com.newrelic.agent.instrumentation.weaver.preprocessors

Class AgentPreprocessors.TokenNullCheckClassVisitor

java.lang.Object

org.objectweb.asm.ClassVisitor

com.newrelic.agent.instrumentation.weaver.preprocessors.AgentPreprocessors.TokenNullCheckClassVisitor

Enclosing class:

AgentPreprocessors

public class AgentPreprocessors.TokenNullCheckClassVisitor
extends org.objectweb.asm.ClassVisitor

A visitor which detects simple cases where the user calls expire on a token but does not null the token out. In these cases the visitor will insert bytecode which nulls out the token. Bytecode which already nulls out the NewField will be unaffected. By nulling out the token, the newfield will be reset and be eligible for map removal. Example:

   token.link();
   token.expire(); // visitor detects expire
   token = null;   // visitor writes this (unless the user already did)

Field Summary

Fields inherited from class org.objectweb.asm.ClassVisitor

api, cv

Constructor Summary

Constructors

Constructor and Description
TokenNullCheckClassVisitor(int api, org.objectweb.asm.ClassVisitor cv)

Method Summary

Modifier and Type	Method and Description
java.util.Map<java.lang.String,java.lang.Integer>	getExpireRewriteCounts() For testing
void	visit(int version, int access, java.lang.String name, java.lang.String signature, java.lang.String superName, java.lang.String[] interfaces)
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

getDelegate, visitAnnotation, visitAttribute, visitEnd, 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

Constructor Detail

TokenNullCheckClassVisitor

public TokenNullCheckClassVisitor(int api,
                                  org.objectweb.asm.ClassVisitor cv)

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

getExpireRewriteCounts

public java.util.Map<java.lang.String,java.lang.Integer> getExpireRewriteCounts()

For testing