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Thu Apr 06 06:33:22 GMT 2023

java



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Sat Feb 20 13:10:54 GMT 2021 From /weblog/java/features

Graal


Java on Truffle — Going Fully Metacircular - https://medium.com[..]le-going-fully-metacircular-215531e3f840 https://www.infoq.cn/article/gTHX7fc0CLTtV9FCbGjO

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Sat Feb 13 14:24:00 GMT 2021 From /weblog/java/fundamental

crash


In this post we will be looking at crash logs, the hs_err file, that is generated when the Java Virtual Machine crashes. Trying to find what is going wrong, and which component to blame, is important to understand how to interpret the crash log file. The focus will be on understanding the frames that make up the stack trace. - https://inside.java/2021/02/12/deciphering-the-stacktrace/

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Sat Feb 13 14:17:38 GMT 2021 From /weblog/java/tools

monitoring


Java Flight Recorder, a tool to record all detail of how the API work for undo and replay and detail profiling - http://docs.oracle.com/cd/E15289_01/doc.40/e15070/toc.htm

Creating Custom JFR Events - http://hirt.se/blog/?p=444

Java Mission Control - http://blog.eisele.net[..]-mission-control-52-is-finally-here.html http://hirt.se/blog/?p=343 http://hirt.se/blog/?p=364&cpage=1#comment-98 https://www.infoq.com/news/2016/10/Java-Flight-Recorder-Mission

Support of JMX from common java library - http://www.javacodegeeks.com[..]ling-jmx-in-hibernate-ehcache-qurtz.html

sample code show how to get vm info at jmx - http://blogs.sun.com/jmxetc/entry/how_to_retrieve_remote_jvm

An excellent short tutorial of JMX - http://java.sun.com/developer/technicalArticles/J2SE/jmx.html

Monitoring all tomcat 5 JMX information, with free tools and java startup config - http://jroller.com[..]illiams/20050202#monitoring_tomcat_5_5_x

Task manager like jconsole plugin - http://blog.luminis.nl[..]is/entry/top_threads_plugin_for_jconsole

Performance cost of JMX - http://weblogs.java.net[..]nus/archive/2006/07/how_much_does_i.html

Monitoring Local and Remote Applications Using JMX 1.2 and JConsole - http://onjava.com/lpt/a/5226

Collections of tools - http://www.javacodegeeks.com[..]/client-side-server-monitoring-with.html

remote conenction with ssh - http://theholyjava.wordpress.com[..]nitoring-remote-jvm-over-ssh-jmx-or-not/

IBM healthcare API - http://www.ibm.com[..]rary/j-healthcareapi1/index.html?ca=drs- http://www.ibm.com/developerworks/java/jdk/tools/healthcenter/

JVM Statistics with jstat - http://marxsoftware.blogspot.hk[..]k/2017/05/jvm-statistics-with-jstat.html

Useful JDK tools - https://blog.marcinchwedczuk.pl/useful-jdk-tools-part-1

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Fri Feb 12 00:37:17 GMT 2021 From /weblog/java/fundamental

assemble


The tool that allow you write JVM instruction using assemble like command

http://jasclipse.sourceforge.net/

An article about assemble Java - http://www.theserverside.com[..]s/content/GuideJavaBytecode/article.html

Overview of bytecode - http://arhipov.blogspot.com[..]/2011/01/java-bytecode-fundamentals.html http://www.javaadvent.com/2013/12/mastering-java-bytecode.html https://blog.jamesdbloom.com/JavaCodeToByteCode_PartOne.html

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Thu Feb 04 13:57:57 GMT 2021 From /weblog/java/network

socket


Talking to Postgres Through Java 16 Unix-Domain Socket Channels - https://www.morling.dev[..]ugh-java-16-unix-domain-socket-channels/

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Wed Jan 06 12:49:46 GMT 2021 From /weblog/java/string

construction


Java's String.repeat Method in Action: Building PreparedStatement with Dynamic Number of Parameters - https://marxsoftware.blogspot.com[..]k11-string-repeat-preparedstatement.html

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Sun Dec 20 14:24:50 GMT 2020 From /weblog/java/performance

hotspot


How can jruby take advantage of hotspot - http://headius.blogspot.com[..]nderstanding-jvm-jit-and-helping-it.html

Discussion about OOME - http://www.codingthearchitecture.com[..]01/14/jvm_lies_the_outofmemory_myth.html

How hotspot optimization ofoptimzate Polymorphism - http://blogs.azulsystems.com/cliff/2008/03/another-round-o.html

List of tools - http://www.jroller.com/lmchung/entry/java_performance_tools

an issue of hotspot but haven't handle in 5 year - http://bugs.sun.com/view_bug.do?bug_id=6186134

A test for how hotspot inline method - http://java.dzone.com/articles/how-aggressive-method-inlining http://nurkiewicz.blogspot.com.au[..]ggressive-is-method-inlining-in-jvm.html

Various JIT optimization that JVM doing - http://blog.takipi.com[..]uper-useful-jit-optimization-techniques/

https://www.reddit.com[..]ava_as_fast_as_c_when_it_comes_to_stack/

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Wed Oct 14 04:11:16 GMT 2020 From /weblog/java/libraries

high performance


Reactor framework, base on disruptor - http://www.infoq.com/news/2013/11/reactor-goes-ga

One http library to consider, Comsat - http://blog.paralleluniverse.co/2015/12/02/http-clients/

disruptor 高性能队列最佳选择 - https://xie.infoq.cn/article/7cee25201ffdaba3b8644d68d?y=qun0825

Babl High-Performance WebSocket Server - https://epickrram.blogspot.com[..]l-high-performance-websocket-server.html https://github.com/babl-ws/babl

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Thu Oct 08 00:22:27 GMT 2020 From /weblog/java/features

JNI


Invoking Assembly Language Programs using java native interface - http://today.java.net/lpt/a/330

Best practices for using the Java Native Interface - http://www.ibm.com/developerworks/java/library/j-jni/index.html

Other library try to simple using native library - https://inside.java/2020/10/06/jextract/

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Wed Oct 07 13:11:17 GMT 2020 From /weblog/java/features

java15


https://www.infoq.com/news/2020/09/java15-released

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Wed Aug 26 06:25:14 GMT 2020 From /weblog/java/features

reflection


Good : dynamic, generic
Bad: slow, don't work with Obfuscators and most searching and refactoring tools

http://jroller.com/page/ie?entry=time_to_reconsider_reflection

A very nice tool to get parameter name - https://github.com/paul-hammant/paranamer (e.g.: user of getUser(User user))

How to improve the performance - http://coding-masters.blogspot.com[..]-reflection-as-fast-as-direct-calls.html

The problem of using reflection to modify final field - http://www.azulsystems.com[..]7-writing-to-final-fields-via-reflection

Using reflection for using test - http://www.javaadvent.com[..]f-hacking-enums-and-modifying-final.html

Sharing about using invokedynamic - http://www.infoq.com/presentations/invokedynamic http://www.infoq.com[..]ticles/Invokedynamic-Javas-secret-weapon https://www.infoq.com/articles/Invokedynamic-Javas-secret-weapon

LamdbaMetafactory is pretty fast. (*) - https://www.optaplanner.org[..]8/01/09/JavaReflectionButMuchFaster.html

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Tue Jul 14 06:44:05 GMT 2020 From /weblog/java/fundamental

object


We can control how the default hashcode return, and and what the difference of default hashcode between java7 and 8 - https://blog.codinghorror.com/complaint-driven-development/

http://sigpwned.com/2018/08/10/string-hashcode-is-plenty-unique/

https://shipilev.net/jvm/objects-inside-out

https://www.baeldung.com/jvm-measuring-object-sizes

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Mon Jun 08 16:02:20 GMT 2020 From /weblog/java/discussion

books


http://www.javalobby.org/articles/5books/

https://handwiki.org/wiki/Book:ThinkJava

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Wed Jun 03 07:55:56 GMT 2020 From /weblog/java/discussion

VM


How to write a (toy) JVM - https://zserge.com/posts/jvm/

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Tue Jun 02 02:14:05 GMT 2020 From /weblog/java/libraries

math


Efficient Java Matrix Library (EJML) is a linear algebra library for manipulating real/complex/dense/sparse matrices. Its design goals are; 1) to be as computationally and memory efficient as possible for both small and large matrices, and 2) to be accessible to both novices and experts. These goals are accomplished by dynamically selecting the best algorithms to use at runtime, clean API, and multiple interfaces. EJML is free, written in 100% Java and has been released under an Apache v2.0 license. - http://ejml.org/wiki/index.php?title=Main_Page

https://mkyong.com/java/java-mod-examples

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Tue Jun 02 00:32:20 GMT 2020 From /weblog/java/features

java14


http://cr.openjdk.java.net[..]jlaskey/Strings/TextBlocksGuide_v10.html

https://ondro.inginea.eu[..]new-features-between-java-8-and-java-14/

JDK 14 Foreign-Memory Access API Overview - https://medium.com[..]-memory-access-api-overview-70951fe221c9

Pattern Matching for instanceof in Java 14 - https://blogs.oracle.com[..]ttern-matching-for-instanceof-in-java-14

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Tue Jun 02 00:30:26 GMT 2020 From /weblog/java/features

unsafe


The infamous sun.misc.Unsafe explained: object creation, native memory allocation, native concurrency - http://mydailyjava.blogspot.hk/2013/12/sunmiscunsafe.html

Features that help for writing low latency application - http://vanillajava.blogspot.com[..]1/sunmiscunsafe-and-off-heap-memory.html

Tips of using unsafe - http://vanillajava.blogspot.com.au[..].com.au/2014/06/making-unsafe-safer.html

An overview of it - http://www.infoq.com[..]A-Post-Apocalyptic-sun.misc.Unsafe-World https://blogs.oracle.com[..]ine/the-unsafe-class-unsafe-at-any-speed

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Mon Apr 06 13:51:19 GMT 2020 From /weblog/java/network

URI


https://blog.sebastian-daschner.com[..]om/entries/creating-uris-with-uribuilder

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Sun Mar 29 10:15:44 GMT 2020 From /weblog/java/concurrency

collections


Even though

private List synchList = Collections.synchronizedList(new LinkedList());

is thread safe, serialize sync List is NOT thread safe for sure. The story is, if you only synchronized the collection, and if we try to get the iterator in concurrent access environment, it will throws currencymodificationexception .

For collection is small, may be making defensive copy http://www.javapractices.com/Topic15.cjp is good. Otherwise, in java5, there is concurrency collection.

reference:
http://jroller.com[..]ntry=collections_synchronizedlist_broken
http://jroller.com/page/ctarrington?entry=java_collections_trivia

Map operation, include use of FutureTask and putIfAbsent() method from ConcurrentMap. - http://www.javaspecialists.co.za/archive/newsletter.do?issue=125

Other then lterate through the elements, adding and removing elements can also be problem, this article document a few good cases about that - http://rayfd.wordpress.com[..]en-a-synchronized-class-isnt-threadsafe/

Samples of using Queue.drainTo() - http://binkley.blogspot.com[..]rforming-fixed-amounts-of-work-with.html

http://tech.puredanger.com/2009/02/28/java-7-transferqueue/

Overview of blockingqueue - http://tutorials.jenkov.com[..]/java-util-concurrent/blockingqueue.html

Simple benchmark - http://java-persistence-performance.blogspot.com[..]jvm-performance-part-iii-concurrent.html

Multi-thread behaviour - http://vanillajava.blogspot.com[..]hread-safety-issues-with-vector-and.html

java.util.concurrent.ConcurrentHashMap VS openhft.collections.SharedHashMap - http://openhft.blogspot.co.uk[..]autilconcurrentconcurrenthashmap-vs.html

Why are there so many concurrent queues implementations in Java? - https://vmlens.com/articles/cp/why_so_many_queues/

Why hashmap is not thread safe - https://www.pixelstech.net[..]a-HashMap-is-considered-as-thread-unsafe

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Mon Feb 10 23:05:49 GMT 2020 From /weblog/java/fundamental

time


How difference platform implement nanoTime() - http://www.javacodegeeks.com[..]12/02/what-is-behind-systemnanotime.html http://stackoverflow.com[..]62/is-system-nanotime-completely-useless

Java timezone ID reference - http://david.uebelacker.ch[..]etrive-locale-and-timezone-from-request/ http://tutorials.jenkov.com[..]m/java-date-time/java-util-timezone.html

setTimeZone affects calls to set(), but doesn’t change the existing Calendar time? So if we wanted to change the time zone we are working with, we have to adjust all the time fields too…but a SimpleDateFormatter still would show it as the current time zone. - http://keyholesoftware.wordpress.com[..]1/joda-time-the-future-of-java-datetime/

http://blog.joda.org[..]va-time-jsr-310-enhancements-java-9.html

deep dive into measuring time in Java - dihttps:[..]g-time-from-java-to-kernel-and-back.html

CronScheduler - https://medium.com[..]r-for-external-interactions-cb7ce4a4f2cd

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Tue Jan 28 10:48:00 GMT 2020 From /weblog/java/concurrency

tutorial


Another nice tutorial set of concurrency framework - http://www.javacodegeeks.com/search/label/Concurrency

Java concurrency, Building and testing concurrent applications for the Java platform - http://www.ibm.com[..]/training/kp/j-kp-concurrency/index.html

JVM concurrency: Java and Scala concurrency basics - http://www.ibm.com[..]/java/library/j-jvmc1/index.html?ca=drs-

http://javarevisited.blogspot.com.au[..]reading-interview-questions-answers.html

5 things you didn't know about ... Multithreaded Java programming - https://www.ibm.com/developerworks/library/j-5things15

266Threading Questions in Job Interviews (2/2) - https://www.javaspecialists.eu/archive/Issue266.html

Parallel Collection Processing: Without Parallel Streams - https://4comprehension.com/parallel-collection-processing-1/

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