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We hate/love lambda

Javalobby Syndicated Feed - Tue, 15-Apr-14 23:00
We have the long waited lambda feature in Java 8. And we love it. We love to use it at places where we used anonymous class. We love to use it where we used some looping construct. Now we use functional interfaces instead and thus we get faster performance using parallel streams and we get more readable code. The time is a short period of euphoria to be replaced by the several, low orbiting WTFs...
Categories: Java

DZone Weekly Link Roundup (April 15)

Javalobby Syndicated Feed - Tue, 15-Apr-14 23:00
NEWS Chef Delivers DevOps Automation for Windows and Microsoft Azure Preview Text:  This week's link roundup includes Chef's new Microsoft Azure integrations, Cassandra hits one million writes per second, Hadoop has a new search engine, utilizing continuous delivery, the 30 best tools for data visualization, and an answer to why Unreal...
Categories: Java

JSF + AngularJS = AngularFaces?

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:30
In case you haven't noticed, there's a pretty big shakeup going on in the world of Web UIs. Powered by several factors, JavaScript/rich client frameworks like AngularJS appear to be presenting a serious challenge to the server-side stalwarts of JSF, Spring MVC and the like. What will happen in the long run is anybody's guess. Preview Text:  Powered...
Categories: Java

We're Hacking JDBC, so You Don't Have To

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:30
We love working with JDBCSaid no one. Ever. Preview Text:  "We love working with JDBC" - Said no one. Ever. Legacy Sponsored:  unsponsored
Categories: Java

Leadership essentials: Get on the green, then go for the hole

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:30
The sport of golf is a mathematician’s dream. Players succeed by getting ever closer to the objective. First, you hit the ball from the tee to some point partway down the course. Then you get a little closer with a second shot. Once on the green, you putt the ball towards the hole, getting still closer. And finally you complete the hole by sinking a final putt. Applying this iterative approach...
Categories: Java

Iconify: Simplified Icon Management for Android

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:30
Android developers don't need to be messing around with icons and image file types just to get an arrow button to look the way it should look - there are better things to do with your time. Preview Text:  Android developers don't need to be messing around with icons and image file types just to get an arrow button to look the way it should...
Categories: Java

“Incremental” Map/Reduce in MongoDB Isn’t

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:30
Rafal and Ben Foster commented on my previous post with some ideas on how to deal with incremental updates to map/reduce indexes. Rafal said: Actually, it's quite simple if you can 'reverse' the mapping operation (for given key find all documents matching that key): you just delete aggregate record with specified key and run incremental map-reduce on all matching documents. In today's example,...
Categories: Java

Why You Should Want to Use OpenStack

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:30
[This article was originally written by Nati Shalom.] Preview Text:  OpenStack is currently in a better position to have a good public/private cloud story that uses the same underlying infrastructure. This ties into what I previously discussed, regarding the reason you have public/private cloud offering based on OpenStack more than on any other...
Categories: Java

Circuit Breaker Pattern in Apache Camel

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:30
Camel is very often used in distributed environments for accessing remote resources. Remote services may fail for various reasons and periods. For services that are temporarily unavailable and recoverable after short period of time, a retry strategy may help. But some services can fail or hang for longer period of time making the calling application unresponsive and slow. Preview...
Categories: Java

Continuous Delivery: Visualized

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:30
For DZone's 2014 Guide to Continuous Delivery we created a detailed infographic to illustrate the creation of deployment pipelines. Preview Text:  For DZone's 2014 Guide to Continuous Delivery we created this detailed infographic to illustrate the creation of deployment pipelines. The Guide includes in-depth articles written by industry...
Categories: Java

Neo4j 2.0.2 Maintenance Release

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:30
Today we released the 2.0.2 maintenance release of Neo4j. This release comes with some critical stability improvements as well as a few small but handy Cypher type conversion functions. All Neo4j users are strongly recommended to upgrade to this release. Head on over to http://www.neo4j.org/download to upgrade to Neo4j 2.0.2. Neo4j 2.0.2 does not require any store-level upgrades from the...
Categories: Java

Innodb redo log archiving

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:30
This post was originally written by Vlad Lesin for the MySQL Performance Blog. Percona Server 5.6.11-60.3 introduces a new “log archiving” feature. Percona XtraBackup 2.1.5 supports “apply archived logs.” What does it mean and how it can be used? Preview Text:  Percona Server 5.6.11-60.3 introduces a new “log archiving” feature....
Categories: Java

Agile - What’s a Manager to Do?

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:30
Agile - What’s a Manager to Do? As a manager, when I first started learning about Agile development, I was confused by the fuzzy way that Agile teams and projects are managed (or manage themselves), and frustrated and disappointed by the negative attitude towards managers and management in general. Preview Text:  There are lots of management...
Categories: Java

Virtual Java User Group - Simple Concept with Quality Content

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:00
Virtual JUG is a simple concept based on the idea to organize a group that would generate quality content. Preview Text:  Virtual JUG is a simple concept based on the idea to organize a group that would generate quality content. Legacy Sponsored:  unsponsored ...
Categories: Java

Whose Function is It Anyway?

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:00
Whose Function Is It Anyway? For episode 0×20, we sit down with Bay Area improvisation trainer Chris Sams. Chris works with all sorts of organizations, including software development companies, teaching their teams in the art of applied improvisation. Most of us probably think of comedy troupes or shows such as Whose Line Is It Anyway when we think of improv, but improv skills can increase team...
Categories: Java

What is SaaS? What is PaaS?

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:00
 We're well out of the Web 2.0 days, and firmly in the world of SaaS and PaaS, but what does it mean? Preview Text:  SaaS or Software as a Service is a model of software delivery when all the software and data is stored in the "cloud". SaaS or Software as a Service is a model of software delivery when all the software and data is...
Categories: Java

Phabricator and NuoDB: Porting a PHP Application to a Distributed Database

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:00
This article was originally written by Philip Stoev IntroductionIn order to certify that NuoDB is a fully-featured database product that can be used to power existing enterprise-grade applications, we frequently migrate various pieces of software to run on NuoDB. Preview Text:  In order to...
Categories: Java

How SharePoint 2010 Customizations Can Be Mapped to SP 2013 App Model

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:00
I tried to do a mapping on h Preview Text:  This article includes a lengthy mapping on how the SharePoint 2010 server-side customization can be mapped to SP 2013 App Model. The full list is included in the article. Legacy Sponsored:  unsponsored
Categories: Java

WildFly System V Initial Script

Javalobby Syndicated Feed - Tue, 15-Apr-14 22:00
Here is WildFly application serverSystem V Initial Script that I quickly put together for a Centos 6 virtual machine. Use it at your own risk, don’t call me if something goes wrong, because I assume that you are an experienced Web Ops (web operations) or Sys Admin (system administrator) and you definitely know what you are doing. Here goes cat /etc/init.d/wildfly.sh: Preview...
Categories: Java

A Note on Netstat

codecentric Blog - Tue, 15-Apr-14 11:59

If you have been working with netstat on GNU/Linux for some time you’ve probably already noticed, that more often than not, applications that actually are used exclusively or almost exclusively via IPv4, show up as if we were using IPv6. A typical example is the Squid Proxy on xx.xxx.xx.xxx:3128 below:

$ netstat -tn
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address           Foreign Address         State
tcp        0      0 xx.xxx.xx.xxx:22        yyy.yyy.yyy.yy:56542    ESTABLISHED
tcp6       0      0 xx.xxx.xx.xxx:3128      yyy.yyy.yyy.yy:3134     ESTABLISHED

With xx.xxx.xx.xxx and yyy.yyy.yyy.yy being IPv4 addresses, two questions arise:

  1. Why are IPv4 connections tagged with tcp6 by netstat?
  2. What makes the SSH connection to xx.xxx.xx.xxx:22 different?


To answer these questions we have to make a brief excursion to the Linux Socket API. Using the socket() function we can either create

  • a plain old IPv4 socket,
  • an IPv6 socket,
  • or a dual mode IPv6 socket.

Dual mode IPv6 sockets handle IPv4 connections using IPv4-Mapped IPv6 Addresses. Unfortunately, at least on Linux, there seems to be no clean way to distinguish pure IPv6 from dual mode IPv6 sockets for outside programs. They both show up in /proc/net/tcp6, where netstat finds them and displays them accordingly. The status of plain old IPv4 sockets on the other hand, is made available to user space via /proc/net/tcp.

Using this information our two questions are easily answered:

  1. Information related to dual mode IPv6 sockets, as they are used by Squid, is tagged with tcp6.
  2. Information related to plain old IPv4 sockets, like the SSH connection above, is tagged with tcp.

Note that dual-mode sockets are not only supported by Linux, but by most modern operating systems. They are preferred by the Java socket implementation unless you set the system property java.net.preferIPv4Stack to true. I have written a small C program that demonstrates the different types of sockets discussed above. You can play around with it if you are interested in the gory details.

The post A Note on Netstat appeared first on codecentric Blog.

Categories: Agile, Java, TDD & BDD

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