skywalking-java/docs/en/setup/service-agent/java-agent

Setup java agent

1. Find agent folder in SkyWalking release package
2. Add -javaagent:/path/to/skywalking-package/agent/skywalking-agent.jar to JVM argument. And make sure to add it before the -jar argument.

New agent package looks like this：

+-- skywalking-agent
    +-- activations
         apm-toolkit-log4j-1.x-activation.jar
         apm-toolkit-log4j-2.x-activation.jar
         apm-toolkit-logback-1.x-activation.jar
         ...
    +-- config
         agent.config  
    +-- plugins
         apm-dubbo-plugin.jar
         apm-feign-default-http-9.x.jar
         apm-httpClient-4.x-plugin.jar
         .....
    skywalking-agent.jar

• Start your application.

Advanced features

• All plugins are in /plugins folder. The plugin jar is active when it is in there. Remove the plugin jar, it disabled.
• The default logging output folder is /logs.

Install javaagent FAQs

• Linux Tomcat 7, Tomcat 8
  Change the first line of tomcat/bin/catalina.sh.

CATALINA_OPTS="$CATALINA_OPTS -javaagent:/path/to/skywalking-agent/skywalking-agent.jar"; export CATALINA_OPTS

• Windows Tomcat 7, Tomcat 8
  Change the first line of tomcat/bin/catalina.bat.

set "CATALINA_OPTS=-javaagent:/path/to/skywalking-agent/skywalking-agent.jar"

• JAR file
  Add -javaagent argument to command line in which you start your app. eg:

java -javaagent:/path/to/skywalking-agent/skywalking-agent.jar -jar yourApp.jar

Supported middlewares, frameworks and libraries

See supported list.

Plugins

Java agent plugins are all pluggable. Optional plugins could be provided by source codes or in optional-plugins folder under agent. For using these plugins, you need to compile source codes by yourself, or copy the certain plugins to /plugins.

Now, we have the following known plugins.

• Trace Spring beans
• Trace Oracle and Resin
• Filter traces through custom services

Advanced Features

• Set the settings through system properties for config file override. Read setting override.
• Use gRPC TLS to link backend. See open TLS
• Monitor a big cluster by different SkyWalking services. Use Namespace to isolate the context propagation.
• Set client token if backend open token authentication.
• Application Toolkit, are a collection of libraries, provided by skywalking APM. Using them, you have a bridge between your application and skywalking APM agent.
  • If you want to use OpenTracing Java APIs, try SkyWalking OpenTracing compatible tracer. More details you could find at http://opentracing.io
  • If you want to print trace context(e.g. traceId) in your logs, choose the log frameworks, log4j, log4j2, logback
  • If you want to use annotations or SkyWalking native APIs to read context, try SkyWalking manual APIs
  • If you want to continue traces across thread manually, use across thread solution APIs.

Plugin Development Guide

SkyWalking java agent supports plugin to extend the supported list. Please follow our Plugin Development Guide.

Test

If you are interested in plugin compatible tests or agent performance, see the following reports.

• Plugin Test
• Java Agent Performance Test