NOTE: The behaviors in this article are for HotSpot, other JVM might behave differently.
What is JVM? The Java Virtual Machine is the cornerstone of the Java platform. It is the component of the technology responsible for its hardware- and operating system independence, the small size of its compiled code, and its ability to protect users from malicious programs.
The Java Virtual Machine is an abstract computing machine. Like a real computing machine, it has an instruction set and manipulates various memory areas at run time. The JVM doesn’t understand Java typo, that’s why you compile your *.java files to obtain *.class files that contain the bytecodes understandable by the JVM.
Today, the Spring Framework was released to 4.2 RC2. In Spring 4.2, better application events and Server-Sent Event(SSE) are supported.
In this article, I’ll introduce you to the two new features.
What’s Server-Sent Event Server-sent events (SSE) is a technology where a browser receives automatic updates from a server via an HTTP connection. The Server-Sent Events EventSource API is standardized as part of HTML5 by the W3C.
Server-sent event is a standard describing how servers can initiate data transmission toward clients once an initial client connection has been established. They are commonly used to send message updates or continuous data streams to a browser client and are designed to enhance native, cross-browser streaming through a JavaScript API called EventSource, through which a client requests a particular URL in order to receive an event stream.
This guide walks you through the process of creating a “hello world” application that sends messages back and forth, between a browser and the server. WebSocket is a very thin, lightweight layer above TCP. It makes it very suitable to use “subprotocols” to embed messages. In this guide, we’ll dive in and use STOMP messaging with Spring to create an interactive web application.
Maven Dependencies First, we need to add the Spring messaging modules in the POM file:
Last few months, I’m working on a project with Spring MVC and Hibernate. Now, I want to try MyBatis. In this article, I’ll tell you how to useMyBatis with Spring MVC.
According to Wikipedia, database transactions should provide an “all-or-nothing” proposition, stating that each work-unit performed in a database must either be completed in its entirety or have no effect whatsoever. Further, the system must isolate each transaction from other transactions, results must conform to existing constraints in the database, and transactions that complete successfully must get written to durable storage.
A few days ago, I created TestZilla on Aliyun Elastic Compute Service.
However, with the increment of PV, I decided to use CDN to cache static files(images, CSS, and javascript).
But there’s no information on how to use CDN with Spring MVC, so I asked a question on StackOverflow.
Setup Spring Configuration First of all, you need to use PropertyPlaceholderConfigurer in Spring Configuration(such as dispatcher-servlet.xml)
<!-- Property File Location --> <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <property name="locations"> <list> <value>classpath:/testzilla.properties</value> </list> </property> </bean> <util:properties id="propertyConfigurer" location="classpath:/testzilla.properties"/> <context:property-placeholder properties-ref="propertyConfigurer" /> Of course, you need to add XML Namespaces:
A solid unit test suite is essential for ongoing development in large projects, especially those with many people involved. Going back and manually testing every individual component of an application after every change is impractical. Your unit tests will help alleviate that by automatically testing your application’s components and alerting you when something is not working the same way it was when you wrote your tests.
The Zend Framework 2 API uses PHPUnit, and so does this tutorial application. A detailed explanation of unit testing is beyond the scope of this tutorial, so we will only provide sample tests for the components in the pages that follow. This tutorial assumes that you already have PHPUnit installed.
In this article, you will learn how to create a custom view helper in Zend Framework 2. A concrete example will be used; a helper which generates links for a subdomain, intended for storing static files. This is especially useful if you wish to use a Content Delivery Network (CDN). With very little modification, the helper can be made generic to support links to subdomains for all purposes.
The Helper Class Let us begin by creating the helper class. It can be added within any module, but a suitable place would be within the Application module, provided that you made use of the Skeleton Application. Create a file CdnHelper.php in zf2-tutorial\module\Application with the following subdirectories:
This tutorial provides a sample spring MVC application that allows user sending an e-mail message.
In this tutorial, you are supposed to familiar with Java EE development as well as developing Spring MVC-based applications.
Spring Framework’s Support for E-mail Based on JavaMail, Spring framework provides high-level abstraction API which greatly simplifies e-mail sending process. Let’s take a brief look at this API in the following class diagram:
To send e-mail messages, we can use an implementation of interface MailSender – the JavaMailSenderImpl class which is built upon on JavaMail. It’s convenient to configure this implementation as a bean in Spring’s context: