mybatis學習筆記三

原創 ldlly0505 2020-02-22 17:31

1.找出今天以前的user數據

mapper文件：

@Mapper
public interface UserMapper {
   
    public List<User> findByDate(Date createTime);
}

隱射文件：

<select id="findByDate" resultMap="user">
        select * from user where create_time < #{createTime}
    </select>

測試代碼：

@Test
    public void testUserByDate() {
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-mm-dd hh:MM:ss");
        //找今天以前的數據
        List<User> users = userMapper.findByDate(new Date());
        System.out.println(users.toString());
    }

結果：

2019-12-11 21:58:05.872  INFO 9748 --- [           main] o.s.s.concurrent.ThreadPoolTaskExecutor  : Shutting down ExecutorService 'applicationTaskExecutor'
2019-12-11 21:58:05.885  INFO 9748 --- [           main] ConditionEvaluationReportLoggingListener : 

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2019-12-11 21:58:05.927 ERROR 9748 --- [           main] o.s.boot.SpringApplication               : Application run failed

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [org/mybatis/spring/boot/autoconfigure/MybatisAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.ibatis.session.SqlSessionFactory]: Factory method 'sqlSessionFactory' threw exception; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [E:\Code\mybatis-demo\mybatyis-demo\demo\target\classes\mapper\UserMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error creating document instance.  Cause: org.xml.sax.SAXParseException; lineNumber: 28; columnNumber: 47; 元素內容必須由格式正確的字符數據或標記組成。
	at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:656) ~[spring-beans-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:636) ~[spring-beans-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1338) ~[spring-beans-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1177) ~[spring-beans-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:557) ~[spring-beans-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:517) ~[spring-beans-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:323) ~[spring-beans-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:321) ~[spring-beans-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~[spring-beans-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:879) ~[spring-beans-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:878) ~[spring-context-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550) ~[spring-context-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747) ~[spring-boot-2.2.2.RELEASE.jar:2.2.2.RELEASE]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) ~[spring-boot-2.2.2.RELEASE.jar:2.2.2.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) ~[spring-boot-2.2.2.RELEASE.jar:2.2.2.RELEASE]
	at org.springframework.boot.test.context.SpringBootContextLoader.loadContext(SpringBootContextLoader.java:125) [spring-boot-test-2.2.2.RELEASE.jar:2.2.2.RELEASE]
	at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:99) [spring-test-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:124) [spring-test-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.test.context.support.DefaultTestContext.getApplicationContext(DefaultTestContext.java:123) [spring-test-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.test.context.web.ServletTestExecutionListener.setUpRequestContextIfNecessary(ServletTestExecutionListener.java:190) [spring-test-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.test.context.web.ServletTestExecutionListener.prepareTestInstance(ServletTestExecutionListener.java:132) [spring-test-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:244) [spring-test-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.test.context.junit.jupiter.SpringExtension.postProcessTestInstance(SpringExtension.java:98) [spring-test-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$invokeTestInstancePostProcessors$5(ClassBasedTestDescriptor.java:337) [junit-jupiter-engine-5.5.2.jar:5.5.2]
	at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.executeAndMaskThrowable(ClassBasedTestDescriptor.java:342) [junit-jupiter-engine-5.5.2.jar:5.5.2]
	at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$invokeTestInstancePostProcessors$6(ClassBasedTestDescriptor.java:337) [junit-jupiter-engine-5.5.2.jar:5.5.2]
	at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193) ~[na:1.8.0_144]
	at java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:175) ~[na:1.8.0_144]
	at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1374) ~[na:1.8.0_144]
	at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481) ~[na:1.8.0_144]
	at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471) ~[na:1.8.0_144]
	at java.util.stream.StreamSpliterators$WrappingSpliterator.forEachRemaining(StreamSpliterators.java:312) ~[na:1.8.0_144]
	at java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:743) ~[na:1.8.0_144]
	at java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:742) ~[na:1.8.0_144]
	at java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:580) ~[na:1.8.0_144]
	at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.invokeTestInstancePostProcessors(ClassBasedTestDescriptor.java:336) [junit-jupiter-engine-5.5.2.jar:5.5.2]
	at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.instantiateAndPostProcessTestInstance(ClassBasedTestDescriptor.java:259) [junit-jupiter-engine-5.5.2.jar:5.5.2]
	at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$testInstancesProvider$2(ClassBasedTestDescriptor.java:252) [junit-jupiter-engine-5.5.2.jar:5.5.2]
	at java.util.Optional.orElseGet(Optional.java:267) ~[na:1.8.0_144]
	at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$testInstancesProvider$3(ClassBasedTestDescriptor.java:251) [junit-jupiter-engine-5.5.2.jar:5.5.2]
	at org.junit.jupiter.engine.execution.TestInstancesProvider.getTestInstances(TestInstancesProvider.java:29) ~[junit-jupiter-engine-5.5.2.jar:5.5.2]
	at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$prepare$0(TestMethodTestDescriptor.java:106) ~[junit-jupiter-engine-5.5.2.jar:5.5.2]
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.prepare(TestMethodTestDescriptor.java:105) ~[junit-jupiter-engine-5.5.2.jar:5.5.2]
	at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.prepare(TestMethodTestDescriptor.java:69) ~[junit-jupiter-engine-5.5.2.jar:5.5.2]
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$prepare$1(NodeTestTask.java:107) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.prepare(NodeTestTask.java:107) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:75) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at java.util.ArrayList.forEach(ArrayList.java:1249) ~[na:1.8.0_144]
	at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at java.util.ArrayList.forEach(ArrayList.java:1249) ~[na:1.8.0_144]
	at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51) ~[junit-platform-engine-1.5.2.jar:1.5.2]
	at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:229) ~[junit-platform-launcher-1.5.2.jar:1.5.2]
	at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$6(DefaultLauncher.java:197) ~[junit-platform-launcher-1.5.2.jar:1.5.2]
	at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:211) ~[junit-platform-launcher-1.5.2.jar:1.5.2]
	at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:191) ~[junit-platform-launcher-1.5.2.jar:1.5.2]
	at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:128) ~[junit-platform-launcher-1.5.2.jar:1.5.2]
	at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:74) ~[junit5-rt.jar:na]
	at com.intellij.rt.execution.junit.IdeaTestRunner$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: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.ibatis.session.SqlSessionFactory]: Factory method 'sqlSessionFactory' threw exception; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [E:\Code\mybatis-demo\mybatyis-demo\demo\target\classes\mapper\UserMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error creating document instance.  Cause: org.xml.sax.SAXParseException; lineNumber: 28; columnNumber: 47; 元素內容必須由格式正確的字符數據或標記組成。
	at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185) ~[spring-beans-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:651) ~[spring-beans-5.2.2.RELEASE.jar:5.2.2.RELEASE]
	... 81 common frames omitted

 

 報錯的原因是sql裏面的小於號在select標籤裏面需要用轉義符號來表示：&lt;

正確sql

 <select id="findByDate" resultMap="user">
        select * from user where create_time &lt; #{createTime}
    </select>

結果：

Wed Dec 11 22:04:20 CST 2019 WARN: Establishing SSL connection without server's identity verification is not recommended. According to MySQL 5.5.45+, 5.6.26+ and 5.7.6+ requirements SSL connection must be established by default if explicit option isn't set. For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide truststore for server certificate verification.
2019-12-11 22:04:20.560 DEBUG 5228 --- [           main] c.e.demo.mapper.UserMapper.findByDate    : ==>  Preparing: select * from user where create_time < ? 
2019-12-11 22:04:20.580 DEBUG 5228 --- [           main] c.e.demo.mapper.UserMapper.findByDate    : ==> Parameters: 2019-12-11 22:04:19.796(Timestamp)
2019-12-11 22:04:20.716 DEBUG 5228 --- [           main] c.e.demo.mapper.RoleMapper.selectById    : ====>  Preparing: select * from role where id = ? 
2019-12-11 22:04:20.717 DEBUG 5228 --- [           main] c.e.demo.mapper.RoleMapper.selectById    : ====> Parameters: 1(Long)
2019-12-11 22:04:21.054 DEBUG 5228 --- [           main] c.e.demo.mapper.RoleMapper.selectById    : <====      Total: 1
2019-12-11 22:04:21.055 DEBUG 5228 --- [           main] c.e.demo.mapper.UserMapper.findByDate    : <==      Total: 1
2019-12-11 22:04:21.057 DEBUG 5228 --- [           main] c.e.d.m.ResourceMapper.selectByRoleId    : ==>  Preparing: select * from resource where role_id = ? 
2019-12-11 22:04:21.057 DEBUG 5228 --- [           main] c.e.d.m.ResourceMapper.selectByRoleId    : ==> Parameters: 1(Long)
2019-12-11 22:04:21.094 DEBUG 5228 --- [           main] c.e.d.m.ResourceMapper.selectByRoleId    : <==      Total: 2
[User(id=1, password=111, name=aaa, roleId=1, createTime=Tue Dec 10 04:51:22 CST 2019, updateTime=Tue Dec 10 04:51:22 CST 2019, role=Role(id=1, name=老師, createTime=Tue Dec 10 04:59:03 CST 2019, updateTime=Tue Dec 10 04:59:03 CST 2019, resources=[Resource(id=1, name=查看, createTime=Tue Dec 10 04:59:26 CST 2019, updateTime=Tue Dec 10 04:59:26 CST 2019, roleId=1), Resource(id=2, name=增加, createTime=Tue Dec 10 04:59:26 CST 2019, updateTime=Tue Dec 10 04:59:26 CST 2019, roleId=1)]))]
2019-12-11 22:04:21.121  INFO 5228 --- [extShutdownHook] com.alibaba.druid.pool.DruidDataSource   : {dataSource-1} closed
2019-12-11 22:04:21.121  INFO 5228 --- [extShutdownHook] o.s.s.concurrent.ThreadPoolTaskExecutor  : Shutting down ExecutorService 'applicationTaskExecutor'

Process finished with exit code 0

 

mybatis裏的轉義符號：

&lt；	<	小於
&gt；	>	大於
&amp；	&	與
&apos；	’	單引號
&quot；	"	雙引號

或者在sql里加上：<![CDATA[ ]]>

<select id ="selectByDate" resultMap="user">
  select * from resource where create_time <![CDATA[ <=]]> #{createTime}

</select>

有興趣的可以關注公衆號：碼上行走

 

ldlly0505
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