springboot将日志打印到指定文件

1、以eureka server启动类为例，将启动类改为以下内容：

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
import org.springframework.core.env.Environment;

/**
 * @author Administrator
 */
@SpringBootApplication
@EnableEurekaServer
public class EurekaApplication {
  private static final Logger LOG = LoggerFactory.getLogger(EurekaApplication.class);
  public static void main(String[] args) {
    SpringApplication app = new SpringApplication(EurekaApplication.class);
    Environment env = app.run(args).getEnvironment();
    LOG.info("Eureka启动成功,地址: 	http://{}:{}", env.getProperty("eureka.instance.hostname"), env.getProperty("server.port"));
  }

}

2、添加logback.xml，在logback.xml中加入以下内容：

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    <!-- 修改一下路径-->
    <property name="PATH" value="/Idea/log/course/eureka"></property>

    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
        <encoder>
                <Pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} %highlight(%-5level) %blue(%-50logger{50}:%-4line) %msg%n</Pattern>
<!--            <Pattern>%d{ss.SSS} %highlight(%-5level) %blue(%-30logger{30}:%-4line) %msg%n</Pattern>-->
        </encoder>
    </appender>

    <appender name="TRACE_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${PATH}/trace.log</file>
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <FileNamePattern>${PATH}/trace.%d{yyyy-MM-dd}.%i.log</FileNamePattern>
            <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
                <maxFileSize>10MB</maxFileSize>
            </timeBasedFileNamingAndTriggeringPolicy>
        </rollingPolicy>
        <layout>
            <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} %-5level %-50logger{50}:%-4line %green(%-8X{UUID}) %msg%n</pattern>
        </layout>
    </appender>

    <appender name="ERROR_FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>${PATH}/error.log</file>
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <FileNamePattern>${PATH}/error.%d{yyyy-MM-dd}.%i.log</FileNamePattern>
            <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
                <maxFileSize>10MB</maxFileSize>
            </timeBasedFileNamingAndTriggeringPolicy>
        </rollingPolicy>
        <layout>
            <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} %-5level %-50logger{50}:%-4line %green(%-8X{UUID}) %msg%n</pattern>
        </layout>
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
            <level>ERROR</level>
            <onMatch>ACCEPT</onMatch>
            <onMismatch>DENY</onMismatch>
        </filter>
    </appender>

    <root level="ERROR">
        <appender-ref ref="ERROR_FILE" />
    </root>

    <root level="TRACE">
        <appender-ref ref="TRACE_FILE" />
    </root>

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