Apache web server running on an Amazon Elastic Compute Cloud (Amazon EC2) Linux instance is intermittently unresponsive and freezing. After checking log file:
$ sudo su
$ vi /var/log/messages
Out of memory error was found.
We finished the project for Maxi Kids furniture distributor in Chicagoland:
maxikidffurniture.com
The package java.concurrent.atomic
contains many useful classes to perform atomic operations. An operation is atomic when you can safely perform the operation in parallel on multiple threads without using the synchronized
keyword or locks as shown in the previous article.
In the previous article we've learned how to execute code in parallel via executor services. When writing such multi-threaded code you have to pay particular attention when accessing shared mutable variables concurrently from multiple threads. Let's just say we want to increment an integer which is accessible simultaneously from multiple threads.
MoreThe Concurrency API was first introduced with the release of Java 5 and then progressively enhanced with every new Java release. The majority of concepts shown in this article also work in older versions of Java. However my code samples focus on Java 8 and make heavy use of lambda expressions and other new features.
MoreOur task is service checking and restart that service if it's not running.
MoreIn general terms, functional programming is a programming paradigm, and it’s about programming with functions. What functional programming may be opposed to is the imperative programming paradigm. In imperative programming style, programs are composed from elements that “do” something. “Doing” something generally implies an initial state, a transition, and an end state. This is sometimes called state mutation. Traditional imperative-style programs are often described as a series of mutations, separated with condition testing.
MoreDouble colon operator ( :: ) in Java 8 is really useful operator which may help you to reduce some code.
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