com.newrelic.agent

Class Agent

java.lang.Object

com.newrelic.agent.Agent

public final class Agent
extends java.lang.Object

New Relic Agent class. The premain you see here is but a fleeting shadow of the true premain. The real premain, called directly by the JVM in response to the -javaagent flag, can be found in BootstrapAgent.java.

Field Summary

Fields

Modifier and Type	Field and Description
static IAgentLogger	LOG Access to logger.

Constructor Summary

Constructors

Constructor and Description
Agent()

Method Summary

Modifier and Type	Method and Description
static void	addMixinInterfacesToBootstrap(JarResource agentJarResource, java.net.URL agentJarUrl, java.lang.instrument.Instrumentation inst) Extract all the mixins from the Agent jar and add them to the bootstrap classloader.
static boolean	canFastPath() Return true if this Agent can use "fast path" optimizations.
static void	continuePremain(java.lang.String agentArgs, java.lang.instrument.Instrumentation inst, long startTime) Called by the "real" premain() in the BootstrapAgent.
static void	disableFastPath() Disable "fast path" optimizations for the lifetime of this Agent.
static long	getAgentPremainTimeInMillis()
static java.lang.String	getVersion()
static boolean	isDebugEnabled()
static void	main(java.lang.String[] args)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

LOG

public static final IAgentLogger LOG

Access to logger. Implementation note: logging is directed to the console until the AgentService is initialized by the ServiceManager. This occurs during ServiceManager.start(). Prior to initialization, the log level is INFO.

Constructor Detail

Agent

public Agent()

Method Detail

getVersion

public static java.lang.String getVersion()

isDebugEnabled

public static boolean isDebugEnabled()

canFastPath

public static boolean canFastPath()

Return true if this Agent can use "fast path" optimizations.

Returns:

true if this Agent can use "fast path" optimizations. Fast path optimizations cannot be enabled if certain legacy instrumentation is in use (and possibly for other reasons as well).

disableFastPath

public static void disableFastPath()

Disable "fast path" optimizations for the lifetime of this Agent.

continuePremain

public static void continuePremain(java.lang.String agentArgs,
                                   java.lang.instrument.Instrumentation inst,
                                   long startTime)

Called by the "real" premain() in the BootstrapAgent.

main

public static void main(java.lang.String[] args)

getAgentPremainTimeInMillis

public static long getAgentPremainTimeInMillis()

addMixinInterfacesToBootstrap

public static void addMixinInterfacesToBootstrap(JarResource agentJarResource,
                                                 java.net.URL agentJarUrl,
                                                 java.lang.instrument.Instrumentation inst)

Extract all the mixins from the Agent jar and add them to the bootstrap classloader. JAVA-609.

Implementation note: In addition to the mixin interfaces themselves, a small number of dependent classes are extracted into the generated jar and loaded on the bootstrap. These are marked with the LoadOnBootstrap annotation. One class so marked is the InterfaceMixin annotation class itself.

This method duplicates some of the functionality found in the ClassAppender class in the Weaver. This duplication is intentional. This code runs before bootstrap classpath setup is complete. Attempting to reuse the ClassAppender causes one or more classes to be loaded by the "wrong" classloader as described in the top comment to this class. This could be fixed, but would invite later failures during code maintenance if dependencies were re-introduced. It is safer to ensure that code used under these special conditions remains right here.

Parameters:

agentJarResource - the Agent's jar file, or a test jar file for unit testing.

agentJarUrl - the Agent's jar URL, or a test URL for unit testing.

inst - the JVM instrumentation interface, or a mock for unit testing.