@Override
        public byte[] doInTransform(Instrumentor instrumentor, ClassLoader classLoader, String className, Class<?> classBeingRedefined, ProtectionDomain protectionDomain, byte[] classfileBuffer) throws InstrumentException {
            InstrumentClass target = instrumentor.getInstrumentClass(classLoader, className, classfileBuffer);

            final InstrumentMethod constructor = target.getConstructor("java.lang.String");
            boolean transformed = false;
            if (constructor != null) {
                transformed = true;
                constructor.addScopedInterceptor(PatternLayoutInterceptor.class, "ModifyPattern");
            }
            InstrumentMethod setPattern = target.getDeclaredMethod("setConversionPattern", "java.lang.String");
            if (setPattern != null) {
                transformed = true;
                setPattern.addScopedInterceptor(PatternLayoutInterceptor.class, "ModifyPattern");
            }
            return transformed ? target.toBytecode() : null;
        }
This modifier support log4j 1.2.15 version, or greater.
Because under 1.2.15 version is not exist MDC function and the number of constructor is different
and under 1.2.15 version is too old.
For reference 1.2.14 version release on Sep. 2006.
Refer to url http://mvnrepository.com/artifact/log4j/log4j for detail.

@author minwoo.jung
agent-module/plugins/log4j/src/main/java/com/navercorp/pinpoint/plugin/log4j/Log4jPlugin.java