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Authentication Mechanisms for Web Applications


Authentication is the basic requirement for most of websites. However, there are many mechanisms to implement authentication and they are not very interchangeable. Depend on business requirement, developers need to choose the most appropriate method of authentication for their application. It may not be an easy task unless one understand the differences among mechanisms well. In this short article, I ...

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9 Docker recipes for Java EE Application


Cross-posted from So, you’d like to start using Docker for Java EE applications? A typical Java EE application consists of an application server, such as WildFly, and a database, such as MySQL. In addition, you might have a separate front-end tier, say Apache, for load balancing a number of application server. A caching layer, such as Infinispan, may be used ...

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69 个Spring 面试问题和答案 – 终极列表 (PDF 下载)


这篇文章是关于Spring框架的一些最重要问题的总结,在面试或笔试过程中可能被问到! 不用担心您的下一个面试的的测试,因为Java Code Geeks会为您服务!您可能被问到的大部分问题都列在了这里。所有的核心模块, 从基础的Spring功能例如Spring Beans到 Spring MVC 框架都被列在了这里而且简单的介绍了。在查看了这些面试问题后,您可以查看我们的 Spring教程页面。那么,我们开始吧…!   提示:您在寻找java方面的工作机会吗?访问我们的工作面板  来搜索和查看精心选择的为全世界的IT专业人士准备的Java工作。另外,您也可以把您的简历添加到我们的  简历面板来提高您的技能来使全世界的Java招聘者看到您。 目录 Spring 概述 依赖注入 Spring Beans Spring 注解 Spring 数据访问 Spring 面向方面编程 (AOP) Spring 模型视图控制器 (MVC) Spring 概述 1. Spring是什么? Spring是针对企业版 Java的开源的开发框架 。Spring框架的核心功能能被用于开发任何的Java程序,但有针对基于Java EE平台上的Web应用程序的扩展。Spring框架的目标是使JavaEE的开发更加容易并通过使用基于POJO的编程模型来促进编程最佳实践的应用。 2. Spring 框架有什么优势? 轻量级: 在尺寸和透明度方面Spring 是轻量级的。spring框架的基础版本只有大约 2MB 大小。 控制反转 (IOC): 通过控制反转技术 ,Spring实现了松耦合。对象间只是给出了依赖性,而不是创建或寻找依赖对象。 面向切面 (AOP): Spring 支持面向切面编程 而且把应用的业务逻辑从系统服务分离开了。 容器: Spring 包含并管理应用对象的生命周期和配置。 MVC 框架: Spring的 web 框架是一个设计良好的 web MVC 框架, 它可以作为其他web框架的替代。 事务管理: ...

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Improving performance: non-blocking processing of streams


1. Introduction Imagine we have an application that needs to access an external web service in order to gather information about clients and then process it. More specifically, we can’t get all this information in a single invocation. If we want to look up different clients, we will need several invocations. As shown in the graphic below, the example application ...

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Microservices, DevOps, and the cost of change?


As developers, we all love shiny new things. New technologies (Docker, Kubernetes), new languages (Golang, NodeJS), new hyped conversation starters (Microservices, DevOps, Cloud). And everyone seems to have an opinion about why you should do this architecture, or why you should use that language. At the end of the day, your employer is expecting you to deliver using a means ...

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Turning on GC logging at runtime


There is always the next JVM behaving badly. And you know by heart that if you just could have had those few startup options exposing some more information about what is going on, you might have stood a chance of actually fixing the goddamn thing. But nope, exactly the flag you need (be it -XX:+HeapDumpOnOutOfMemoryError or -XX:+PrintGCDetails) is always missing. ...

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Getting Java Event Notification Right


Implementing the observer pattern to provide Java event notification seems to be a straight forward thing to do. However there are some pitfalls one easily can run into. Here comes an explanation of common mistakes I carelessly have produced myself on various occasions… Java Event Notification Let’s start with a simple bean StateHolder that encapsulates a private int field state ...

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Spring Boot Integration Testing with Selenium


Web integration tests allow integration testing of Spring Boot application without any mocking. By using @WebIntegrationTest and @SpringApplicationConfiguration we can create tests that loads the application and listen on normal ports. This small addition to Spring Boot makes much easier to create integration tests with Selenium WebDriver. Test Dependencies The application that we will be testing is a simple Spring ...

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Nifty JUnit : Using Rule on Method and Class level


As shown in a the post Nifty JUnit : Working with temporary files, it is possible to use @Rule in a JUnit test, which is a Method level Rule. In this example I would like to show the variation of the @ClassRule for a Class level Rule. Method Rule The @Rule is fired before each test method (just like @Before) ...

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Hibernate CascadeType.LOCK gotchas


Introduction Having introduced Hibernate explicit locking support, as well as Cascade Types, it’s time to analyze the CascadeType.LOCK behavior. A Hibernate lock request triggers an internal LockEvent. The associated DefaultLockEventListener may cascade the lock request to the locking entity children. Since CascadeType.ALL includes CascadeType.LOCK too, it’s worth understanding when a lock request propagates from a Parent to a Child entity. ...

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