日志框架的使用

1、先进行一个简单的测试；
@RunWith(SpringRunner.class)
@SpringBootTest
public class LoggerTest
{
private final Logger logger = LoggerFactory.getLogger(LoggerTest.class);
@Test
public void test1() {
String name = “snail”;
String password = “123456”;
logger.debug(“debug…..”);
logger.info(“info……”);
logger.error(“error…..”);

        }
    }

    运行输出：
    2018-07-12 19:34:50,963 - Started LoggerTest in 9.757 seconds (JVM running for 10.57)
    2018-07-12 19:34:51,009 - info......
    2018-07-12 19:34:51,009 - error.....
    2018-07-12 19:34:51,009 - Closing org.springframework.web.context.support.GenericWebApplicationContext@36804139:
    startup date [Thu Jul 12 19:34:41 CST 2018]; root of context hierarchy
    2018-07-12 19:34:51,009 - Closing JPA EntityManagerFactory for persistence unit 'default'


    由上面可知，打印了info、error。为什么没有打印debug呢？因为日志默认基本是基本是info，在其之下的级别就没有输出。



    注意首先引入日志类：Logger，其中LoggerTest.class必须为当前类。但是每次都这样写有点麻烦，所有可是使用注解: @Slf4j

    @RunWith(SpringRunner.class)
    @SpringBootTest
    @Slf4j
    public class LoggerTest
    {

        @Test
        public void test1() {
            String name = "snail";
            String password = "123456";
            log.debug("debug.....");
            log.info("info......");
            log.error("error.....");

        }
    }


2、日志中输入变量：
@RunWith(SpringRunner.class)
@SpringBootTest
@Slf4j
public class LoggerTest
{

    @Test
    public void test1() {
        String name = "snail";
        String password = "123456";
        log.debug("debug.....");
        log.info("info......");
        log.error("error.....");

        log.info("name:"+name+"password:"+password);
        log.info("name: {} ,password: {}",name,password);

    }
}


3、基于application.yml文件的配置（进行简单的配置）

logging:
    pattern:
        #配置日志输出格式--日期 - 信息，换行
        console: "%d - %msg%n"

例如：
2018-07-12 19:49:23,440 - ClassTemplateLoader for Spring macros added to FreeMarker configuration
2018-07-12 19:49:23,652 - Started LoggerTest in 9.106 seconds (JVM running for 9.882)
2018-07-12 19:49:23,695 - info......
2018-07-12 19:49:23,695 - error.....
2018-07-12 19:49:23,695 - name:snailpassword:123456
2018-07-12 19:49:23,695 - name: snail ,password: 123456
2018-07-12 19:49:23,698 - Closing org.springframework.web.context.support.GenericWebApplicationContext@2235eaab: startup date [Thu Jul 12 19:49:15 CST 2018]; root of context hierarchy
2018-07-12 19:49:23,702 - Closing JPA EntityManagerFactory for persistence unit 'default'


logging:
  pattern:
  #配置日志输出格式--日期 - 信息，换行
    console: "%d - %msg%n"
    #日志输出的路径
  path: /var/log/tomcat



  logging:
  pattern:
  #配置日志输出格式--日期 - 信息，换行
    console: "%d - %msg%n"
    #指定名字和路径
  file: /var/log/tomcat/sell.log


  logging:
  pattern:
  #配置日志输出格式--日期 - 信息，换行
    console: "%d - %msg%n"
    #指定名字和路径
  file: /var/log/tomcat/sell.log
  #指定日志级别
  level: debug


logging:
  pattern:
  #配置日志输出格式--日期 - 信息，换行
    console: "%d - %msg%n"
    #指定名字和路径
  file: /var/log/tomcat/sell.log
  #指定具体类日志级别
  level: 
    com.snail.sell.service.LoggerTest: debug



4、基于logback-spring.xml的配置（可以进行较为复杂的配置）：例如
①区分info和error日志；
②每天产生一个日志；

Ⅰ、在resources目录下新建一个配置文件：logback-spring.xml
Ⅱ、配置内容如下：
<?xml version="1.0" encoding="UTF-8" ?>

<configuration>
    <!--控制台输出-->
    <appender name="consoleLog" class="ch.qos.logback.core.ConsoleAppender">
        <!--日志展示-->
        <layout class="ch.qos.logback.classic.PatternLayout">
           <!--具体的展示格式-->
            <pattern>
                %d - %msg%n
            </pattern>
        </layout>
    </appender>
    <!--文件日志配置-->
    <appender name="fileInfoLog" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <filter class="ch.qos.logback.classic.filter.LevelFilter">

            <level>ERROR</level>
            <onMatch>DENY</onMatch>
            <onMismatch>ACCEPT</onMismatch>
        </filter>
        <encoder>
            <pattern>
                %msg%n
            </pattern>
        </encoder>
        <!--滚动策略-->
        <!--按时间滚动，每天一个日志-->
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <!--路径-->


            <fileNamePattern>/var/log/tomcat/sell/info.%d.log</fileNamePattern>
        </rollingPolicy>
    </appender>

    <!--错误日志-->
    <appender name="fileErrorLog" class="ch.qos.logback.core.rolling.RollingFileAppender">
       <!--根据范围过滤日志，只输出error级别的日志-->
        <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
            <level>ERROR</level>
        </filter>
        <encoder>
            <pattern>
                %msg%n
            </pattern>
        </encoder>
        <!--滚动策略-->
        <!--按时间滚动，每天一个日志-->
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <!--路径-->
            <fileNamePattern>/var/log/tomcat/sell/error.%d.log</fileNamePattern>
        </rollingPolicy>
    </appender>
    <!--使用配置-->
    <root level="info">
        <appender-ref ref="consoleLog" />
        <appender-ref ref="fileInfoLog" />
        <appender-ref ref="fileErrorLog" />
    </root>

</configuration>