Hi Devs, Here is the detailed information about the things I am working on for performance optimization in our OFBiz code.
*1.) Downsize Accessibility Scope* I've tried to downsize accessibility scope of classes, interfaces, abstract class, declared member variables, enumerations, methods, and constructors to as minimum as possible as per OFBIz current implementation, still there is a lot of scope for improvement but it would require changes at the granular level. I've used this <https://docs.oracle.com/javase/tutorial/java/javaOO/accesscontrol.html> as my reference point. example: - public void noteKeyRemoval(UtilCache<K, V> cache, K key, V oldValue); + void noteKeyRemoval(UtilCache<K, V> cache, K key, V oldValue); Limiting the scope of the method from public modifier to package level. *2.) Using Lambda Expressions* Then tried to use lambda expressions on simple functional work to leverage implicit type of coding an example: - Map<String, String> initParameters = new LinkedHashMap<>(); - for (Element e : initParamList) { - initParameters.put(e.getAttribute("name"), e.getAttribute("value")); - } + Map<String, String> initParameters = initParamList.stream().collect(Collectors.toMap(e -> e.getAttribute("name"), e -> e.getAttribute("value"), (a, b) -> b, LinkedHashMap::new)); Some of the key benefits of using lambdas will introduce Functional style over Imperative style <https://stackoverflow.com/questions/2078978/functional-programming-vs-object-oriented-programming>, we can use method referencing <https://docs.oracle.com/javase/tutorial/java/javaOO/methodreferences.html>, usage of aggregate operations, and it will help developers to write memory efficient code. *3.) Using Type Inference* Java uses type inference so to make code lightweight I've updated code constructs as shown in the example for more on this refer this article <https://docs.oracle.com/javase/tutorial/java/generics/genTypeInference.htmlv> . - Map<String, ? extends Object> systemProps = UtilGenerics.<String, Object> checkMap(System.getProperties()); + Map<String, ?> systemProps = UtilGenerics.checkMap(System.getProperties()); *4.) Use of single quote for character* There is a significant usage of <"Single Character"> in the codebase for example: - throw new GenericConfigException("Error opening file at location [" + fileUrl.toExternalForm() + "]", e); + throw new GenericConfigException("Error opening file at location [" + fileUrl.toExternalForm() + ']', e); "]" is comparativlelly slower then ']' Java internally uses Flyweight Design pattern to create String literals so for every call it will not create a new Object and used an existing one this will improve performace to some extend an study can be seen on this <https://stackoverflow.com/questions/24859500/concatenate-char-literal-x-vs-single-char-string-literal-x> page. *5.) Updated Variable Declaration* Lastly some of the variable declaration is updated this doesn't create a huge difference but helps JVM at the from implicit conversion. - private long cumulativeEvents = 0; + private long cumulativeEvents = 0L; Based on above findings, I have done some code improvement and provided following patches. *And need community help for reviewing these changes.* Kindly provide any improvents or suggestion you have in mind :) 1. [OFBIZ-10344] Refactoring Variable Scope for org.apache.ofbiz.base package <https://issues.apache.org/jira/browse/OFBIZ-10344> 2. [OFBIZ-10345] Refactoring Variable Scope for org.apache.ofbiz.catalina.container <https://issues.apache.org/jira/browse/OFBIZ-10345> 3. [OFBIZ-10346] Refactoring Variable Scope for org.apache.ofbiz.common <https://issues.apache.org/jira/browse/OFBIZ-10346> 4. [OFBIZ-10347] Refactoring Variable Scope for org.apache.ofbiz.datafile <https://issues.apache.org/jira/browse/OFBIZ-10347> 5. [OFBIZ-10348] Refactoring Variable Scope for org.apache.ofbiz.entity <https://issues.apache.org/jira/browse/OFBIZ-10348> P.S. Apart from this I am also working on performance matrix and will share it soon. Thanks & Regards, -- *Pradhan Yash Sharma* On Tue, Apr 17, 2018 at 11:28 AM, Yash Sharma <yash.sha...@hotwaxsystems.com > wrote: > Thank you for the feedback I've created a Jira ticket OFBIZ-10343 > <https://issues.apache.org/jira/browse/OFBIZ-10343> and I will add > patches for the same for your review. > > Thanks & Regards, > -- > *Pradhan Yash Sharma* > > On Fri, Apr 13, 2018 at 5:50 PM, Taher Alkhateeb < > slidingfilame...@gmail.com> wrote: > >> Hello Pradhan, >> >> Refactoring is exactly what we need and is a welcomed activity. I >> think we should, however, try to avoid "big ideas" across the entire >> code base. The subject of your message is the reason why I say that. >> >> So, if you want to start refactoring, I suggest to start with one >> piece of code, study it careful, issue a JIRA, and provide a patch. >> This should be focused similar to your notes on UtilCache. >> >> On Fri, Apr 13, 2018 at 12:14 PM, Pradhan Yash Sharma >> <pradhanyashsharm...@gmail.com> wrote: >> > Hello, >> > >> > While I was working on UtilCache.java file came across some >> improvements, >> > they are as follows: >> > >> > 1) Method and Variable access modifiers can be narrowed down to private >> > access modifier. >> > >> > 2) Then AtomicLong can be given value 0L instead of 0. >> > >> > 3) Some Variables is used in both synchronized and unsynchronized >> blocks, >> > so they can be declared final. eg, >> > >> > >> > >> > *protected AtomicLong hitCount = new AtomicLong(0); >> private >> > final AtomicLong hitCount = new AtomicLong(0L);* >> > One variable was able to get most of my attention is >> > >> > * protected ConcurrentMap<Object, CacheLine<V>> >> memoryTable >> > = null;* >> > >> > This is used in synchronized and unsynchronized blocks, this Object can >> be >> > converted into ThreadLocal or AtomicReference but it would require >> changes >> > in the current implementation as well. >> > >> > Lastly, there is extensive use of for loops for iteration we can use >> Java 8 >> > Streams, Collector, and other functions to leverage implicit looping >> > mechanism. >> > >> > >> > -- >> > Pradhan Yash Sharma >> > >
