创建名称为“greetingController”的 bean 时出错：通过字段“occupationClusterRepository”表示的依赖关系不满足答案

【问题标题】：Error creating bean with name 'greetingController': Unsatisfied dependency expressed through field 'occupationClusterRepository'创建名称为“greetingController”的 bean 时出错：通过字段“occupationClusterRepository”表示的依赖关系不满足
【发布时间】：2020-12-12 04:17:01
【问题描述】：

pom.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>2.3.3.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.jobtech</groupId>
    <artifactId>occupation-selector</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>occupation-selector</name>
    <description>Implementing the occupation selector workflow into talented.</description>

    <properties>
        <java.version>11</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.17</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

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

</project>

Application.java

package com.jobtech;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class Application {

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

}

JpaConfiguration.java

package com.jobtech;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.orm.jpa.JpaVendorAdapter;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.Database;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;

import javax.sql.DataSource;

@Configuration
@EnableJpaRepositories("com.jobtech.repository")
public class JpaConfiguration {
    @Bean
    public DataSource dataSource() {
        DriverManagerDataSource dataSource = new DriverManagerDataSource();
        dataSource.setDriverClassName("com.mysql.jdbc.Driver");
        dataSource.setUrl("jdbc:mysql://localhost:3306/jobtech");
        dataSource.setUsername("root");

        return dataSource;
    }

    @Bean
    public JpaVendorAdapter jpaVendorAdapter() {
        HibernateJpaVendorAdapter jpaVendorAdapter = new HibernateJpaVendorAdapter();
        jpaVendorAdapter.setDatabase(Database.MYSQL);
        jpaVendorAdapter.setGenerateDdl(true);

        return jpaVendorAdapter;
    }

    @Bean
    public LocalContainerEntityManagerFactoryBean entityManagerFactory() {
        LocalContainerEntityManagerFactoryBean lemfb = new LocalContainerEntityManagerFactoryBean();
        lemfb.setDataSource(dataSource());
        lemfb.setJpaVendorAdapter(jpaVendorAdapter());
        lemfb.setPackagesToScan("com.jobtech.occupation.selector.model");

        return lemfb;
    }
}

OccupationCluster.java

package com.jobtech.model;

import javax.persistence.Entity;
import javax.persistence.Table;
import javax.persistence.Id;
import javax.persistence.Column;
import javax.persistence.OneToMany;
import java.util.Set;

@Entity
@Table(name = "occupation_clusters")
public class OccupationCluster {
    @Id
    @Column(name = "cluster_id")
    private Long clusterId;

    @Column(name = "cluster_display_name")
    private String clusterDisplayName;

    @Column(name = "cluster_display_name_two")
    private String clusterDisplayNameTwo;

    @Column(name = "cluster_display_name_three")
    private String clusterDisplayNameThree;

    @OneToMany
    private Set<ClusterSkill> skills;

    public Long getClusterId() {
        return clusterId;
    }

    public void setClusterId(Long id) {
        clusterId = id;
    }

    public String getClusterDisplayName() {
        return clusterDisplayName;
    }

    public void setClusterDisplayName(String displayName) {
        clusterDisplayName = displayName;
    }

    public String getClusterDisplayNameTwo() {
        return clusterDisplayNameTwo;
    }

    public void setClusterDisplayNameTwo(String displayName) {
        clusterDisplayNameTwo = displayName;
    }

    public String getClusterDisplayNameThree() {
        return clusterDisplayNameThree;
    }

    public void setClusterDisplayNameThree(String displayName) {
        clusterDisplayNameThree = displayName;
    }

    public Set<ClusterSkill> getSkills() { return skills; }

    public void setSkills(Set<ClusterSkill> clusterSkills) { skills = clusterSkills; }
}

OccupationClusterRepository.java

package com.jobtech.repository;

import com.jobtech.model.OccupationCluster;
import org.springframework.data.repository.CrudRepository;
import org.springframework.stereotype.Repository;

@Repository
public interface OccupationClusterRepository extends CrudRepository<OccupationCluster, Long> {

}

当我运行时：./mvnw spring-boot:run 我收到以下错误：

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'greetingController': Unsatisfied dependency expressed through field 'occupationClusterRepository'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'occupationClusterRepository' defined in com.jobtech.repository.OccupationClusterRepository defined in @EnableJpaRepositories declared on JpaConfiguration: Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: Not a managed type: class com.jobtech.model.OccupationCluster
        at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:643) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
        at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:130) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
        at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:399) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1420) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:593) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:516) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:324) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:226) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:322) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:897) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
        at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:879) ~[spring-context-5.2.8.RELEASE.jar:5.2.8.RELEASE]
        at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:551) ~[spring-context-5.2.8.RELEASE.jar:5.2.8.RELEASE]
        at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:143) ~[spring-boot-2.3.3.RELEASE.jar:2.3.3.RELEASE]
        at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:758) ~[spring-boot-2.3.3.RELEASE.jar:2.3.3.RELEASE]
        at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:750) ~[spring-boot-2.3.3.RELEASE.jar:2.3.3.RELEASE]
        at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) ~[spring-boot-2.3.3.RELEASE.jar:2.3.3.RELEASE]
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) ~[spring-boot-2.3.3.RELEASE.jar:2.3.3.RELEASE]
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1237) ~[spring-boot-2.3.3.RELEASE.jar:2.3.3.RELEASE]
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) ~[spring-boot-2.3.3.RELEASE.jar:2.3.3.RELEASE]
        at com.jobtech.Application.main(Application.java:10) ~[classes/:na]
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
        at java.base/java.lang.reflect.Method.invoke(Method.java:567) ~[na:na]
        at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) ~[spring-boot-devtools-2.3.3.RELEASE.jar:2.3.3.RELEASE]

我不明白为什么，因为我用 @Entity 注释了我的模型。

【问题讨论】：

nested exception is java.lang.IllegalArgumentException: Not a managed type: class com.jobtech.model.OccupationCluster 告诉你你的 OccupationCluster 类没有被 Spring 管理。你在某处有@ComponentScan 注释吗？
不，我没有，但是我刚刚google了一下，发现@SpringBootApplication注解只是三个注解的组合：@Configuration，@EnableAutoConfiguration，@ComponentScan这不应该解决我的问题吗？
看一下setPackagesToScan中的包。这与实体的包装不匹配。
理论上是的。除了@Configuration 和@EnableJpaRepositories 之外，我还使用@EnableAutoConfiguration、@EntityScan(basePackages = {"your.domain.package.here"}) 和@EnableTransactionManagement 配置我的存储库。

标签： java spring spring-boot spring-mvc spring-data-jpa

【解决方案1】：

尝试向OccupationCluster Entity 添加一个无参数构造器。如果你使用的是 Lombok，只需要添加@NoArgsConstructor 注解即可：

@AllArgsConstructor
@NoArgsConstructor
@Getter
@ToString
@EqualsAndHashCode
public class User {
    private Long userId;
    private String shortName;
}

【讨论】：