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

Setup java agent

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

• Override settings through System.properties
• Direct uplink and disable naming discovery
• Open TLS
• Namespace Isolation
• Token Authentication
• Application Toolkit
  • Overview
  • Use SkyWalking OpenTracing compatible tracer
  • Integration with log frameworks
    • log4j
    • log4j2
    • logback
  • Trace by SkyWalking manual APIs
  • Trace across threads

Test

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

• Plugin Test
• Java Agent Performance Test