ByteBuddy agent

[wsargent]

Set up byte buddy agent to instrument built in classes.

public class PreloadedInstrumentationExample {
    public static void main(String[] args) throws Exception {
        Thread thread = Thread.currentThread();
        thread.run();
    }
}

application.conf:

logback.bytebuddy {
  classNames = ["java.lang.Thread"]

  methodNames = ["run"]
}

and logback-test.xml:

<configuration>
    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
        <encoder>
            <pattern>%-5relative %-5level %logger{35} - %msg%n</pattern>
        </encoder>
    </appender>

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

Then running with the java agent loaded:

'-Dconfig.file=/home/wsargent/work/terse-logback/logback-bytebuddy/src/test/resources/application.conf',
'-Dlogback.configurationFile=/home/wsargent/work/terse-logback/logback-bytebuddy/src/test/resources/logback-test.xml',
'-javaagent:lib/logback-bytebuddy-0.0.0.jar',

results in:

[Byte Buddy] DISCOVERY java.lang.Thread [null, null, loaded=true]
[Byte Buddy] TRANSFORM java.lang.Thread [null, null, loaded=true]
[Byte Buddy] COMPLETE java.lang.Thread [null, null, loaded=true]
92    TRACE java.lang.Thread - entering: java.lang.Thread.run() with arguments=[]
93    TRACE java.lang.Thread - exiting: java.lang.Thread.run() with arguments=[] => returnType=void