SpringBoot之Failed to load ApplicationContext

1.遇到的问题

报以下错误

java.lang.IllegalStateException: Failed to load ApplicationContext

注:后面附带完整的控制台报错

找到到问题:在配置yml时,少写了一个空格。如下图所示

加上即可解决如下问题。

Failed to bind properties under 'logging.level' to java.util.Map<java.lang.String, org.springframework.boot.logging.LogLevel>

 但这问题解决了,新的问题又来了

org.springframework.jdbc.BadSqlGrammarException: 
### Error querying database.  Cause: org.h2.jdbc.JdbcSQLSyntaxErrorException: Table "USER" not found; SQL statement:

Caused by: org.springframework.jdbc.datasource.init.ScriptStatementFailedException: Failed to execute SQL script statement #1 of class path resource [db/data-h2.sql]: DELETE FROM user; nested exception is org.h2.jdbc.JdbcSQLSyntaxErrorException: Table "USER" not found; SQL statement:
DELETE FROM user [42102-200]

找到原因是:h2数据库中的表名是user3,与实体类中的User的名称不一致造成的。如下图所示:

2、解决办法

1、h2数据库中表名与实体类名称保持一致即可解决。

2、在User类上加@TableName 注解,对实体类自定的名称和数据库表名保持一致即可。

 总结一下,遇到问题首先看控制台报错,根据报错解决相应问题,比如是否写注解、配置文件是否写漏了空格,特别是在yml配置文件中。

 在这过程我也查询了其他的解决方案,可以参考。 

方法1、解决：Failed to load ApplicationContext

方法2、java.lang.IllegalStateException: Failed to load ApplicationContext 解决办法 

方法3、Failed to load ApplicationContext 的解决办法 

附件

完整报错如下

java.lang.IllegalStateException: Failed to load ApplicationContext

	at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:132)
	at org.springframework.test.context.support.DefaultTestContext.getApplicationContext(DefaultTestContext.java:123)
	at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:118)
	at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:83)
	at org.springframework.boot.test.autoconfigure.SpringBootDependencyInjectionTestExecutionListener.prepareTestInstance(SpringBootDependencyInjectionTestExecutionListener.java:43)
	at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:244)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:227)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:289)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:291)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:246)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:97)
	at org.junit.runners.ParentRunner$4.run(ParentRunner.java:331)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:79)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:329)
	at org.junit.runners.ParentRunner.access$100(ParentRunner.java:66)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:293)
	at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
	at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
	at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:413)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190)
	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
	at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:33)
	at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:230)
	at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:58)
Caused by: org.springframework.boot.context.properties.bind.BindException: Failed to bind properties under 'logging.level' to java.util.Map<java.lang.String, org.springframework.boot.logging.LogLevel>
	at org.springframework.boot.context.properties.bind.Binder.handleBindError(Binder.java:363)
	at org.springframework.boot.context.properties.bind.Binder.bind(Binder.java:323)
	at org.springframework.boot.context.properties.bind.Binder.bind(Binder.java:308)
	at org.springframework.boot.context.properties.bind.Binder.bind(Binder.java:238)
	at org.springframework.boot.context.properties.bind.Binder.bind(Binder.java:212)
	at org.springframework.boot.context.logging.LoggingApplicationListener.setLogLevels(LoggingApplicationListener.java:364)
	at org.springframework.boot.context.logging.LoggingApplicationListener.initializeFinalLoggingLevels(LoggingApplicationListener.java:331)
	at org.springframework.boot.context.logging.LoggingApplicationListener.initialize(LoggingApplicationListener.java:282)
	at org.springframework.boot.context.logging.LoggingApplicationListener.onApplicationEnvironmentPreparedEvent(LoggingApplicationListener.java:239)
	at org.springframework.boot.context.logging.LoggingApplicationListener.onApplicationEvent(LoggingApplicationListener.java:216)
	at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172)
	at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165)
	at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139)
	at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:127)
	at org.springframework.boot.context.event.EventPublishingRunListener.environmentPrepared(EventPublishingRunListener.java:80)
	at org.springframework.boot.SpringApplicationRunListeners.environmentPrepared(SpringApplicationRunListeners.java:53)
	at org.springframework.boot.SpringApplication.prepareEnvironment(SpringApplication.java:345)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:308)
	at org.springframework.boot.test.context.SpringBootContextLoader.loadContext(SpringBootContextLoader.java:120)
	at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:99)
	at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:124)
	... 26 more
Caused by: org.springframework.core.convert.ConverterNotFoundException: No converter found capable of converting from type [java.lang.String] to type [java.util.Map<java.lang.String, org.springframework.boot.logging.LogLevel>]
	at org.springframework.core.convert.support.GenericConversionService.handleConverterNotFound(GenericConversionService.java:321)
	at org.springframework.core.convert.support.GenericConversionService.convert(GenericConversionService.java:194)
	at org.springframework.boot.context.properties.bind.BindConverter$CompositeConversionService.convert(BindConverter.java:170)
	at org.springframework.boot.context.properties.bind.BindConverter.convert(BindConverter.java:96)
	at org.springframework.boot.context.properties.bind.BindConverter.convert(BindConverter.java:88)
	at org.springframework.boot.context.properties.bind.MapBinder.bindAggregate(MapBinder.java:64)
	at org.springframework.boot.context.properties.bind.AggregateBinder.bind(AggregateBinder.java:56)
	at org.springframework.boot.context.properties.bind.Binder.lambda$bindAggregate$3(Binder.java:414)
	at org.springframework.boot.context.properties.bind.Binder$Context.withIncreasedDepth(Binder.java:571)
	at org.springframework.boot.context.properties.bind.Binder$Context.access$100(Binder.java:512)
	at org.springframework.boot.context.properties.bind.Binder.bindAggregate(Binder.java:414)
	at org.springframework.boot.context.properties.bind.Binder.bindObject(Binder.java:375)
	at org.springframework.boot.context.properties.bind.Binder.bind(Binder.java:319)
	... 45 more