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org.springframework.a op.framework.AopConfigException: Could not generate CGLIB subclass of class [class net.sf.ehcache.CacheManager]

While using Ehcache with spring, spring context initialization fails with the below exception

Caused by: org.springframework.beans.factory.BeanCreationException: Error creati
ng bean with name 'com.googlecode.ehcache.annotations.impl.CacheAttributeSourceI
mpl#0': Cannot resolve reference to bean 'ehcacheManager' while setting bean pro
perty 'cacheManager'; nested exception is org.springframework.beans.factory.Bean
CreationException: Error creating bean with name 'ehcacheManager': Post-processi
ng of the FactoryBean's object failed; nested exception is org.springframework.a
op.framework.AopConfigException: Could not generate CGLIB subclass of class [cla
ss net.sf.ehcache.CacheManager]: Common causes of this problem include using a f
inal class or a non-visible class; nested exception is org.springframework.cglib
.core.CodeGenerationException: net.sf.ehcache.CacheException-->Another unnamed C
acheManager already exists in the same VM. Please provide unique names for each
CacheManager in the config or do one of following:
1. Use one of the CacheManager.create() static factory methods to reuse same Cac
heManager with same name or create one if necessary
2. Shutdown the earlier cacheManager before creating new one with same name.
The source of the existing CacheManager is: InputStreamConfigurationSource [stre
am=java.io.BufferedInputStream@128647a]

Configuration Details:

<?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:ehcache="http://ehcache-spring-annotations.googlecode.com/svn/schema/ehcache-spring"
     xsi:schemaLocation="
     http://www.springframework.org/schema/beans
     http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
     http://ehcache-spring-annotations.googlecode.com/svn/schema/ehcache-spring
     http://ehcache-spring-annotations.googlecode.com/svn/schema/ehcache-spring/ehcache-spring-1.1.xsd">

<ehcache:annotation-driven cache-manager="cacheManager"/>

<bean id="cacheManager" class="org.springframework.cache.ehcache.EhCacheManagerFactoryBean">
  <property name="configLocation" value="classpath:config/ehcache/ehcache.xml" />
  <property name="shared" value="true" />
</bean>
</beans>

Unit Testing the Velocity Templates in spring

It is painful to test the Velocity Template  by deploying to the server while doing frequent changes.
The unit testing  will help as to overcome this and do proper testing without deploying the project to the server.
This post will explain the approach to unit test the Velocity Templates through eclipse.

Spring velocity configurations

Create a Velocity-test.xml configuration file to configure the velocity bean - instead of creating separate configuration file we can also use the project configuration file that has the velocity bean configuration (e.g. application-context.xml)


Change the vm template path accordingly.

Create a test java class (VelocityTest.java)

import java.io.*;
import java.util.ArrayList;
import org.apache.velocity.app.VelocityEngine;
import org.apache.velocity.context.*;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.thomson.ecom.core.velocity.VelocityContextBuilder;
public class VelocityTest
{
public static void main(String[] args) throws Exception
{
ApplicationContext ctx = new ClassPathXmlApplicationContext("classpath:velocity-test.xml");
ArrayList<Employee> employeeList=new ArrayList<Employee>();

Employee emp1=new Employee();
emp1.setContactNo("111111");
emp1.setDept("CSC");
emp1.setEmail("[email protected]");
emp1.setEmpName("Albin");
emp1.setEmpNo("1");
emp1.setLocation("Bangalore");
employeeList.add(emp1);

Employee emp2=new Employee();
emp2.setContactNo("22222");
emp2.setDept("IT");
emp2.setEmail("[email protected]");
emp2.setEmpName("Albin1");
emp2.setEmpNo("2");
emp2.setLocation("Bangalore");
employeeList.add(emp2);

Employee emp3=new Employee();
emp3.setContactNo("33333");
emp3.setDept("IT");
emp3.setEmail("[email protected]");
emp3.setEmpName("Albin2");
emp3.setEmpNo("3");
emp3.setLocation("Bangalore");
employeeList.add(emp3);

VelocityEngine engine = ctx.getBean("velocityEngine", VelocityEngine.class);
Context velocityCtx = VelocityContextBuilder.getInstance().buildContext();
velocityCtx.put("empList", employeeList);

Writer w = new FileWriter(new File("D:\\Albin\\velocity.html"));
engine.mergeTemplate("EmployeeEmailTemplate.vm", velocityCtx, w);
w.close();

System.exit(0);
}
}

Change the velocity.html file path and the vm template name accordingly.
Pass the required inputs to the velocityCtx map.
Execute the VelocityTest.java; this will generate the velocity.html file in the specified location.

Resolving cvc-elt.1: Cannot find the declaration of element 'beans' in Spring

I was receiving the following exception while running the Spring application in standalone mode with maven and eclipse.

Exception in thread "main" org.springframework.beans.factory.xml.XmlBeanDefinitionStoreException: Line 11 in XML document from class path resource [encrypt/encrypting-test.xml] is invalid; nested exception is org.xml.sax.SAXParseException: cvc-elt.1: Cannot find the declaration of element 'beans'.
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:396)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:334)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:302)
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:143)

Caused by: org.xml.sax.SAXParseException: cvc-elt.1: Cannot find the declaration of element 'beans'.
at org.apache.xerces.util.ErrorHandlerWrapper.createSAXParseException(Unknown Source)
at org.apache.xerces.util.ErrorHandlerWrapper.error(Unknown Source)

Unfortunately, I could not able to find any issue in my bean configuration file.

<? 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:jee="http://www.springframework.org/schema/jee" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd">

    <bean id="encryptXMLPayload" class="com.encrypt.EncryptXMLPayload">

          <property name="encryptor" ref="encryptor" /> 

          <property name="messageStylesheet" value="classpath:encrypt/encryptXMLPayload.xslt" />

     </bean>

     <bean id="encryptor" class="com.encrypt.Encryptor" init-method="init">

           <property name="keyData" value="pYOkcj4_kf-4hn-A-IkclLWDBJI-T5bd"/>

     </bean> 

 </beans>

After analysis, the issue is with version mismatch between the pom.xml(spring version configured) and the schema version  configured in the bean configuration file

<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>3.0.0.RELEASE</version>
<scope>compile</scope>
</dependency>

<? 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:jee="http://www.springframework.org/schema/jee" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd">

How to Fix

The issue got resolved after changing the schema version to 3.0 in the bean configuration file as shown below

<? 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:jee="http://www.springframework.org/schema/jee" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd"> 

The spring version configured in the pom.xml and the schema version used in the bean configuration files should be matching.

Loading configuration properties from Database Table in Spring Application

This is better approach to store the configuration properties to a database table so that this can be managed easily.
This post will explains the approach to store and retrieve the configuration properties from database table in spring project.

Bean definition in Spring context file:

Configure the below bean definition to the spring context file

<!--  Loads properties to set environment-specific values within the DB table for that environment -->
<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="systemPropertiesModeName" value="SYSTEM_PROPERTIES_MODE_OVERRIDE" />
<property name="properties">
<bean class="org.apache.commons.configuration.ConfigurationConverter"
factory-method="getProperties">
<constructor-arg>
<bean class="org.apache.commons.configuration.DatabaseConfiguration">
  <constructor-arg>
  <ref bean="propertyDataSource"/>
</constructor-arg>
     <constructor-arg value="Properties"/>  <!--  DB Table -->
     <constructor-arg value="prop_key"/> <!-- DB Key Column -->
   <constructor-arg value="prop_value"/> <!--  DB Value Column -->
   </bean>
</constructor-arg>
</bean>
</property>
</bean>

Properties database table

The Properties database table should be pre-created with the required configuration values

Prop_key	Prop_value
ftp.host	localhost
ftp.user	albin

Testing the Spring Service layer through JUnit

Steps to enable Junit test for spring service layer

This post will explains the steps required to test the spring service layer through JUnit without deploying to the server.

Right Click on the service class for which the test class needs to be created and click on New and select JUnit Test Case


Click on Next and provide the Test Class Name and the package to which the test class has to be created.


Click on Next and select the methods for which the test methods needs to be created and click on finish.

Getting the logged-in user details in Spring

The below piece of code will help us to get the logged-in user details from spring security context.

User user = (User)SecurityContextHolder.getContext().getAuthentication().getPrincipal();
       
Sting userName=user.getUsername();