为什么选择 logback 而不是 log4j ？

• 非常自然的实现了SLF4J
• logback 需要包： slf4j-api，logback-core，logback-classic
• log4j 需要包：slf4j-api，slf4j-log4j12，log4j

一、配置
1、pom.xml

  <properties>
    <slf4j.version>1.7.2</slf4j.version>  
    <logback.version>1.2.17</logback.version>  
  </properties>
  ...
      <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>${slf4j.version}</version>
      </dependency>
      <dependency>
        <groupId>ch.qos.logback</groupId>
        <artifactId>logback-classic</artifactId>
        <version>${logback.version}</version>
      </dependency>
      <dependency>
        <groupId>ch.qos.logback</groupId>
        <artifactId>logback-core</artifactId>
        <version>${logback.version}</version>
      </dependency>

2、logback.xml
一般在 src/main/resources 下。
logback的具体细节 -> 点这里

<configuration>
  <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
    <!-- encoders are assigned the type
         ch.qos.logback.classic.encoder.PatternLayoutEncoder by default -->
    <encoder>
      <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
    </encoder>
  </appender>

  <root level="debug">
    <appender-ref ref="STDOUT" />
  </root>
</configuration>