Stringboot druid框架搭建的时候报错 代码及报错如下，请大佬解答感激不尽

Question

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2018-10-30 17:23:56.726 ERROR 4728 --- [ main] o.s.boot.SpringApplication : Application run failed

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'druidDataSource' defined in class path resource [com/feifan/config/DruidConfig.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.sql.DataSource]: Factory method 'druidDataSource' threw exception; nested exception is java.lang.NoClassDefFoundError: org/apache/log4j/Logger
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:591) ~[spring-beans-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1246) ~[spring-beans-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1096) ~[spring-beans-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:535) ~[spring-beans-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:495) ~[spring-beans-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:317) ~[spring-beans-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315) ~[spring-beans-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:759) ~[spring-beans-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:867) ~[spring-context-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:548) ~[spring-context-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140) ~[spring-boot-2.0.6.RELEASE.jar:2.0.6.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:754) [spring-boot-2.0.6.RELEASE.jar:2.0.6.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:386) [spring-boot-2.0.6.RELEASE.jar:2.0.6.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:307) [spring-boot-2.0.6.RELEASE.jar:2.0.6.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1242) [spring-boot-2.0.6.RELEASE.jar:2.0.6.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1230) [spring-boot-2.0.6.RELEASE.jar:2.0.6.RELEASE]
at com.feifan.WechatActivityApplication.main(WechatActivityApplication.java:18) [classes/:na]
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [javax.sql.DataSource]: Factory method 'druidDataSource' threw exception; nested exception is java.lang.NoClassDefFoundError: org/apache/log4j/Logger
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185) ~[spring-beans-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:583) ~[spring-beans-5.0.10.RELEASE.jar:5.0.10.RELEASE]
... 18 common frames omitted
Caused by: java.lang.NoClassDefFoundError: org/apache/log4j/Logger
at com.alibaba.druid.filter.logging.Log4jFilter.(Log4jFilter.java:26) ~[druid-1.1.9.jar:1.1.9]
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_121]
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_121]
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_121]
at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_121]
at java.lang.Class.newInstance(Class.java:442) ~[na:1.8.0_121]
at com.alibaba.druid.filter.FilterManager.loadFilter(FilterManager.java:114) ~[druid-1.1.9.jar:1.1.9]
at com.alibaba.druid.pool.DruidAbstractDataSource.addFilters(DruidAbstractDataSource.java:1286) ~[druid-1.1.9.jar:1.1.9]
at com.alibaba.druid.pool.DruidAbstractDataSource.setFilters(DruidAbstractDataSource.java:1275) ~[druid-1.1.9.jar:1.1.9]
at com.feifan.config.DruidConfig.druidDataSource(DruidConfig.java:44) ~[classes/:na]
at com.feifan.config.DruidConfig$$EnhancerBySpringCGLIB$$1be46309.CGLIB$druidDataSource$2() ~[classes/:na]
at com.feifan.config.DruidConfig$$EnhancerBySpringCGLIB$$1be46309$$FastClassBySpringCGLIB$$f7c1e78f.invoke() ~[classes/:na]
at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228) ~[spring-core-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:365) ~[spring-context-5.0.10.RELEASE.jar:5.0.10.RELEASE]
at com.feifan.config.DruidConfig$$EnhancerBySpringCGLIB$$1be46309.druidDataSource() ~[classes/:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_121]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_121]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_121]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_121]
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154) ~[spring-beans-5.0.10.RELEASE.jar:5.0.10.RELEASE]
... 19 common frames omitted
Caused by: java.lang.ClassNotFoundException: org.apache.log4j.Logger
at java.net.URLClassLoader.findClass(URLClassLoader.java:381) ~[na:1.8.0_121]
at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[na:1.8.0_121]
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331) ~[na:1.8.0_121]
at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[na:1.8.0_121]
... 39 common frames omitted

Disconnected from the target VM, address: '127.0.0.1:57637', transport: 'socket'

Process finished with exit code 1

Answer 1

import com.alibaba.druid.pool.DruidDataSource;
import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.sql.DataSource;
import java.sql.SQLException;

@Configuration
@EnableConfigurationProperties({DruidDataSourceProperties.class})
public class DruidConfig {
@Autowired
private DruidDataSourceProperties properties;

@Bean
@ConditionalOnMissingBean
public DataSource druidDataSource() {
    DruidDataSource druidDataSource = new DruidDataSource();
    druidDataSource.setDriverClassName(properties.getDriverClassName());
    druidDataSource.setUrl(properties.getUrl());
    druidDataSource.setUsername(properties.getUsername());
    druidDataSource.setPassword(properties.getPassword());
    druidDataSource.setInitialSize(properties.getInitialSize());
    druidDataSource.setMinIdle(properties.getMinIdle());
    druidDataSource.setMaxActive(properties.getMaxActive());
    druidDataSource.setMaxWait(properties.getMaxWait());
    druidDataSource.setTimeBetweenEvictionRunsMillis(properties.getTimeBetweenEvictionRunsMillis());
    druidDataSource.setMinEvictableIdleTimeMillis(properties.getMinEvictableIdleTimeMillis());
    druidDataSource.setValidationQuery(properties.getValidationQuery());
    druidDataSource.setTestWhileIdle(properties.isTestWhileIdle());
    druidDataSource.setTestOnBorrow(properties.isTestOnBorrow());
    druidDataSource.setTestOnReturn(properties.isTestOnReturn());
    druidDataSource.setPoolPreparedStatements(properties.isPoolPreparedStatements());
    druidDataSource.setMaxPoolPreparedStatementPerConnectionSize(properties.getMaxPoolPreparedStatementPerConnectionSize());

    try {
        druidDataSource.setFilters(properties.getFilters());
        druidDataSource.init();
    } catch (SQLException e) {
        e.printStackTrace();
    }

    return druidDataSource;
}

/**
 * 注册Servlet信息， 配置监控视图
 *
 * @return
 */
@Bean
@ConditionalOnMissingBean
public ServletRegistrationBean druidServlet() {
    ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(new StatViewServlet(), "/druid/*");

    //白名单：
    servletRegistrationBean.addInitParameter("allow","192.168.6.195");
    //IP黑名单 (存在共同时，deny优先于allow) : 如果满足deny的话提示:Sorry, you are not permitted to view this page.
    servletRegistrationBean.addInitParameter("deny","192.168.6.73");
    //登录查看信息的账号密码, 用于登录Druid监控后台
    servletRegistrationBean.addInitParameter("loginUsername", "admin");
    servletRegistrationBean.addInitParameter("loginPassword", "admin");
    //是否能够重置数据.
    servletRegistrationBean.addInitParameter("resetEnable", "true");
    return servletRegistrationBean;

}

/**
 * 注册Filter信息, 监控拦截器
 *
 * @return
 */
@Bean
@ConditionalOnMissingBean
public FilterRegistrationBean filterRegistrationBean() {
    FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean();
    filterRegistrationBean.setFilter(new WebStatFilter());
    filterRegistrationBean.addUrlPatterns("/*");
    filterRegistrationBean.addInitParameter("exclusions", "*.js,*.gif,*.jpg,*.png,*.css,*.ico,/druid/*");
    return filterRegistrationBean;
}

}