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我尝试用静态方法为类编写单元测试。
当我使用 @RunWith(MockitoJUnitRunner.class)
时,我的测试运行成功,但是当我将其更改为 @RunWith(SpringRunner.class)
时,出现此错误:
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_172]
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_172]
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_172]
at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_172]
at com.mysql.jdbc.Util.handleNewInstance(Util.java:404) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:988) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:341) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2251) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2284) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2083) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:806) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_172]
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_172]
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_172]
at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_172]
at com.mysql.jdbc.Util.handleNewInstance(Util.java:404) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:410) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:328) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:319) ~[tomcat-jdbc-9.0.10.jar:na]
at org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:212) ~[tomcat-jdbc-9.0.10.jar:na]
at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:739) [tomcat-jdbc-9.0.10.jar:na]
at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:671) [tomcat-jdbc-9.0.10.jar:na]
at org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:483) [tomcat-jdbc-9.0.10.jar:na]
at org.apache.tomcat.jdbc.pool.ConnectionPool.<init>(ConnectionPool.java:154) [tomcat-jdbc-9.0.10.jar:na]
at org.apache.tomcat.jdbc.pool.DataSourceProxy.pCreatePool(DataSourceProxy.java:118) [tomcat-jdbc-9.0.10.jar:na]
at org.apache.tomcat.jdbc.pool.DataSourceProxy.createPool(DataSourceProxy.java:107) [tomcat-jdbc-9.0.10.jar:na]
at org.apache.tomcat.jdbc.pool.DataSourceProxy.getConnection(DataSourceProxy.java:131) [tomcat-jdbc-9.0.10.jar:na]
at org.hibernate.engine.jdbc.connections.internal.DatasourceConnectionProviderImpl.getConnection(DatasourceConnectionProviderImpl.java:122) [hibernate-core-5.0.9.Final.jar:5.0.9.Final]
at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator$ConnectionProviderJdbcConnectionAccess.obtainConnection(JdbcEnvironmentInitiator.java:180) [hibernate-core-5.0.9.Final.jar:5.0.9.Final]
at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:68) [hibernate-core-5.0.9.Final.jar:5.0.9.Final]
at org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService(JdbcEnvironmentInitiator.java:35) [hibernate-core-5.0.9.Final.jar:5.0.9.Final]
at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.initiateService(StandardServiceRegistryImpl.java:88) [hibernate-core-5.0.9.Final.jar:5.0.9.Final]
at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:234) [hibernate-core-5.0.9.Final.jar:5.0.9.Final]
at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:208) [hibernate-core-5.0.9.Final.jar:5.0.9.Final]
at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:189) [hibernate-core-5.0.9.Final.jar:5.0.9.Final]
at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:51) [hibernate-core-5.0.9.Final.jar:5.0.9.Final]
at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94) [hibernate-core-5.0.9.Final.jar:5.0.9.Final]
at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:217) [hibernate-core-5.0.9.Final.jar:5.0.9.Final]
at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:189) [hibernate-core-5.0.9.Final.jar:5.0.9.Final]
at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.handleTypes(MetadataBuildingProcess.java:352) [hibernate-core-5.0.9.Final.jar:5.0.9.Final]
at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:111) [hibernate-core-5.0.9.Final.jar:5.0.9.Final]
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.metadata(EntityManagerFactoryBuilderImpl.java:847) [hibernate-entitymanager-5.0.9.Final.jar:5.0.9.Final]
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:874) [hibernate-entitymanager-5.0.9.Final.jar:5.0.9.Final]
at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:60) [spring-orm-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:338) [spring-orm-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:373) [spring-orm-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:362) [spring-orm-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1637) [spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1574) [spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:545) [spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) [spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) [spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) [spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) [spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) [spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1076) [spring-context-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:851) [spring-context-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:541) [spring-context-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759) [spring-boot-1.4.0.RELEASE.jar:1.4.0.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:369) [spring-boot-1.4.0.RELEASE.jar:1.4.0.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:313) [spring-boot-1.4.0.RELEASE.jar:1.4.0.RELEASE]
at org.springframework.boot.test.context.SpringBootContextLoader.loadContext(SpringBootContextLoader.java:111) [spring-boot-test-1.4.0.RELEASE.jar:1.4.0.RELEASE]
at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:98) [spring-test-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:116) [spring-test-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.test.context.support.DefaultTestContext.getApplicationContext(DefaultTestContext.java:83) [spring-test-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.test.context.web.ServletTestExecutionListener.setUpRequestContextIfNecessary(ServletTestExecutionListener.java:189) [spring-test-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.test.context.web.ServletTestExecutionListener.prepareTestInstance(ServletTestExecutionListener.java:131) [spring-test-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:230) [spring-test-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:228) [spring-test-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:287) [spring-test-4.3.2.RELEASE.jar:4.3.2.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:289) [spring-test-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:247) [spring-test-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:94) [spring-test-4.3.2.RELEASE.jar:4.3.2.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$2.evaluate(ParentRunner.java:268) [junit-4.12.jar:4.12]
at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61) [spring-test-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70) [spring-test-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.junit.runners.ParentRunner.run(ParentRunner.java:363) [junit-4.12.jar:4.12]
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:191) [spring-test-4.3.2.RELEASE.jar:4.3.2.RELEASE]
at org.junit.runner.JUnitCore.run(JUnitCore.java:137) [junit-4.12.jar:4.12]
at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68) [junit-rt.jar:na]
at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47) [junit-rt.jar:na]
at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242) [junit-rt.jar:na]
at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70) [junit-rt.jar:na]
Caused by: java.net.ConnectException: Connection refused: connect
at java.net.DualStackPlainSocketImpl.connect0(Native Method) ~[na:1.8.0_172]
at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:79) ~[na:1.8.0_172]
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350) ~[na:1.8.0_172]
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206) ~[na:1.8.0_172]
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188) ~[na:1.8.0_172]
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172) ~[na:1.8.0_172]
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) ~[na:1.8.0_172]
at java.net.Socket.connect(Socket.java:589) ~[na:1.8.0_172]
at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:211) ~[mysql-connector-java-5.1.39.jar:5.1.39]
at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:300) ~[mysql-connector-java-5.1.39.jar:5.1.39]
... 82 common frames omitted
测试类是:
@RunWith(SpringRunner.class)
@SpringBootTest
public class DateUtilTest {
Date date1, date2;
{
try {
date1 = new SimpleDateFormat("dd/MM/yyyy").parse("17/02/2018");
date2 = new SimpleDateFormat("dd/MM/yyyy HH:mm:ss").parse("17/02/2018 10:05:11");
} catch (ParseException e) {
e.printStackTrace();
}
}
@Test
public void testTimestampFormat_WithJustDate() {
String result = Deencapsulation.invoke(DateUtil.class, "timestampFormat", date1);
assertEquals("2018-02-17 00:00:00", result);
}
@Test
public void testTimestampFormat_WithFullDate() {
String result = Deencapsulation.invoke(DateUtil.class, "timestampFormat", date2);
assertEquals("2018-02-17 10:05:11", result);
}
}
我的 pom.xml :
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.4.0.RELEASE</version>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
<exclusions>
<exclusion>
<groupId>com.zaxxer</groupId>
<artifactId>HikariCP</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
</dependency>
<dependency>
<groupId>org.powermock</groupId>
<artifactId>powermock-module-junit4</artifactId>
<version>1.7.3</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.powermock</groupId>
<artifactId>powermock-api-mockito</artifactId>
<version>1.7.3</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>tomcat-jdbc</artifactId>
<version>9.0.10</version>
</dependency>
<dependency>
<groupId>org.jmockit</groupId>
<artifactId>jmockit</artifactId>
<version>1.24</version>
<scope>test</scope>
</dependency>
</dependencies>
不需要数据库连接的测试。那么为什么会出现数据库错误呢?
我的同事使用这种方式,但他的测试运行! (在同一个项目中)
最佳答案
简而言之,当你放置
@RunWith(SpringRunner.class)
@SpringBootTest
在测试类上,它试图“模仿”整个spring boot微服务启动过程。除其他外,尝试配置数据库驱动程序。所以它失败了,因为当您运行测试时,数据库可能不可用。所以它是一种运行集成测试
的方法另一方面,
@RunWith(MockitoJUnitRunner.class)
用于运行单元测试。它只允许使用 mockito 进行一些方便的模拟定义,它根本不加载 spring。
因此,我的回答是:首先,请确保您了解这两种测试之间的区别,因为它们完全不同。这对于编写好的测试至关重要。
您在问题中显示的 DateUtilTest
类,IMO 应该包含单元测试,因此请使用 MockitoJUnitRunner
并且不要尝试加载 spring。
关于java - 使用 SpringRunner 进行单元测试并得到 jdbc 错误,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/56920276/
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