Intermediate SpringMatt Wheeler

Notes

• This is a training NOT a presentation• Please ask questions• Prerequisites

– Introduction to Java Stack– Basic Java and XML skills– Installed LdsTech IDE (or other equivalent – good luck

there ;)

Overview

• Bean lifecycle• Xml Configuration Extensions (namespace

handlers)• Lifecycle hooks

• JSR 250 • Bean post processors

• Spring Annotations• JSR 330 Annotations (@Inject, @Named)

Review

• Last time we went over– Bean definitions– Dependency Injection (DI) and Inversion of Control

(IoC)– Application context– Bean scopes

Review

<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">

<bean class="org.lds.training.SomeBean" /></beans>

ApplicationContext context = new ClassPathXmlApplicationContext("beans.xml");SomeBean someBean = context.getBean(SomeBean.class);someBean.callMethod();

• Bean definition (beans.xml)

• Application Context

Spring Bean Lifecycle

1. Create bean definitions (from xml or annotations, or, …)

2. Instantiate beans using the definitions3. Set bean dependencies (values and bean

references) on the newly instantiated beans4. Initialization5. Deliver bean to requester for use6. On container shutdown call destruction callback

method

Xml Configuration Extension

• Also called namespace handlers• Shorten bean definition configuration• Provide easily reusable definitions• Self documenting• More readable

Spring Xml Configuration Extensions

Schema Description / Documentation

util Create non-anonymous collection types that can be referenced by idhttp://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/xsd-config.html#xsd-config-body-schemas-util

jee Elements such as jndi support / ejb shortcutshttp://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/xsd-config.html#xsd-config-body-schemas-jee

lang Expose beans written in another language like JRuby or Groovyhttp://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/xsd-config.html#xsd-config-body-schemas-lang

jms Deal with configuring JMS-related beanshttp://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/xsd-config.html# xsd-config-body-schemas-jms

tx Transaction supporthttp://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/xsd-config.html# xsd-config-body-schemas-tx

Xml Configuration Extensions (cont.)

Schema Descirption / Documentation

aop Helpers for Spring’s aspect oriented programming mechanismshttp://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/xsd-config.html# xsd-config-body-schemas-aop

context Configuration relation to the application context plumbing http://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/xsd-config.html# xsd-config-body-schemas-context

tools Configuration for adding tooling specific meta-datahttp://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/xsd-config.html# xsd-config-body-schemas-tool

security Provides elements for web security configurationhttp://static.springsource.org/spring-security/site/docs/3.0.x/reference/ns-config.html

mvc Provides interceptors, view-conroller, …..http://static.springsource.org/spring/docs/3.0.x/spring-framework-reference/html/mvc.html#mvc-config

Example

• You have options

• Or

<mvc:annotation-driven validator="validator" />

<bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping"> <property name="order" value="0"/> <property name="useDefaultSuffixPattern" value="false"></property></bean>

<bean class="org.springframework.web.servlet.handler.MappedInterceptor"> <constructor-arg value="null"></constructor-arg> <constructor-arg> <bean class="org.springframework.web.servlet.handler.ConversionServiceExposingInterceptor"> <constructor-arg> <bean class="org.springframework.format.support.FormattingConversionServiceFactoryBean"></bean> </constructor-arg> </bean> </constructor-arg></bean>

Wait that’s not all

And this<bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"> <property name="webBindingInitializer"> <bean id="webBindingInitializer" class="org.springframework.web.bind.support.ConfigurableWebBindingInitializer"> <property name="validator" ref="validator" /> <property name="conversionService"> <bean class="org.springframework.format.support.FormattingConversionServiceFactoryBean" /> </property> </bean> </property> <property name="messageConverters"> <list> <bean class="org.springframework.http.converter.ByteArrayHttpMessageConverter"></bean> <bean class="org.springframework.http.converter.StringHttpMessageConverter"> <property name="writeAcceptCharset" value="false" /> </bean> <bean class="org.springframework.http.converter.ResourceHttpMessageConverter"></bean> <bean class="org.springframework.http.converter.xml.SourceHttpMessageConverter"></bean> <bean class="org.springframework.http.converter.xml.XmlAwareFormHttpMessageConverter"></bean> <bean class="org.springframework.http.converter.xml.Jaxb2RootElementHttpMessageConverter"></bean> <bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"></bean> </list> </property></bean>

Another Example• Let us utilize a namespace handler

<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:util="http://www.springframework.org/schema/util" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.0.xsd"><!-- definitions here --></beans>

 <!-- creates a java.util.List instance with the supplied values --><util:list id="alphaGroups"> <value>abc</value> <value>def</value> <value>ghi</value> <value>jkl</value></util:list>

<bean id="alphaGroups" class="org.springframework.beans.factory.config.ListFactoryBean"> <property name="sourceList"> <list> <value>abc</value> <value>def</value> <value>ghi</value> <value>jkl</value> </list> </property></bean>

Xml Configuration Extension architecture

• Pieces of namespace handlers • Create an xml schema that describes allowable

elements• Write a namespace handler• Code a BeanDefinitionParser

– Parses the defined xml and adds any necessary beans into the configuration

For Example

• Bottom line– Namespace handlers are backed by code

• The code supplements bean configuration and is a lot more than meets the eye

Add a parser example here

DEMO

Lab 3: Bean Scopes

https://tech.lds.org/wiki/Introduction_to_Spring#Lab_3_Bean_Scopes

Credit where credit is due

• http://springsource.org• Spring Recipies 2nd Edition (Gary Mak, Josh Long

and Daniel Rubio)

Dedication

• Mike Youngstrom and Bruce Campbell for their undying love and support through this process– And for reviewing and offering suggestions

• And for Spencer Uresk and Mike Heath for the inspiration

• And a special thanks to the rabbit farm who made this all possible