Spring Tutorials

Spring Tutorial

Introduction of Spring Framework

Advantages and Disadvantages of Spring Framework

Features of Spring Framework

Basic concept of Spring Framework

Architecture of Spring Framework

Modules of Spring Framework

Goal of Spring Framework

Create Application of Spring without any IDE

Create Application of Spring in Eclipse IDE

Create Application of Spring in MYEclipse IDE

Important JAR of Spring Framework

IOC container in Spring Framework

Bean and Applicationcontext container in Spring Framework

Example of Spring BeanFactory Container in Spring Framework

Example of Spring ApplicationContext Container in Spring Framework

Bean in Spring Framework

Lifecycle of Bean in Spring Framework

Scope of Bean in Spring Framework

Autowiring in Spring Framework

Dependency Injection in Spring Framework

Constructor-based Dependency Injection Example in Spring Framework

Setter-based Dependency Injection Example in Spring Framework

Introduction of AOP in Spring Framework

Core concept and Goal of AOP in Spring Framework

AOP Proxies in Spring framework

XML Schema Based AOP in Spring Framework

AOP Xml based Configuration Example in Spring Framework

Example of Declaring AOP Advices in Spring Framework

AOP AspectJ Annotation with Example in Spring Framework

Declaring an aspect and pointcut using Annotation in Spring Framework

Declaring AOP Advices using Annotation Example in Spring Framework

DAO support in Spring Framework

Introduction of Spring JDBC Framework in Spring Framework

Introduction of Spring JdbcTemplate in Spring Framework

Example of Spring JdbcTemplate class in Spring framework

Example of Executing SQL statements in Spring Framework

Example of Executing DDL statements in Spring Framework

SQL Stored Procedure in Spring Framework

Example of NamedParameterJdbcTemplate in Spring Framework

Example of RowMapperJdbcTemplate in Spring Framework

Introduction of ORM Framework in Spring Framework

Integration of Spring with Hibernate in Spring Framework

Integration of Spring with JPA in Spring Framework

Introduction of Spring Expression Language (SpEL) in Spring Framework

Example of Spring Expression Language (SpEL) in Spring framework

Example of Spring EL in XML and Annotation in Spring Framework

Language Reference with SpEL in Spring Framework

Operators in Spring Expression Language(SpEL) in Spring Framework

Variable in Spring Expression Language(SpEL) in Spring Framework

Introduction of Spring Framework Transaction Management in Spring Framework

Spring Framework Transaction Abstraction

Spring Declarative Transaction Management in Spring Framework

Spring Programmatic Transaction Management in Spring Framework

Introduction of Spring OXM (Object XML Mapping) in Spring Framework

Integration of Spring with Jaxb Example in Spring framework

Example of Spring with Xstream in Spring Framework

Example of Spring with Castor in Spring Framework

Remote Method Invocation(RMI) in Spring Framework

Spring and RMI Integration with Example in Spring Framework

Example of Spring and Httpinvoker in Spring Framework

Example of Spring and Hessian in Spring Framework

Integration of Spring with JMS in Spring Framework

Introduction of Webservice in Spring Framework

Spring Web Services in Spring Framework

Web Services with Jax-WS in Spring framework

Exposing and Exporting servlet-based Web Services using JAX-WS in Spring Framework

Accessing Web Services using JAX-WS in Spring Framework

Introduction of JMS in Spring Framework

JMS Messaging Models in Spring Framework

Using Spring JMS in Spring Framework

Sending and Receiving a Message Using JMS API in Spring Framework

Introduction of JMX (Java Management Extension) in Spring Framework

Integrating Beans with JMX in Spring Framework

Creating a MBeanServer in Spring Framework

Introduction Java Mail with Spring in Spring Framework

Example of Java Mail with spring in Spring Framework

Introduction of EJB(Enterprise JavaBeans) in Spring Framework

Introduction of EJB(Enterprise JavaBeans) Integration in Spring Framework

Integration of Spring With Struts 2 Example in Spring Framework

Spring MVC

Spring MVC

Introduction of EJB(Enterprise JavaBeans) Integration
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Enterprise Java Beans (EJB) can be used extensively in Springís environment. The transparent support available in Spring for using the Stateless and the Stateful Session Beans in Spring.As a lightweight container, Spring is often considered an EJB replacement.

We do believe that for many if not most applications and use cases, Spring as a container, combined with its rich supporting functionality in the area of transactions, ORM and JDBC access, is a better choice than implementing equivalent functionality via an EJB container and EJBs.

It is important to note that using Spring does not prevent you from using EJBs. Spring makes it much easier to access EJBs and implement EJBs and functionality within them. Additionally, using Spring to access services provided by EJBs allows the implementation of those services to later transparently be switched between local EJB, remote EJB, or POJO (plain old Java object) variants, without the client code having to be changed.

API Support for EJB in Spring

The Spring Distribution for providing integration support of Enterprise Beans.That provide the important classes available in the following packages:

  • org.springframework.ejb.support
  • org.springframework.ejb.access
Accessing EJBs(Enterprise Java Beans)

There are two ways to accessing EJB in Spring. When call a method on a local or remote stateless session bean, client code must normally perform a JNDI lookup to obtain the (local or remote) EJB Home object, then use a create method call on that object to obtain the actual (local or remote) EJB object. One or more methods are then invoked on the EJB.

To avoid repeated low-level code, many EJB applications use the Service Locator and Business Delegate patterns. These are better than spraying JNDI lookups throughout client code, but their usual implementations have significant disadvantages.

For example

  1. Typically code using EJBs depends on Service Locator or Business Delegate singletons, making it hard to test.
  2. In the case of the Service Locator pattern used without a Business Delegate, application code still ends up having to invoke the create() method on an EJB home, and deal with the resulting exceptions. Thus it remains tied to the EJB API and the complexity of the EJB programming model.
  3. Implementing the Business Delegate pattern typically results in significant code duplication, where we have to write numerous methods that simply call the same method on the EJB.

The Spring approach is to allow the creation and use of proxy objects, normally configured inside a Spring container, which act as codeless business delegates.

 

Accessing Local SLSBs(Stateless Session Bean)

Spring Framework especially supports accessing stateless type of EJB. The obtained EJB is here treated like an ordinary Spring bean (type: org.springframework.ejb.access.LocalStatelessSessionProxyFactoryBean). There needs to be specified the JNDI name of the EJB and the business interface in Spring bean definition. Additionally, when the resourceRef attribute is set to true then the mandatory JNDI prefix: java:comp/env is added automatically to the name.

<bean id="eJBService"
class="org.springframework.ejb.access.LocalStatelessSessionProxyFactoryBean">
<property name="jndiName" value="ejb/eJBService"/>
<property name="businessInterface" value="com.r4r.in.eJBService"/>
<property name="resourceRef" value="true" />
</bean>
<bean id="springController" class="com.r4r.springController">
<property name="ejbService" ref="eJBService" />
</bean>

The springController bean definition sets the eJBService property of the controller class to the EJB proxy. Alternatively (and preferably in case of many such proxy definitions), consider using the <jee:local-slsb> configuration element in Springís "jee" namespace:

<jee:local-slsb id="eJBService"
business-interface="com.r4r.ejbService"
jndi-name="ejb/eJBService" resource-ref="true" />

This EJB access mechanism delivers huge simplification of application code: the web tier code has no dependence on the use of EJB. If we want to replace this EJB reference with a POJO or a mock object or other test stub, we could simply change the eJBService bean definition without changing a line of Java code. Additionally, we havenít had to write a single line of JNDI lookup or other EJB plumbing code as part of our application.

Accessing remote SLSBs(Stateless Session Bean)

Accessing remote EJBs is essentially identical to accessing local EJBs, except that the SimpleRemoteStatelessSessionProxyFactoryBean or <jee:remote-slsb> configuration element is used. of course, with or without Spring, remote invocation semantics apply; a call to a method on an object in another VM in another computer does sometimes have to be treated differently in terms of usage scenarios and failure handling.

There is also possible to obtain remote EJB component by using SimpleRemoteStatelessSessionProxyFactoryBean instead of LocalStatelessSessionProxyFactoryBean and remote-slsb instead of local-slsb in case of spring-jee.xsd schema. The JndiEnvironment probably will be required to specify to access remote objects.

  1. Prepare EJB component
  2. Define an appropriate Spring bean representing EJB (point to right JNDI name, business interface, optionally set additional properties e.g. resourceRef) by specifying FactoryBean class:
  3. org.springframework.ejb.access.LocalStatelessSessionProxyFactoryBean or

    org.springframework.ejb.access.SimpleRemoteStatelessSessionProxyFactoryBean.

  4. Use the bean definition where needed.
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