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找不到包(多模块spring项目)

maven spring java

Leonardo Leandro · 技术社区 · 6 年前

Spring Initializr 要创建两个模块:

(这是SpringWeb)

分贝 (这是Spring数据MongoDB)

mvn clean install 带有构建成功消息。没问题。

但是,如果我尝试创建一个测试(或者甚至在 主要的 结构),其中它使用 mvn清洁安装

结构是:

api
\- src/main/java
  \- com.example.api.controllers
    \- UserController.java
\- src/test/java
  \- com.example.api.controllers
    \- UserControllerTest.java
db
\- src/main/java
  \- com.example.db.repositories
    \- UserRepository.java
model
\- src/main/java
  \- com.example.model
    \- User.java

ApiApplication.java

package com.example.api;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.server.WebServerFactoryCustomizer;
import org.springframework.boot.web.servlet.server.ConfigurableServletWebServerFactory;
import org.springframework.web.servlet.config.annotation.CorsRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@SpringBootApplication
public class ApiApplication {

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

}

UserController.java

package com.example.api.controllers;

import com.example.api.Constants;
import com.example.db.repositories.UserRepository;
import com.example.model.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class UserController {
    @Autowired
    private UserRepository userRepository;

    @GetMapping(Constants.V1 + "user")
    public User getUser() {
        User user = new User("John");
        userRepository.save(user);
        return user;
    }
}

现在,如果我跑 mvn清洁安装 ,我将收到maven的错误声明 package com.example.db.repositories does not exist

分贝是模块中的依赖项 应用程序编程接口 应用程序编程接口 模块设置为在在家长的pom中。

父-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>com.example</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>pom</packaging>

    <modules>
        <module>model</module>
        <module>db</module>
        <module>api</module>
    </modules>

</project>

<?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>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.1.RELEASE</version>
        <relativePath/>
    </parent>

    <groupId>com.example</groupId>
    <artifactId>db</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-mongodb</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.example</groupId>
            <artifactId>model</artifactId>
            <version>0.0.1-SNAPSHOT</version>
            <scope>compile</scope>
        </dependency>
    </dependencies>

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

</project>

api-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>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>LATEST</version>
        <relativePath/>
    </parent>

    <groupId>com.example</groupId>
    <artifactId>api</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>com.example</groupId>
            <artifactId>db</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

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

</project>

如何让maven看到这个包?

使其找到包后出现新错误

2019-01-14 19:16:55.060  WARN 31104 --- [           main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userController': Unsatisfied dependency expressed through field 'userRepository'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.example.db.repositories.UserRepository' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
2019-01-14 19:16:55.066  INFO 31104 --- [           main] o.apache.catalina.core.StandardService   : Stopping service [Tomcat]
2019-01-14 19:16:55.087  INFO 31104 --- [           main] ConditionEvaluationReportLoggingListener : 

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2019-01-14 19:16:55.224 ERROR 31104 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 

***************************
APPLICATION FAILED TO START
***************************

Description:

Field userRepository in com.example.api.controllers.UserController required a bean of type 'com.example.db.repositories.UserRepository' that could not be found.

The injection point has the following annotations:
        - @org.springframework.beans.factory.annotation.Autowired(required=true)


Action:

Consider defining a bean of type 'com.example.db.repositories.UserRepository' in your configuration.

3 回复 | 直到 6 年前

priyank-sriv 6 年前

你正在(重新)包装 db 作为Spring引导的“应用程序”,而不是使用 spring-boot-maven-plugin

<plugin>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-maven-plugin</artifactId>
  <executions>
    <execution>
      <goals>
        <goal>repackage</goal>
      </goals>
    </execution>
  </executions>
</plugin>

,从而加入 com.example.db.repositories 包(及其类)在BOOT-INF文件夹中。这会导致编译失败。

<plugin>..</plugin> 离别 db/pom.xml api 单元

注:我假设有 Main

thst 6 年前

Springboot自动发现将仅从您的配置类下降。你的申请在

com.example.api

com.example.db

也可以将搜索路径添加到autodiscover.db,或者将应用程序类移动到com.example,或者将db代码移动到com.example.api

@ComponentScan(âcom.exampleâ)
@SpringBootApplication
public class ExampleApplication  {

选择2

@ComponentScan({"com.example.api","com.example.db"})
@SpringBootApplication
public class ExampleApplication {

您还可以将scanBasePackages属性添加到SpringbootApplication注释中,以获得相同的效果。

@SpringBootApplication(scanBasePackages= {"com.example.api","com.example.db"})
public class ExampleApplication {

https://docs.spring.io/spring-boot/docs/current/api/org/springframework/boot/autoconfigure/SpringBootApplication.html#scanBasePackages--

Grim 6 年前

实际上,API必须看到DB类。

确保:

父项目为打包类型 pom ( <packaging>pom</packaging>
附属国 与数据库的版本相同