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Spring Classpath Scan Breaks When Migrating From JBoss4 to JBoss5

04.09.2010
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Spring 2.5 classpath scan does not work on JBoss5 due to internal architecture changes in JBoss5. You may face this issue when migrating from JBoss4 to JBoss5. This article walks you through a simple fix, with code snippets.

Classpath scan issue

In JBoss 4, your application was probably using Spring 2.5.6 with classpath scan to load spring beans (as shown below). When migrating your code to JBoss5, you will notice that component-scan does not work with JBoss5. Symptoms may include null Spring components or if you were using Spring Seam integration and the Spring beans were loaded through classpath scan then you may be the following error:

Seam Code

public class LoginController extends Controller {
@In("#{userService}")
protected demo.entity.service.UserService userService;
public class LoginController extends Controller {
    @In("#{userService}")
    protected demo.entity.service.UserService userService;

Stacktrace

Caused by: org.jboss.seam.RequiredException: @In attribute requires non-null value: loginController.#{userService}
at org.jboss.seam.Component.getValueToInject(Component.java:2335)
at org.jboss.seam.Component.injectAttributes(Component.java:1736)
at org.jboss.seam.Component.inject(Component.java:1554)
at org.jboss.seam.core.BijectionInterceptor.aroundInvoke(BijectionInterceptor.java:61)
at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68)
Caused by: org.jboss.seam.RequiredException: @In attribute requires non-null value: loginController.#{userService}
 at org.jboss.seam.Component.getValueToInject(Component.java:2335)
 at org.jboss.seam.Component.injectAttributes(Component.java:1736)
 at org.jboss.seam.Component.inject(Component.java:1554)
 at org.jboss.seam.core.BijectionInterceptor.aroundInvoke(BijectionInterceptor.java:61)
 at org.jboss.seam.intercept.SeamInvocationContext.proceed(SeamInvocationContext.java:68)

Spring 2.5.6 dependency in pom.xml

 <dependency>
<groupId>org.springframework</groupId>
<artifactId>spring</artifactId>
<version>2.5.6</version>
</dependency>
 <dependency>
 <groupId>org.springframework</groupId>
 <artifactId>spring</artifactId>
 <version>2.5.6</version>
 </dependency

Old spring config XML

<?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:context="http://www.springframework.org/schema/context"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans

http://www.springframework.org/schema/beans/spring-beans-2.5.xsd

http://www.springframework.org/schema/tx

http://www.springframework.org/schema/tx/spring-tx-2.5.xsd

http://www.springframework.org/schema/context

http://www.springframework.org/schema/context/spring-context-2.5.xsd"
default-init-method="init" default-destroy-method="shutdown">
<context:annotation-config />
<context:component-scan base-package="demo.dao.jpa" />
</beans>
<?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:context="http://www.springframework.org/schema/context"
 xmlns:tx="http://www.springframework.org/schema/tx"
 xsi:schemaLocation="http://www.springframework.org/schema/beans

http://www.springframework.org/schema/beans/spring-beans-2.5.xsd

http://www.springframework.org/schema/tx

http://www.springframework.org/schema/tx/spring-tx-2.5.xsd

http://www.springframework.org/schema/context

 http://www.springframework.org/schema/context/spring-context-2.5.xsd"
 default-init-method="init" default-destroy-method="shutdown">
 <context:annotation-config />
 <context:component-scan base-package="demo.dao.jpa" />
</beans>

If you run the above code in JBoss5, component-scan does not work. See this JIRA issue on Spring’s website.

Solution

You need to migrate your spring version from 2.5.6 to 3.0.0.RELEASE. Remove your old spring dependency for 2.5.6 and add the following. Add snippets for the components that your application needs. Here’s a list of common spring components and their maven dependencies.

New dependency

 <dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-orm</artifactId>
<version>3.0.0.RELEASE</version>
</dependency>

<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>3.0.0.RELEASE</version>
</dependency>

<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>3.0.0.RELEASE</version>
</dependency>
 <dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>3.0.0.RELEASE</version>
<scope>test</scope>
</dependency>
 <dependency>
 <groupId>org.springframework</groupId>
 <artifactId>spring-test</artifactId>
 <version>3.0.0.RELEASE</version>
 <scope>test</scope>
 </dependency>

Complete list is available here. After making this change, build your project with the new dependencies. Your old code should work with Spring 3 on JBoss 5.1.0.GA.

From http://www.vineetmanohar.com/2010/04/08/spring-classpath-scan-issue-jboss5

Published at DZone with permission of Vineet Manohar, author and DZone MVB.

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Comments

Samir Sanghvi replied on Fri, 2011/04/15 - 6:06pm

Thaks for your explanation..

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