*Service 中构造函数的参数 0 需要找不到类型为“*Repository”的 bean

Question

我对 Spring 完全陌生。我已经关注了这个tutorial

目前我们在 z/OS 上使用 DB2，所以我尝试使用与教程连接到 H2 相同的方式连接到 DB2。但是经过一番努力，我成功地使用 Maven 安装了 Jar 文件。但是当我尝试运行这个 Jar 时，我得到了这个错误

---

应用程序启动失败

---

说明：

构造函数的参数٠ in ess.nbe.dev.essentis.services.Tgen008Service 需要一个 bean 类型 'ess.nbe.dev.essentis.repo.Tgen008Repository' 找不到。

行动：

考虑定义一个 bean 类型 'ess.nbe.dev.essentis.repo.Tgen008Repository' 在您的配置中。

我认为项目结构符合 Spring 要求disccussed here 。

我按照说明进行操作，但无法弄清楚问题所在？

这是我的代码

package ess.nbe.dev.essentis.domain;


import org.springframework.context.annotation.Bean;

import javax.persistence.*;
import java.io.Serializable;


@Entity
public class Tgen008 implements Serializable {

    @Id
    private String ACT_IDN_SKY;

    @Column
    private String ACT_RFE_NBR_TXT;

    public Tgen008(String ACT_IDN_SKY, String ACT_RFE_NBR_TXT) {
        this.ACT_IDN_SKY = ACT_IDN_SKY;
        this.ACT_RFE_NBR_TXT = ACT_RFE_NBR_TXT;
    }

    public Tgen008() {
    }

    public String getACT_IDN_SKY() {
        return ACT_IDN_SKY;
    }

    public void setACT_IDN_SKY(String ACT_IDN_SKY) {
        this.ACT_IDN_SKY = ACT_IDN_SKY;
    }

    public String getACT_RFE_NBR_TXT() {
        return ACT_RFE_NBR_TXT;
    }

    public void setACT_RFE_NBR_TXT(String ACT_RFE_NBR_TXT) {
        this.ACT_RFE_NBR_TXT = ACT_RFE_NBR_TXT;
    }
}

这是我的存储库：

package ess.nbe.dev.essentis.repo;

import ess.nbe.dev.essentis.domain.Tgen008;
import org.springframework.data.repository.CrudRepository;

public interface Tgen008Repository extends CrudRepository<Tgen008,String> {

}

这是我的服务：

package ess.nbe.dev.essentis.services;

import ess.nbe.dev.essentis.repo.Tgen008Repository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class Tgen008Service {
    private Tgen008Repository tgen008Repository;

    @Autowired
    public Tgen008Service(Tgen008Repository tgen008Repository) {
        this.tgen008Repository = tgen008Repository;
    }

    public long total() { return tgen008Repository.count();}
}

和我的 MainApplication ：

package ess.nbe.dev.essentis;

import ess.nbe.dev.essentis.repo.Tgen008Repository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;

import java.util.Arrays;

@SpringBootApplication
public class EssentisApplication {

    public static void main(String[] args) {

        SpringApplication.run(EssentisApplication.class, args);
    }

    @Bean
    CommandLineRunner init(Tgen008Repository tgen008Repository) {
        return args -> tgen008Repository.count();
    }
}

和 Application.properties ：

# ===============================
# = DATA SOURCE
# ===============================
# Set here configurations for the database connection
spring.datasource.url=jdbc:db2://ipAddress:port/DBName
spring.datasource.username=username
spring.datasource.password=password
spring.jpa.properties.hibernate.default_schema=Qualifier
spring.datasource.driver-class-name=com.ibm.db2.jcc.DB2Driver
# Keep the connection alive if idle for a long time (needed in production)
spring.datasource.testWhileIdle=true
spring.datasource.validationQuery=select 1 from tgen008 fetch first row only
# Naming strategy
spring.jpa.hibernate.naming.implicit-strategy=org.hibernate.boot.model.naming.ImplicitNamingStrategyLegacyHbmImpl
spring.jpa.hibernate.naming.physical-strategy=org.springframework.boot.orm.jpa.hibernate.SpringPhysicalNamingStrategy
# Allows Hibernate to generate SQL optimized for a particular DBMS
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.DB2Dialect

还有我的 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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>ess.nbe.dev</groupId>
    <artifactId>essentis</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>essentis</name>
    <description>Program for Essentis DB</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <repositories>
        <repository>
            <id>com.ibm.db2.jcc</id>
            <releases>
                <enabled>true</enabled>
                <checksumPolicy>ignore</checksumPolicy>
            </releases>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
            <url>file://${project.basedir}/lib/</url>
        </repository>
    </repositories>

    <dependencies>
<!--        <dependency>
            <groupId>com.ibm.db2.jcc</groupId>
            <artifactId>db2jcc</artifactId>
            <version>10.1</version>
        </dependency>-->

        <dependency>
            <groupId>com.ibm.db2.jcc</groupId>
            <artifactId>db2jcc_license_cisuz</artifactId>
            <version>10.1</version>
        </dependency>

        <dependency>
            <groupId>com.ibm.db2.jcc</groupId>
            <artifactId>db2java</artifactId>
            <version>10.1</version>
        </dependency>

        <dependency>
            <groupId>com.ibm.db2.jcc</groupId>
            <artifactId>db2jcc_javax</artifactId>
            <version>10.1</version>
        </dependency>

        <dependency>
            <groupId>com.ibm.db2.jcc</groupId>
            <artifactId>db2jcc4</artifactId>
            <version>10.1</version>
        </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-data-rest</artifactId>
        </dependency>

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

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

Answer 1

更改您的服务：

@Service
public class Tgen008Service {
    @Autowired
    private Tgen008Repository tgen008Repository;

    public long total() { return tgen008Repository.count();}
}

Answer 2

我发现了问题所在，我有 2 个 jar 文件 db2jcc.jar 和 db2jcc4.jar。

两者都在我的存储库中，似乎该程序使用的是 db2jcc.jar 而不是 db2jcc4.jar 尽管我没有将它添加到 pom.xml 中。

所以从本地存储库中删除 db2jcc.jar 解决了问题。

更多关于这两个 Jars 区别的细节可以在this link找到

Answer 3

package ess.nbe.dev.essentis.repo;

import ess.nbe.dev.essentis.domain.Tgen008;
import org.springframework.data.repository.CrudRepository;

@Repository // Need to add this
public interface Tgen008Repository extends CrudRepository<Tgen008, String> {

}