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Some of my learning notes about using the excellent Spring MVC framework to build a simple MVC based web application. Spring MVC is an action oriented framework. For a good overview on the differences between UI Component and Action oriented frameworks checkout this link. In action oriented MVC land, the controller dispatches to a specific action, based on information in the request. Each action does a specific thing to transform the request and take action on it, possibly updating the model tier. This approach does not try to hide the request/response model of the underlying HTTP, and it also says absolutely nothing about the specifics of the HTML/CSS/JS comprising the UI. ...

Maven dependencies: <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.21</version> </dependency> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-entitymanager</artifactId> <version>4.1.9.Final</version> </dependency> <dependency> <groupId>javax.transaction</groupId> <artifactId>jta</artifactId> <version>1.1</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> <version>3.2.0.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-orm</artifactId> <version>3.2.0.RELEASE</version> </dependency> Entity Manager Factory Used to bootstrap JPA and also Hibernate inside our application. The LocalContainerEntityManagerFactoryBean which is packaged in the spring-orm.jar, references the defined persistence unit. <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"> <property name="persistenceUnitName" value="punit" /> <property name="dataSource" ref="dataSource" /> <property name="jpaVendorAdapter"> <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"> <property name="showSql" value="true" /> </bean> </property> <property name="jpaPropertyMap"> <map> <entry key="hibernate.dialect" value="org.hibernate.dialect.MySQL5InnoDBDialect" /> <entry key="hibernate.hbm2ddl.auto" value="none" /> <entry key="hibernate.format_sql" value="true" /> </map> </property> </bean> Transaction Manager The JpaTransactionManager (packaged within spring-tx.jar) which sucks in a reference to the entityManagerFactory, is responsible for taking care of transactions within the JPA layer. ...

Occassionally the need to do multiple side-by-side deployments of the same packaged application can arise. In a scenario recently faced, it was useful to have multiple versions of our packaged EAR deployed and configured slightly differently (for example: with and without security in QA environments). As the application is expected to run hot 24/7, the need for a simple side-by-side versioning (e.g. v1, v2) scheme was also important. Allowing us to deploy v1, and later breaking (incompatible) versions v2, v3, given our service consumers the freedom to upgrade when convenient. ...

Java EE is packed tight with useful functionality. The humble Interceptor provides cross cutting functionality external to the targetted code, without modifying the code itself. In other words AOP. The API is rather simple an involves using @AroundInvoke. The following highlights just how simple it is to log all EJB service call execution times, without the need to modify a single bean. META-INF/ejb-jar.xml <?xml version="1.0" encoding="UTF-8"?> <ejb-jar xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/ejb-jar_3_1.xsd" version="3.1"> <display-name>SerivceModuleEJB</display-name> <assembly-descriptor> <interceptor-binding> <ejb-name>*</ejb-name> <interceptor-class> net.bencode.common.ServicePerformanceInterceptor </interceptor-class> </interceptor-binding> </assembly-descriptor> </ejb-jar> ServicePerformanceInterceptor.java ...

Amped by @yaamehn’s opinionated Microservices A Reference Architecture recent talk at the Microservices Australia Meetup, has got me thinking about the many interesting possibilities Microservices stirs up. Many useful techniques are touched on, regardless of whether actually adopting Microservices. On the surface Microservices doesn’t appear to be anything groundbreakingly new. It does however push tried-and-trued concepts (e.g. abstraction, decoupling, modularisation, continuous delivery) to extreme levels. Fused with innovations in the operations space such as containerising like Docker, can lead to some very powerful outcomes; such efficient continuous delivery (on a micro scale), decoupling of domains allowing for a best of bread technlogies, and so on. ...

One of the best ways to evolve in the software industry is to interact with other developers and those technically minded. Resources such as user groups, Twitter and conferences are useful for this. It’s disturbingly easy to develop reality distortion or tunnel vision with the projects and technology stacks you spend a majority of your time with. Conferences on my radar: January linux.conf.au, Geelong Febuary APIdays, Sydney ...

Well first time for everything. Messing around with some JAX-WS web services, wanted to spin up my favourite SOAP frontend, soapUI. On my Mac. Annoyingly it would just immediately hang. Completely frozen. soapUI by default will try and render a web page on startup. This doesn’t seem to work out so well when running on OSX. A handy little article I found on Anton Perez’s blog, made my day. Start ‘Activity Monitor’ and Force Kill your dead soapUI process. In Finder, /Applications/SmartBear/soapUI-5.0.0.app > Show Package Contents. Edit /Applications/SmartBear/soapUI-5.0.0.app/Contents/java/app/bin/soapui.sh. Uncomment this line# JAVA_OPTS="$JAVA_OPTS -Dsoapui.browser.disabled=true". Edit /Applications/SmartBear/soapUI-5.0.0.app/Contents/vmoptions.txt. Add -Dsoapui.browser.disabled=true. Start soapUI. Checkout these commented lines in soapui.sh…our fix ready to go: ...

Lately I’ve gleened some “real world” Apache Ant tips and tricks from some really impressive Java EE developers I’ve had the opportunity of working with over the last year. Apache Ant is a Java library and command-line tool whose mission is to drive processes described in build files as targets and extension points dependent upon each other. Ant supplies a number of built-in tasks allowing to compile, assemble, test and run Java applications. ...

So I’ve been using WebSphere for a while now, and continue to discover new functionality in this powerhouse of an application server. This post focuses on performing background work in WebSphere Application Server (WAS) 7.0, which is an EE 5 compliant container. Firstly a quick outline of the problem. Across a series of web service calls, there exist a number of intensive processes that need to take place. I wanted a way to perform work this asynchronously somewhere else within the application server, without being bound to the request/response cycle that HTTP web services impose…in essence making the actual service calls appear super snappy. ...

BCAA’s (Branched chain amino acids) have always had a place in my gym bag for about the last 2 years. A branched-chain amino acid (BCAA) is an amino acid having aliphatic side-chains with a branch (a carbon atom bound to more than two other carbon atoms). Among the proteinogenic amino acids, there are three BCAAs: leucine, isoleucine and valine. The BCAAs are among the nine essential amino acids for humans, accounting for 35% of the essential amino acids in muscle proteins and 40% of the preformed amino acids required by mammals ...