错误创建使用名称＆＃x27; EntityManagerFactory＆＃x27;在类路径Springboot中定义

Question

尝试了所有可能的解决方案，但无法解决此错误。该应用程序非常基本。当我使用MySQL版本8.0.22时，我使用了MySqldialect 8，但错误仍然存​​在。解决此问题应采取的措施。这是我遇到错误启动ApplicationContext的错误

。要显示条件报告报告，请启用“调试”重新运行您的应用程序。 2022-07-08 20：28：36.746错误7660 --- [main] osboot.springapplication：应用程序运行失败

org.springframework.beans.beans.beans.factory.beancreatory.beancreationexpection.beancreationexpection：错误创建具有'entityManagerFactory'在类中的bean创建' [org/springframework/boot/autoconfigure/orm/jpa/hibernatejpaconfiguration.class]：init方法的调用失败；嵌套异常是org.hibernate.service.spi.serviceException：无法创建请求的服务[org.hibernate.engine.jdbc.env.spi.jdbcenvironments]

pom.xm.xml.xml

<?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>2.7.1</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>

    <groupId>com.springrest</groupId>
    <artifactId>springrest</artifactId>

    <version>0.0.1-SNAPSHOT</version>

    <name>springrest</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>17</java.version>
    </properties>
    <dependencies>

        <dependency>


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


    </dependencies>

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

</project>

/strong>

server.port=8050

#database configuration:mysql

spring.datasource.url=jdbc:mysql://localhost:3306/sampledb
spring.datasource.username=root
spring.datasource.password=password
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

#Hibernate config

spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=true
spring.jpa.properties.hibernate.dialect="org.hibernate.dialect,MySQL8Dialect"
spring.jpa.properties.hibernate.temp.use_jdbc_metadata_defaults=false

course.java

@Entity

public class Course {

    @Id

    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "<seq name in java in generator anno>")

    @SequenceGenerator(name = "<seq name in java in generator anno>", sequenceName = "<seq name in db>", allocationSize = 1)

    private int id;
    private String title;
    private String desc;

    public int getId() {
        return id;
    }

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

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getDesc() {
        return desc;
    }

    public void setDesc(String desc) {
        this.desc = desc;
    }

    public Course() {
        super();
    }

    public Course(int id, String title, String desc) {
        super();
        this.id = id;
        this.title = title;
        this.desc = desc;
    }

}

Answer 1

我认为您制作了错别字并用过“”，而不是“”。

尝试将“ org.hibernate.dialect，mysql8dialect”更改为“配置文件中的org.hibernate.dialect.mysql8dialect”。

检查数据库URL是否正确，以及数据库是否启动并运行。还要检查您的用户名和密码是否正确。