com.newrelic.agent.instrumentation

Class GenericClassAdapter

java.lang.Object

org.objectweb.asm.ClassVisitor

com.newrelic.agent.instrumentation.GenericClassAdapter

public class GenericClassAdapter
extends org.objectweb.asm.ClassVisitor

We have two strategies for instrumenting methods. Each involves getting an InvocationHandler and calling InvocationHandler.invoke(Object, java.lang.reflect.Method, Object[]) to get a handler which is also an InvocationHandler. When the method finishes this handler will be invoked with the return value of the method or the exception if one was thrown. InvocationHandlerTracingMethodAdapter: If this is the first time a class is being loaded, a field of type InvocationHandler is created for every instrumented method. A static method is added which initializes these fields and this is called from the class initializer. These invocation handlers are factories which create the tracing invocation handler for the method, and they're created through a callback to PointCutClassTransformer.evaluate(Class, com.newrelic.agent.TracerService, Object, Object, Object, boolean, Object[]) . This is the faster of the two instrumentation approaches. ReflectionStyleClassMethodAdapter: If the class has already been loaded no fields can be added to it. In this case we fetch the tracer by making a call to AgentWrapper.invoke(Object, java.lang.reflect.Method, Object[]) passing in the invocation handler id ( see TracerService.getInvocationHandler(int).

Field Summary

Fields

Modifier and Type	Field and Description
protected java.lang.String	className

Fields inherited from class org.objectweb.asm.ClassVisitor

api, cv

Constructor Summary

Constructors

Constructor and Description
GenericClassAdapter(org.objectweb.asm.ClassVisitor cv, java.lang.ClassLoader classLoader, java.lang.String className, java.lang.Class<?> classBeingRedefined, java.util.Collection<PointCut> strongMatches, InstrumentationContext context)

Method Summary

Modifier and Type	Method and Description
java.util.List<PointCut>	getAppliedPointCuts()
java.util.Collection<com.newrelic.agent.instrumentation.AbstractTracingMethodAdapter>	getInstrumentedMethods()
void	visit(int version, int access, java.lang.String name, java.lang.String signature, java.lang.String superName, java.lang.String[] interfaces)
void	visitEnd()
org.objectweb.asm.MethodVisitor	visitMethod(int access, java.lang.String name, java.lang.String desc, java.lang.String signature, java.lang.String[] exceptions)

Methods inherited from class org.objectweb.asm.ClassVisitor

visitAnnotation, visitAttribute, visitField, visitInnerClass, visitModule, visitNestHost, visitNestMember, visitOuterClass, visitPermittedSubclass, visitRecordComponent, visitSource, visitTypeAnnotation

Methods inherited from class java.lang.Object

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

Field Detail

className

protected final java.lang.String className

Constructor Detail

GenericClassAdapter

public GenericClassAdapter(org.objectweb.asm.ClassVisitor cv,
                           java.lang.ClassLoader classLoader,
                           java.lang.String className,
                           java.lang.Class<?> classBeingRedefined,
                           java.util.Collection<PointCut> strongMatches,
                           InstrumentationContext context)

Method Detail

visit

public void visit(int version,
                  int access,
                  java.lang.String name,
                  java.lang.String signature,
                  java.lang.String superName,
                  java.lang.String[] interfaces)

Overrides:

visit in class org.objectweb.asm.ClassVisitor

visitMethod

public org.objectweb.asm.MethodVisitor visitMethod(int access,
                                                   java.lang.String name,
                                                   java.lang.String desc,
                                                   java.lang.String signature,
                                                   java.lang.String[] exceptions)

Overrides:

visitMethod in class org.objectweb.asm.ClassVisitor

visitEnd

public void visitEnd()

Overrides:

visitEnd in class org.objectweb.asm.ClassVisitor

getInstrumentedMethods

public java.util.Collection<com.newrelic.agent.instrumentation.AbstractTracingMethodAdapter> getInstrumentedMethods()

getAppliedPointCuts

public java.util.List<PointCut> getAppliedPointCuts()