Spring Boot入门第三天：配置日志系统和Druid数据库连接池。

原文链接

一、日志管理

1.在application.properties文件中加入如下内容：

logging.level.root=WARN
logging.level.org.springframework.web=DEBUG
logging.file=/log/log/my.log
logging.pattern.console=%d{yyyy-MM-dd HH:mm:ss} [%thread] %-5level %logger- %msg%n
logging.pattern.file=%d{yyyy-MM-dd HH:mm:ss} [%thread] %-5level %logger- %msg%n

设置了日志输出的级别，以及生成日志文件。再简单一点的话，最后两行也可以不要。

2.使用slf4j日志框架：

private static final Logger LOGGER = LoggerFactory.getLogger(UserController.class);

LOGGER.warn("您执行了UserController类中的userList2()方法。");

好了，不能写太多了。

二、配置Druid

1.在pom.xml文件中添加druid依赖：

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.0.26</version>
        </dependency>

2.添加配置类，直接拷贝了别人的代码：

package com.yws710.springboot.demo1;

import com.alibaba.druid.support.http.StatViewServlet;
import com.alibaba.druid.support.http.WebStatFilter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
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 java.util.HashMap;
import java.util.Map;

@Configuration
public class DruidConfiguration {

    private static final Logger LOGGER = LoggerFactory.getLogger(DruidConfiguration.class);

    @Bean
    public ServletRegistrationBean druidServlet() {
        LOGGER.info("init Druid Servlet Configuration ");
        ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean();
        servletRegistrationBean.setServlet(new StatViewServlet());
        servletRegistrationBean.addUrlMappings("/druid/*");
        Map<String, String> initParameters = new HashMap<String, String>();
        initParameters.put("loginUsername", "admin");// 用户名
        initParameters.put("loginPassword", "admin");// 密码
        initParameters.put("resetEnable", "false");// 禁用HTML页面上的“Reset All”功能
        initParameters.put("allow", ""); // IP白名单 (没有配置或者为空，则允许所有访问)
        //initParameters.put("deny", "192.168.20.38");// IP黑名单 (存在共同时，deny优先于allow)
        servletRegistrationBean.setInitParameters(initParameters);
        return servletRegistrationBean;
    }

    @Bean
    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;
    }

　　@Bean
　　@ConfigurationProperties(prefix="spring.datasource")
　　　　public DataSource druidDataSource() {
　　　　return new DruidDataSource();
　　}

}

3.添加配置文件，打开application.properties文件，加入如下代码：

##Druid##
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/demo1?characterEncoding=UTF-8
spring.datasource.username=root
spring.datasource.password=123456

spring.datasource.initialSize=5
spring.datasource.minIdle=5
spring.datasource.maxActive=20
spring.datasource.maxWait=60000
spring.datasource.timeBetweenEvictionRunsMillis=60000
spring.datasource.minEvictableIdleTimeMillis=300000
spring.datasource.validationQuery=SELECT 1 FROM DUAL
spring.datasource.testWhileIdle=true
spring.datasource.testOnBorrow=false
spring.datasource.testOnReturn=false
spring.datasource.poolPreparedStatements=true
spring.datasource.maxPoolPreparedStatementPerConnectionSize=20
spring.datasource.filters=stat,wall,log4j
spring.datasource.connectionProperties=druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
spring.datasource.useGlobalDataSourceStat=true

spring.jpa.properties.hibernate.hbm2ddl.auto=update
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5InnoDBDialect
spring.jpa.show-sql= true

参考：https://github.com/alibaba/druid/

4.启动项目。在浏览器地址栏中输入http://localhost:8080/druid/

由于上面配置了用户名和密码，因此需要登录：

登录成功后的页面就不截图了，用过Druid的自然知道，没用过的赶紧用啊，这么好的东西。