5.3.9.Final.jar:5.3.9.Final]
    at org.hibernate.mapping.SimpleValue.isValid(SimpleValue.java:453) ~[hibernate-core-5.3.9.Final.jar:5.3.9.Final]

关于访问策略配置。（即基于字段或基于属性的访问）。使用哪一个取决于docs中@Id的位置：

默认情况下，@ Id注释的位置为默认值访问策略。当放在字段上时，Hibernate会假设基于字段的访问。当放在标识符获取器上时，休眠将使用基于属性的访问。

在User中，将其@Id放在吸气剂上，将使用基于属性的访问，并且Hibernate将检查是否正确配置了所有吸气剂。（如果是基于字段的访问，它将改为检查字段）此处正确配置意味着吸气剂需要满足以下任何条件：

带有一些映射注释，例如@Column，@OneToMany等。
如果类型是basic type或@Entity，则即使未标记任何映射注释，也会应用默认设置。
如果不想映射，请用@Transient注释。

但是getSites()中的User不满足上述任何条件，因此会抱怨。因此，将@OneToMany从字段移至吸气剂：

private List<Site> sites = new ArrayList<Site>();

@OneToMany(mappedBy = "user", cascade = CascadeType.ALL)
public List<Site> getSites() {
        return sites;
}

如果您只想对网站使用基于字段的访问，而对其他人继续使用基于属性的访问，我相信您可以使用@Access( AccessType.FIELD )来覆盖网站字段：

@Access(AccessType.FIELD)
@OneToMany(mappedBy = "user", cascade = CascadeType.ALL)
private List<Site> sites = new ArrayList<Site>();


@Transient
public List<Site> getSites() {
        return sites;
}

Answer 2

从@JoinColumn(name="username")删除private List<Site> sites = new ArrayList<Site>();

在双向@OneToMany @ManyToOne关系中，只有一个实体可以是所有者。

检查此post以获得更多信息。

Answer 3

将applicationContext.xml文件放在src / main / resources目录中。它将被复制到classpath目录中，您应该可以使用

进行访问

@ContextConfiguration（“ / applicationContext.xml”）

从Spring-Documentation开始：纯路径（例如“ context.xml”）将被视为来自定义测试类的同一包中的类路径资源。以斜杠开头的路径被视为完全合格的类路径位置，例如“ /org/example/config.xml”。

因此在引用类路径的根目录中的文件时添加斜杠很重要

如何解决我的数据库问题？（MappingException）

3 个答案:

如何解决我的数据库问题？ （MappingException）

3 个答案:

如何解决我的数据库问题？（MappingException）