Apache Camel日志组件示例

您要将消息记录到底层的记录机制，请使用骆驼的log:组件。 Camel使用sfl4j作为记录器API，然后允许您配置记录器实现。在本文中，我们将使用Log4j作为实际的记录器机制。让我们从示例开始。

依存关系

您需要添加：

slf4j-api – SLF4J Logger API
slf4j-log4j12 – Log4j作为记录器的实现

pom.xml：

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><groupId>com.javarticles.camel</groupId><artifactId>camelHelloWorld</artifactId><version>0.0.1-SNAPSHOT</version><dependencies><dependency><groupId>org.apache.camel</groupId><artifactId>camel-core</artifactId><version>2.15.1</version></dependency><dependency><groupId>org.apache.camel</groupId><artifactId>camel-stream</artifactId><version>2.15.1</version></dependency><dependency><groupId>org.apache.camel</groupId><artifactId>camel-jms</artifactId><version>2.15.1</version></dependency><dependency><groupId>org.apache.activemq</groupId><artifactId>activemq-camel</artifactId><version>5.6.0</version></dependency><dependency><groupId>org.springframework</groupId><artifactId>spring-context</artifactId><version>4.1.5.RELEASE</version></dependency><dependency><groupId>org.apache.camel</groupId><artifactId>camel-spring</artifactId><version>2.15.1</version></dependency><dependency><groupId>org.slf4j</groupId><artifactId>slf4j-api</artifactId><version>1.7.12</version></dependency><dependency><groupId>org.slf4j</groupId><artifactId>slf4j-log4j12</artifactId><version>1.7.12</version></dependency></dependencies>
</project>

日志组件URI格式

日志的uri格式：

log:loggingCategory[?options]

您可以使用选项来设置级别或格式设置选项。例如：

log:com.javarticles?level=INFO

在我的log4.properties中，root logger记录到文件以及控制台，而它仅记录com.javarticles类别的文件。 log4j.properties：

# Root logger option
log4j.rootLogger=INFO, file, consolelog4j.logger.com.javarticles=INFO, file# Direct log messages to a log file
log4j.appender.file=org.apache.log4j.FileAppender
log4j.appender.file.File=javarticles.log
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d | %p | %F %L | %m%n# Direct log messages to stdout
log4j.appender.console=org.apache.log4j.ConsoleAppender
log4j.appender.console.Target=System.out
log4j.appender.console.layout=org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern=%d{HH:mm}| %p | %F %L | %m%n

骆驼原木组件示例

CamelLog示例：

package com.javarticles.camel.components;import org.apache.camel.CamelContext;
import org.apache.camel.ProducerTemplate;
import org.apache.camel.builder.RouteBuilder;
import org.apache.camel.impl.DefaultCamelContext;
import org.apache.camel.util.jndi.JndiContext;public class CamelLogExample {public static final void main(String[] args) throws Exception {JndiContext jndiContext = new JndiContext();jndiContext.bind("stringUtils", new StringUtils());CamelContext camelContext = new DefaultCamelContext(jndiContext);try {camelContext.addRoutes(new RouteBuilder() {public void configure() {from("direct:logExample").log("Before converting to uppercase").to("log:?level=INFO&showBody=true").to("bean:stringUtils?method=upperCase").log("After converting to uppercase").to("log:com.javarticles?level=INFO&showAll=true");}});ProducerTemplate template = camelContext.createProducerTemplate();camelContext.start();template.sendBody("direct:logExample", "Log me!");} finally {camelContext.stop();}}
}

输出：

12:09| INFO | DefaultCamelContext.java 2454 | Apache Camel 2.15.1 (CamelContext: camel-1) started in 0.307 seconds
12:09| INFO | MarkerIgnoringBase.java 95 | Before converting to uppercase
12:09| INFO | MarkerIgnoringBase.java 95 | Exchange[ExchangePattern: InOnly, BodyType: String, Body: Log me!]
12:09| INFO | MarkerIgnoringBase.java 95 | After converting to uppercase
12:09| INFO | MarkerIgnoringBase.java 95 | Exchange[Id: ID-INMAA1-L1005-54363-1431153589693-0-2, ExchangePattern: InOnly, Properties: {CamelCreatedTimestamp=Sat May 09 12:09:50 IST 2015, CamelMessageHistory=[DefaultMessageHistory[routeId=route1, node=log1], DefaultMessageHistory[routeId=route1, node=to1], DefaultMessageHistory[routeId=route1, node=to2], DefaultMessageHistory[routeId=route1, node=log2], DefaultMessageHistory[routeId=route1, node=to3]], CamelToEndpoint=log://com.javarticles?level=INFO&showAll=true}, Headers: {breadcrumbId=ID-INMAA1-L1005-54363-1431153589693-0-1}, BodyType: String, Body: LOG ME!, Out: null: ]
12:09| INFO | DefaultCamelContext.java 2660 | Apache Camel 2.15.1 (CamelContext: camel-1) is shutting down

自定义Exchange格式化程序

如果您在上面的日志中注意到，即使对于showBody=true情况，它也会打印有效负载以及与交换相关的属性，例如ExchangePattern和BodyType 。我们可以自定义想要在日志中看到的内容。让我们看看如何实现它。通过实现ExchangeFormatter接口来实现自定义格式器类。从Exchange对象中选择我们要记录的元素。在我们的自定义交换格式器中，我们只想查看有效负载文本，因此format(Exchange)返回的是入站请求消息。 MyExchangeFormatter：

package com.javarticles.camel.components;import org.apache.camel.Exchange;
import org.apache.camel.spi.ExchangeFormatter;public class MyExchangeFormatter implements ExchangeFormatter {public String format(Exchange exchange) {return exchange.getIn().getBody(String.class);}}

您需要将foamtter对象与键logFormatter 。

jndiContext.bind("logFormatter", new MyExchangeFormatter());

CamelLogExchangeFormatter示例：

package com.javarticles.camel.components;import org.apache.camel.CamelContext;
import org.apache.camel.ProducerTemplate;
import org.apache.camel.builder.RouteBuilder;
import org.apache.camel.impl.DefaultCamelContext;
import org.apache.camel.util.jndi.JndiContext;public class CamelLogExchangeFormatterExample {public static final void main(String[] args) throws Exception {JndiContext jndiContext = new JndiContext();jndiContext.bind("stringUtils", new StringUtils());jndiContext.bind("logFormatter", new MyExchangeFormatter());CamelContext camelContext = new DefaultCamelContext(jndiContext);try {camelContext.addRoutes(new RouteBuilder() {public void configure() {from("direct:logExample").log("Before converting to uppercase").to("log:?level=INFO").to("bean:stringUtils?method=upperCase").log("After converting to uppercase").to("log:com.javarticles?level=INFO");}});ProducerTemplate template = camelContext.createProducerTemplate();camelContext.start();template.sendBody("direct:logExample", "Log me!");} finally {camelContext.stop();}}
}

StringUtils：

package com.javarticles.camel.components;public class StringUtils {public String upperCase(String msg) {return msg.toUpperCase();}
}

输出：

14:28| INFO | MarkerIgnoringBase.java 95 | Before converting to uppercase
14:28| INFO | MarkerIgnoringBase.java 95 | Log me!
14:28| INFO | MarkerIgnoringBase.java 95 | After converting to uppercase
14:28| INFO | MarkerIgnoringBase.java 95 | LOG ME!

吞吐量记录器示例

消息（本例中为数字）被发送到activemq队列numbers ，路由中的下一个目标将每10秒记录一次消息统计信息。使用groupInterval=10000选项配置间隔。

<route><from uri="activemq:queue:numbers" /><to uri="log:com.javarticles?level=INFO&groupInterval=10000" />
</route>

applicationContext.xml：

<?xml version="1.0" encoding="UTF-8"?><beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsdhttp://camel.apache.org/schema/spring http://camel.apache.org/schema/spring/camel-spring.xsd"><bean id="connectionFactory" class="org.apache.activemq.ActiveMQConnectionFactory"><property name="brokerURL" value="vm://localhost?broker.persistent=false" /></bean><bean id="activemq" class="org.apache.activemq.camel.component.ActiveMQComponent"><property name="connectionFactory" ref="connectionFactory" /></bean><camelContext xmlns="http://camel.apache.org/schema/spring"><route><from uri="activemq:queue:numbers" /><to uri="log:com.javarticles?level=INFO&groupInterval=10000" /></route></camelContext>
</beans>

CamelThroughputLogger示例：

package com.javarticles.camel.components;import org.apache.camel.CamelContext;
import org.apache.camel.ProducerTemplate;
import org.apache.camel.spring.SpringCamelContext;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;public class CamelThroughputLoggerExample {public static final void main(String[] args) throws Exception {ApplicationContext appContext = new ClassPathXmlApplicationContext("applicationContext.xml");CamelContext camelContext = SpringCamelContext.springCamelContext(appContext, false);try {ProducerTemplate template = camelContext.createProducerTemplate();camelContext.start();         for (int i = 0; i <18000; i++) {template.sendBody("activemq:queue:numbers", i);}Thread.sleep(10000);} finally {camelContext.stop();}}
}

输出：

19:04| INFO | MarkerIgnoringBase.java 95 | Received: 281 new messages, with total 281 so far. Last group took: 470 millis which is: 597.872 messages per second. average: 597.872
19:04| INFO | MarkerIgnoringBase.java 95 | Received: 14802 new messages, with total 15083 so far. Last group took: 10001 millis which is: 1,480.052 messages per second. average: 1,440.455
19:05| INFO | MarkerIgnoringBase.java 95 | Received: 2917 new messages, with total 18000 so far. Last group took: 10000 millis which is: 291.7 messages per second. average: 879.293

下载源代码

这是一个关于骆驼原木组件的例子。您可以在此处下载源代码： camelLogComponentExamples.zip

翻译自: https://www.javacodegeeks.com/2015/05/apache-camel-log-component-examples.html