java - Hibernate:无法创建请求的服务

Question

我想尝试使用 JPQL，但整个程序溢出，我不知道为什么。我阅读了类似问题的一些答案，并尝试添加各种依赖项、不同的 java 版本，但没有任何帮助。当我使用 spring-boota + jpa 时，我在所有情况下都会遇到相同的错误

我的 POJO 类

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import java.io.Serializable;

@Entity
public class Product implements Serializable {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String name;
    private String producer;
    private Double price;

    public Product(){}

    public Product(String name, String producer, Double price){
        this.name = name;
        this.price = price;
        this.producer = producer;
    }

    public Long getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getProducer() {
        return producer;
    }

    public void setProducer(String producer) {
        this.producer = producer;
    }

    public Double getPrice() {
        return price;
    }

    public void setPrice(Double price) {
        this.price = price;
    }

    @Override
    public String toString() {
        return "Product{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", producer='" + producer + '\'' +
                ", price=" + price +
                '}';
    }
}

我的 dao 类

import main.model.Product;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;

import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.Query;
import javax.persistence.TypedQuery;
import java.util.List;

@Repository
@Transactional
public class ProductDao {

    private EntityManager entityManager;

    @PersistenceContext
    public void setEntityManager(EntityManager entityManager){
        this.entityManager = entityManager;
    }

    public Product get(Long id){
        return entityManager.find(Product.class, id);
    }

    public void save(Product product){
        entityManager.persist(product);
    }

    public List<Product> getAll(){
        final String getAll = "SELECT p FROM Product p";
        TypedQuery<Product> getAllQuery = entityManager.createQuery(getAll, Product.class);
        List<Product> resultList = getAllQuery.getResultList();
        return resultList;
    }

    public void deleteAll(){
        final String deleteAll = "DELETE FROM Product p";
        Query deleteAllQuery = entityManager.createQuery(deleteAll);
        deleteAllQuery.executeUpdate();
    }

    public List<Product> customGet(String jpql){
        TypedQuery<Product> query = entityManager.createQuery(jpql, Product.class);
        return query.getResultList();
    }
}

主类

import main.dao.ProductDao;
import main.model.Product;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;

import java.util.ArrayList;
import java.util.List;

@SpringBootApplication
public class SpringJpaQueiresApplication {

    public static void main(String[] args) {
        ConfigurableApplicationContext ctx = SpringApplication.run(SpringJpaQueiresApplication.class, args);

        List<Product> products = new ArrayList<>();
        products.add(new Product("Telewizor", "Samsung", 4500.0));
        products.add(new Product("Opiekacz", "Opiex", 120.0));
        products.add(new Product("Laptop", "Samsung", 3599.0));
        products.add(new Product("Kino domowe", "Yamaha", 2600.0));
        products.add(new Product("Smartfon", "Sony", 2100.0));

        ProductDao productDao = ctx.getBean(ProductDao.class);
        products.forEach(productDao::save);

        System.out.println("All products");
        List<Product> allProducts = productDao.getAll();
        allProducts.forEach(System.out::println);

        System.out.println("Products more expensive than 3000");
        List<Product> expensiveProduct = productDao.customGet("SELECT p FROM Product p WHERE p.price > 3000");
        expensiveProduct.forEach(System.out::println);

        System.out.println("All products ordered by price");
        List<Product> orderedList = productDao.customGet("SELECT p FROM Product p ORDER BY p.price ASC");
        orderedList.forEach(System.out::println);

        System.out.println("Expensive Samsung product");
        List<Product> samsungList =
                productDao.customGet("SELECT p FROM Product p WHERE p.product = 'Samsung' AND p.price > 4000");
        samsungList.forEach(System.out::println);

        productDao.deleteAll();

        ctx.close();
    }
}

和属性文件

spring.datasource.url=jdbc:mysql://localhost:3306/library?useSSL=false
spring.datasource.username=root
spring.datasource.password=admin
spring.jpa.hibernate.ddl-auto=create

我的pom文件

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.8.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>main</groupId>
    <artifactId>spring-jpa-queires</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>spring-jpa-queires</name>
    <description>Demo project for Spring Boot</description>

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

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

</project>

我收到此错误

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 org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1778) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:593) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1105) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:867) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:742) [spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:389) [spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:311) [spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1213) [spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1202) [spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
    at main.SpringJpaQueiresApplication.main(SpringJpaQueiresApplication.java:16) [classes/:na]
Caused by: org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:275) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:237) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:214) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.id.factory.internal.DefaultIdentifierGeneratorFactory.injectServices(DefaultIdentifierGeneratorFactory.java:152) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.injectDependencies(AbstractServiceRegistryImpl.java:286) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:243) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:214) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.<init>(InFlightMetadataCollectorImpl.java:179) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:119) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.metadata(EntityManagerFactoryBuilderImpl.java:904) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:935) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:57) ~[spring-orm-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:365) ~[spring-orm-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:390) ~[spring-orm-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:377) ~[spring-orm-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.afterPropertiesSet(LocalContainerEntityManagerFactoryBean.java:341) ~[spring-orm-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1837) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1774) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
    ... 15 common frames omitted
Caused by: org.hibernate.HibernateException: Access to DialectResolutionInfo cannot be null when 'hibernate.dialect' not set
    at org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl.determineDialect(DialectFactoryImpl.java:100) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl.buildDialect(DialectFactoryImpl.java:54) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:137) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:35) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.initiateService(StandardServiceRegistryImpl.java:94) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:263) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
    ... 32 common frames omitted

Answer 1

堆栈跟踪已经告诉你，hibernate.dialect 没有设置。您需要添加到属性文件中:

spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect