一、新增需要的jar包

       去掉springboot專案自帶的日誌jar包，新增kafka和log4j的jar包

        <dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
			<exclusions>
				<exclusion>
					<groupId>org.springframework.boot</groupId>
					<artifactId>spring-boot-starter-logging</artifactId>
				</exclusion>
			</exclusions>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-log4j2</artifactId>
		</dependency>
		
		<dependency>
			<groupId>org.springframework.kafka</groupId>
			<artifactId>spring-kafka</artifactId>
		</dependency>
 

二、專案配置檔案（application.properties）新增log4j配置檔案

logging.config = classpath:log4j-spring-kafka.xml

三、log4j配置檔案

<?xml version="1.0" encoding="UTF-8"?>
<!-- Configuration後面的status，這個用於設定log4j2自身內部的資訊輸出，可以不設定，當設定成trace時， 你會看到log4j2內部各種詳細輸出。可以設定成OFF(關閉)或Error(只輸出錯誤資訊) -->
<Configuration status="OFF">
	<properties>
		<property name="kafka_bootstrap_servers">0.0.0.0:9092</property> 
		<property name="kafka_retries">3</property> 
		<property name="kafka_linger_ms">1000</property> <!-- 如果你想減少請求的數量，你可以將linger.ms設定為大於某個值的東西 -->
 		<property name="kafka_buffer_size">1048576</property>	<!-- 緩衝區大小 -->
 		<property name="kafka_buffer_memory">10485760</property> <!-- 控制生產者可用於緩衝的儲存器的總量 -->
	</properties>
	
	<Appenders>
		<!-- 輸出控制檯日誌的配置 -->
		<Console name="console" target="SYSTEM_OUT">
			<!--控制檯只輸出level及以上級別的資訊（onMatch），其他的直接拒絕（onMismatch） -->
			<ThresholdFilter level="DEBUG" onMatch="ACCEPT" onMismatch="DENY" />
			<!-- 輸出日誌的格式 -->
			<PatternLayout pattern="%d{yyyy-MM-dd HH:mm:ss SSS} [%t] %-5level %logger{36} - %msg%n" />
		</Console>
		
		<!-- syncSend指是否同步等待，設為false表示傳送訊息後立即返回,true則會等待kafka響應後返回 -->
		<Kafka name="buried" topic="buried" syncSend="false">  
		  <Filters>
		  	<MarkerFilter marker="buried" onMatch="ACCEPT" onMismatch="DENY"/>
		 	<ThresholdFilter level="INFO" onMatch="ACCEPT" onMismatch="DENY" />
		  </Filters>
		  <PatternLayout charset="UTF-8" pattern="%d{yyyy-MM-dd HH:mm:ss SSS} [%t] %-5level %logger{36} %marker - %msg%n"/>  
		  <Property name="bootstrap.servers" value="${kafka_bootstrap_servers}"/>
		  <Property name="retries" value="${kafka_retries}" />
		  <Property name="linger.ms" value="${kafka_linger_ms}" />
 		  <Property name="buffer.size" value="${kafka_buffer_size}" />
 		  <Property name="buffer.memory" value="${kafka_buffer_memory}" />
		</Kafka>
		
		<Kafka name="monitor" topic="monitor" syncSend="false">  
		  <Filters>
		  	<MarkerFilter marker="monitor" onMatch="ACCEPT" onMismatch="DENY"/>
		  	<ThresholdFilter level="INFO" onMatch="ACCEPT" onMismatch="DENY" />
		  </Filters>
		  <PatternLayout charset="UTF-8" pattern="%d{yyyy-MM-dd HH:mm:ss SSS} [%t] %-5level %logger{36} %marker - %msg%n"/>  
		  <Property name="bootstrap.servers" value="${kafka_bootstrap_servers}"/>
		  <Property name="retries" value="${kafka_retries}" />
		  <Property name="linger.ms" value="${kafka_linger_ms}" />
 		  <Property name="buffer.size" value="${kafka_buffer_size}" />
 		  <Property name="buffer.memory" value="${kafka_buffer_memory}" />
		</Kafka>
		
		<Async name="async">
			<AppenderRef ref="buried"/>
			<AppenderRef ref="monitor"/>
		</Async>
		
	</Appenders>
	<Loggers>
		<!-- name 必填且唯一 -->
	    <!-- level 設定輸出最低級別 預設error -->
	    <!-- additivity 是否在父Logger輸出, 預設 true -->
		<Logger name="com.start" level="trace" additivity="true">
			<AppenderRef ref="async" />
		</Logger>
		<!-- 必須包含一個 Root 元素 -->
		<Root level="debug">
			<AppenderRef ref="console" />
		</Root>
	</Loggers>
</Configuration>                                                                                                                                                                           
 

四、寫日誌

	protected static final Logger LOGGER = LogManager.getLogger(FlumeStartApplication.class);
	
	public static final Marker BURIED = MarkerManager.getMarker("buried");
    public static final Marker MONITOR = MarkerManager.getMarker("monitor");
	
	public static void main(String[] args) {
		SpringApplication.run(FlumeStartApplication.class, args);
		int i = 0;
		while (true) {
			i++;
			if (i%3 == 0) {
				LOGGER.info(BURIED,"BURIED埋點訊息{}", System.currentTimeMillis()/1000);
			} else if(i%3 == 1)  {
				LOGGER.debug(BURIED,"BURIED埋點訊息{}", System.currentTimeMillis()/1000);
			} else {
				LOGGER.info(MONITOR,"MONITOR監控訊息{}", System.currentTimeMillis()/1000);
			}
			
            try {
				Thread.sleep(2000);
				System.out.println("睡眠一會兒=======");
			} catch (InterruptedException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
        }
	}