异常：Caused by: java.lang.NoClassDefFoundError: Could not initialize class net.sf.log4jdbc.Properties

参考文章：

使用Log4jdbc-log4j2监听MyBatis中运行的SQL和Connection

使用 log4jdbc格式化输出SQL，maven配置如下：

<dependency>
<groupId>org.bgee.log4jdbc-log4j2</groupId>
<artifactId>log4jdbc-log4j2-jdbc4</artifactId>
<version>1.16</version>
</dependency>

datasouce.xml配置如下：

    <!-- DataSource -->
    <bean id="dataSourceSpied" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> 
        <property name="driverClassName" value="${db.driver}"></property> 
        <property name="url" value="${db.url}"></property> 
        <property name="username" value="${db.username}"></property> 
        <property name="password" value="${db.password}"></property> 
    </bean>
    <!-- log4jdbc -->
    <bean id="dataSource" class="net.sf.log4jdbc.sql.jdbcapi.DataSourceSpy">
        <constructor-arg ref="dataSourceSpied" />
    </bean>

异常信息：

java.lang.IllegalStateException: Failed to load ApplicationContext
    at org.springframework.test.context.CacheAwareContextLoaderDelegate.loadContext(CacheAwareContextLoaderDelegate.java:99) ~[spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.test.context.TestContext.getApplicationContext(TestContext.java:122) ~[spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:109) ~[spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:75) ~[spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:312) ~[spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:211) [spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:288) [spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) [junit-4.11.jar:na]
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:284) [spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:231) [spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:88) [spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238) [junit-4.11.jar:na]
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63) [junit-4.11.jar:na]
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236) [junit-4.11.jar:na]
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53) [junit-4.11.jar:na]
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229) [junit-4.11.jar:na]
    at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61) [spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:71) [spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.junit.runners.ParentRunner.run(ParentRunner.java:309) [junit-4.11.jar:na]
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:174) [spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50) [.cp/:na]
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) [.cp/:na]
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459) [.cp/:na]
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:675) [.cp/:na]
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382) [.cp/:na]
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192) [.cp/:na]
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userDao' defined in file [C:stsworkspacegit	qc	qc-common-dal	argetclassesspringapplicationContext-dal.xml]: Initialization of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in URL [file:/C:/stsworkspace/git/tqc/tqc-common-dal/target/classes/spring/datasource.xml]: Cannot resolve reference to bean 'dataSource' while setting bean property 'dataSource'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in URL [file:/C:/stsworkspace/git/tqc/tqc-common-dal/target/classes/spring/datasource.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [net.sf.log4jdbc.sql.jdbcapi.DataSourceSpy]: Constructor threw exception; nested exception is java.lang.NoClassDefFoundError: Could not initialize class net.sf.log4jdbc.Properties
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:529) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:626) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:932) ~[spring-context-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:479) ~[spring-context-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:120) ~[spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:60) ~[spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.test.context.support.AbstractDelegatingSmartContextLoader.delegateLoading(AbstractDelegatingSmartContextLoader.java:100) ~[spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.test.context.support.AbstractDelegatingSmartContextLoader.loadContext(AbstractDelegatingSmartContextLoader.java:248) ~[spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.test.context.CacheAwareContextLoaderDelegate.loadContextInternal(CacheAwareContextLoaderDelegate.java:64) ~[spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.test.context.CacheAwareContextLoaderDelegate.loadContext(CacheAwareContextLoaderDelegate.java:91) ~[spring-test-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    ... 25 common frames omitted
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in URL [file:/C:/stsworkspace/git/tqc/tqc-common-dal/target/classes/spring/datasource.xml]: Cannot resolve reference to bean 'dataSource' while setting bean property 'dataSource'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in URL [file:/C:/stsworkspace/git/tqc/tqc-common-dal/target/classes/spring/datasource.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [net.sf.log4jdbc.sql.jdbcapi.DataSourceSpy]: Constructor threw exception; nested exception is java.lang.NoClassDefFoundError: Could not initialize class net.sf.log4jdbc.Properties
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:329) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:107) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1387) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1128) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireByName(AbstractAutowireCapableBeanFactory.java:1146) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1096) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    ... 39 common frames omitted
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in URL [file:/C:/stsworkspace/git/tqc/tqc-common-dal/target/classes/spring/datasource.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [net.sf.log4jdbc.sql.jdbcapi.DataSourceSpy]: Constructor threw exception; nested exception is java.lang.NoClassDefFoundError: Could not initialize class net.sf.log4jdbc.Properties
    at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:288) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1045) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:949) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:487) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:323) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    ... 51 common frames omitted
Caused by: org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [net.sf.log4jdbc.sql.jdbcapi.DataSourceSpy]: Constructor threw exception; nested exception is java.lang.NoClassDefFoundError: Could not initialize class net.sf.log4jdbc.Properties
    at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:163) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:121) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:280) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    ... 60 common frames omitted
Caused by: java.lang.NoClassDefFoundError: Could not initialize class net.sf.log4jdbc.Properties
    at net.sf.log4jdbc.log.SpyLogFactory.getSpyLogDelegator(SpyLogFactory.java:69) ~[log4jdbc-log4j2-jdbc4-1.16.jar:na]
    at net.sf.log4jdbc.sql.jdbcapi.DataSourceSpy.<init>(DataSourceSpy.java:90) ~[log4jdbc-log4j2-jdbc4-1.16.jar:na]
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_11]
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_11]
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_11]
    at java.lang.reflect.Constructor.newInstance(Constructor.java:408) ~[na:1.8.0_11]
    at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:148) ~[spring-beans-3.2.3.RELEASE.jar:3.2.3.RELEASE]
    ... 62 common frames omitted
16:44:15.402 [main] DEBUG o.s.t.c.s.DirtiesContextTestExecutionListener - After test class: context [[TestContext@8a9f61 testClass = TestUserDao, testInstance = [null], testMethod = [null], testException = [null], mergedContextConfiguration = [MergedContextConfiguration@16905e testClass = TestUserDao, locations = '{classpath*:/spring/applicationContext*.xml, classpath*:/spring/datasource.xml}', classes = '{}', contextInitializerClasses = '[]', activeProfiles = '{}', contextLoader = 'org.springframework.test.context.support.DelegatingSmartContextLoader', parent = [null]]]], dirtiesContext [false].

产生原因：

我的日志环境使用的是slf4j，log4jdbc-log4j2默认只支持log4j2，如果想要支持slf4j，则需要增加如下配置：

Configure log4jdbc-log4j2 options

log4jdbc-log4j2 can be configured in the exact same way than log4jdbc (see below). Please note two changes as compared to log4jdbc:

log4jdbc.spylogdelegator.name: this is a new option, allowing to provide the qualified class name of the logger to use. Notably, if you want to use the SLF4J logger rather than Log4j 2, you must set this option to the valuenet.sf.log4jdbc.log.slf4j.Slf4jSpyLogDelegator.

解决方案：

在classpath的jdbc.properties中增加如下配置：

#jdbc settings
#db.driver=com.mysql.jdbc.Driver
#db.url=jdbc:mysql://127.0.0.1:3306/tqc
db.driver=net.sf.log4jdbc.sql.jdbcapi.DriverSpy
db.url=jdbc:log4jdbc:mysql://127.0.0.1:3306/tqc
db.username=aaa
db.password=aaa

log4jdbc.log4j2.properties中增加如下配置

dbc.spylogdelegator.name=net.sf.log4jdbc.log.slf4j.Slf4jSpyLogDelegator
log4jdbc.debug.stack.prefix=
log4jdbc.sqltiming.warn.threshold=
log4jdbc.sqltiming.error.threshold=
log4jdbc.dump.booleanastruefalse=
log4jdbc.dump.sql.maxlinelength=
log4jdbc.dump.fulldebugstacktrace=
log4jdbc.statement.warn=
log4jdbc.dump.sql.select=
log4jdbc.dump.sql.insert=
log4jdbc.dump.sql.update=
log4jdbc.dump.sql.delete=
log4jdbc.dump.sql.create=
log4jdbc.dump.sql.addsemicolon=
log4jdbc.auto.load.popular.drivers=
log4jdbc.trim.sql=
log4jdbc.trim.sql.extrablanklines=
log4jdbc.suppress.generated.keys.exception=
log4jdbc.drivers=