Java SpringBootJUnit测试通过构造函数注入注入dao接口

好的，所以我尝试设置一个springboot/junit测试，测试通过构造函数注入注入到其他类的DAO。 最初我尝试了构造函数注入

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest;
import org.springframework.test.context.junit4.SpringRunner;
import com.portfolio.bork.webapp.services.db.ProjectDao;

@RunWith(SpringRunner.class)
@DataJpaTest
@AutoConfigureTestDatabase(replace = AutoConfigureTestDatabase.Replace.NONE)
public class ProjectDaoTest  {

    ProjectDao projectDao;

    @Test
    public void getProject() {
        assert projectDao.getProjectById(1L) != null;
    }

    public ProjectDaoTest() {}

    public ProjectDaoTest(ProjectDao projectDao) {
        this.projectDao = projectDao;
    }

    public void setProjectDao(ProjectDao projectDao) {
        this.projectDao = projectDao;
    }
}

但随后会收到错误消息

java.lang.IllegalArgumentException: Test class can only have one constructor

然后环顾四周，看到了一些选项，这些选项可以归结为使用JUnit5（允许多个构造函数）或使用Mockito来实现。 我更愿意坚持spring starter测试包中的内容。所以我选择了mockito路线。因此

import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.junit.MockitoJUnitRunner;
import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest;
// import org.springframework.test.context.junit4.SpringRunner;
import com.portfolio.bork.webapp.services.db.ProjectDao;

@RunWith(MockitoJUnitRunner.class)
@DataJpaTest
@AutoConfigureTestDatabase(replace = AutoConfigureTestDatabase.Replace.NONE)

public class ProjectDaoTest  {

    @InjectMocks ProjectDao projectDao;

    @Test
    public void getProject() {
        assert projectDao.getProjectById(1L) != null;

    }

    public ProjectDaoTest() {}

    public void setProjectDao(ProjectDao projectDao) {
        this.projectDao = projectDao;
    }
}

但是遇到这个问题,

org.mockito.exceptions.base.MockitoException: 

Cannot instantiate @InjectMocks field named 'projectDao'! Cause: the type 'ProjectDao' is an interface.
You haven't provided the instance at field declaration so I tried to construct the instance.
Examples of correct usage of @InjectMocks:
@InjectMocks Service service = new Service();
@InjectMocks Service service;
//and... don't forget about some @Mocks for injection :)

如果我试图模拟DAO实现（我正试图避免），我会得到一个错误

@InjectMocks ProjectDaoImpl projectDao;

// error
java.lang.NullPointerException at com.portfolio.bork.webapp.daotest.ProjectDaoTest.getProject(ProjectDaoTest.java:23)

这是我的DAO接口

public interface ProjectDao {
    public Project getProjectById(Long projectId);
}

其实施

package com.portfolio.bork.webapp.services.db;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import com.portfolio.bork.webapp.model.Project;

@Repository
public class ProjectDaoImpl implements ProjectDao {

    @PersistenceContext
    private EntityManager entityManager;

    @Autowired
    public ProjectDaoImpl() {}

    public Project getProjectById(Long projectId) {
        return entityManager.find(Project.class, projectId);
    }
}

我在我的Rest控制器中使用它们

@RestController
public class ProjectRestController {

    private ProjectDao projectDao;

    ...

    // for constructor injection
    public ProjectRestController(ProjectDao projectDao) {
        this.projectDao = projectDao;
    }

    public void setProjectDao(ProjectDao projectDao) {
        this.projectDao = projectDao;
    }

}

这是我的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 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>2.2.5.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.portfolio.bork</groupId>
    <artifactId>webapp</artifactId>
    <version>01</version>
    <packaging>war</packaging>
    <name>webapp</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>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>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>


        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <!-- <scope>runtime</scope> -->
        </dependency>


    </dependencies>

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

</project>

如中所述

您可以使用@DataJpaTest注释来测试JPA应用程序。默认情况下，它扫描@Entity类并配置Spring数据JPA存储库。如果类路径上有一个嵌入式数据库，那么它也会配置一个。常规@Component bean未加载到ApplicationContext中

您的存储库不是Spring数据存储库，因此不会加载到上下文中

在您的案例中，IMHO使用Spring数据repo（如果需要，可以使用自定义方法）是一种可行的方法

---

另请参见：

尝试仅使用

@Mock

而不是

@injectmock

我尝试过，但没有解决编译问题：Mock无法解析为com.portfolio.bork.webapp.daotest.ProjectDaoTest的类型。（ProjectDaoTest.java:19）错误是什么？你进口了吗？

package com.portfolio.bork.webapp;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.junit.MockitoJUnitRunner;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.jdbc.AutoConfigureTestDatabase;
import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest;
import org.springframework.test.context.junit4.SpringRunner;

// import org.springframework.test.context.junit4.SpringRunner;
import com.portfolio.bork.webapp.services.db.ProjectDao;
import com.portfolio.bork.webapp.services.db.ProjectDaoImpl;

@RunWith(SpringRunner.class)
@DataJpaTest
@AutoConfigureTestDatabase(replace = AutoConfigureTestDatabase.Replace.NONE)

public class ProjectDaoTest  {

    ProjectDao projectDao;

    @Test
    public void getProject() {
        assert projectDao.getProjectById(1L) != null;

    }

    public ProjectDaoTest() {}

    @Autowired
    public void setProjectDao(ProjectDao projectDao) {
        this.projectDao = projectDao;
    }
}



2020-04-20 19:16:12.256 ERROR 21124 --- [           main] o.s.test.context.TestContextManager      : Caught exception while allowing TestExecutionListener [org.springframework.boot.test.autoconfigure.SpringBootDependencyInjectionTestExecutionListener@68567e20] to prepare test instance [com.portfolio.bork.webapp.ProjectDaoTest@593aaf41]

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'com.portfolio.bork.webapp.ProjectDaoTest': Unsatisfied dependency expressed through 
method 'setProjectDao' parameter 0; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.portfolio.bork.webapp.services.db.ProjectDao' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
        at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredMethodElement.inject(AutowiredAnnotationBeanPostProcessor.java:723) ~[spring-beans-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:130) ~[spring-beans-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:399) ~[spring-beans-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1422) ~[spring-beans-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireBeanProperties(AbstractAutowireCapableBeanFactory.java:393) ~[spring-beans-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:119) ~[spring-test-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:83) ~[spring-test-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.springframework.boot.test.autoconfigure.SpringBootDependencyInjectionTestExecutionListener.prepareTestInstance(SpringBootDependencyInjectionTestExecutionListener.java:43) ~[spring-boot-test-autoconfigure-2.2.5.RELEASE.jar:2.2.5.RELEASE]
        at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:244) ~[spring-test-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:227) [spring-test-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:289) [spring-test-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) [junit-4.12.jar:4.12]
        at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:291) [spring-test-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:246) [spring-test-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:97) [spring-test-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290) [junit-4.12.jar:4.12]
        at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71) [junit-4.12.jar:4.12]
        at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288) [junit-4.12.jar:4.12]
        at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58) [junit-4.12.jar:4.12]
        at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268) [junit-4.12.jar:4.12]
        at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61) [spring-test-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70) [spring-test-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.junit.runners.ParentRunner.run(ParentRunner.java:363) [junit-4.12.jar:4.12]
        at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190) [spring-test-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.junit.runner.JUnitCore.run(JUnitCore.java:137) [junit-4.12.jar:4.12]
        at org.junit.runner.JUnitCore.run(JUnitCore.java:115) [junit-4.12.jar:4.12]
        at org.junit.vintage.engine.execution.RunnerExecutor.execute(RunnerExecutor.java:40) [junit-vintage-engine-5.5.2.jar:5.5.2]
        at java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:184) ~[na:1.8.0_161]
        at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193) ~[na:1.8.0_161]
        at java.util.Iterator.forEachRemaining(Iterator.java:116) ~[na:1.8.0_161]
        at java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1801) ~[na:1.8.0_161]
        at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481) ~[na:1.8.0_161]
        at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471) ~[na:1.8.0_161]
        at java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:151) ~[na:1.8.0_161]
        at java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:174) ~[na:1.8.0_161]
        at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[na:1.8.0_161]
        at java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:418) ~[na:1.8.0_161]
        at org.junit.vintage.engine.VintageTestEngine.executeAllChildren(VintageTestEngine.java:80) ~[junit-vintage-engine-5.5.2.jar:5.5.2]
        at org.junit.vintage.engine.VintageTestEngine.execute(VintageTestEngine.java:71) ~[junit-vintage-engine-5.5.2.jar:5.5.2]
        at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:220) ~[junit-platform-launcher-1.3.1.jar:1.3.1]
        at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$6(DefaultLauncher.java:188) ~[junit-platform-launcher-1.3.1.jar:1.3.1]
        at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:202) ~[junit-platform-launcher-1.3.1.jar:1.3.1]
        at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:181) ~[junit-platform-launcher-1.3.1.jar:1.3.1]
        at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:128) ~[junit-platform-launcher-1.3.1.jar:1.3.1]
        at org.apache.maven.surefire.junitplatform.JUnitPlatformProvider.invokeAllTests(JUnitPlatformProvider.java:150) ~[surefire-junit-platform-2.22.2.jar:2.22.2]
        at org.apache.maven.surefire.junitplatform.JUnitPlatformProvider.invoke(JUnitPlatformProvider.java:124) ~[surefire-junit-platform-2.22.2.jar:2.22.2]
        at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:384) ~[surefire-booter-2.22.2.jar:2.22.2]
        at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:345) ~[surefire-booter-2.22.2.jar:2.22.2]
        at org.apache.maven.surefire.booter.ForkedBooter.execute(ForkedBooter.java:126) ~[surefire-booter-2.22.2.jar:2.22.2]
        at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:418) ~[surefire-booter-2.22.2.jar:2.22.2]
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.portfolio.bork.webapp.services.db.ProjectDao' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1695) ~[spring-beans-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1253) ~[spring-beans-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1207) ~[spring-beans-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredMethodElement.inject(AutowiredAnnotationBeanPostProcessor.java:715) ~[spring-beans-5.2.4.RELEASE.jar:5.2.4.RELEASE]
        ... 49 common frames omitted