Context initialization failing due to inner class usage

[j.gohel]

Hello,

I have a bean which i want to validate using my Validator implementation.
This Validator implementation i have declared as inner class.
But a context initialization failed exception is occuring with the details as follows:

Caused by: org.springframework.beans.factory.BeanCreationException: Error creati
ng bean with name 'customerFormValidator' defined in ServletContext resource [/W
EB-INF/app-servlet.xml]: Instantiation of bean failed; nested exception is org
.springframework.beans.BeanInstantiationException: Could not instantiate bean cl
ass [com.models.CustomerBean$CustomerBeanValidator]: No default constructo
r found; nested exception is java.lang.NoSuchMethodException: com.models.C
ustomerBean$CustomerBeanValidator.<init>()
Caused by: org.springframework.beans.BeanInstantiationException: Could not insta
ntiate bean class [com.models.CustomerBean$CustomerBeanValidator]: No defa
ult constructor found; nested exception is java.lang.NoSuchMethodException: com.
models.CustomerBean$CustomerBeanValidator.<init>()
Caused by: java.lang.NoSuchMethodException: com.models.CustomerBean$Custom
erBeanValidator.<init>()
        at java.lang.Class.getConstructor0(Class.java:2647)
        at java.lang.Class.getDeclaredConstructor(Class.java:1953)
        at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:6
0)
        at org.springframework.beans.factory.support.SimpleInstantiationStrategy
.instantiate(SimpleInstantiationStrategy.java:45)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBean
Factory.instantiateBean(AbstractAutowireCapableBeanFactory.java:701)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBean
Factory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:687)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBean
Factory.createBean(AbstractAutowireCapableBeanFactory.java:388)
        at org.springframework.beans.factory.support.AbstractBeanFactory$1.getOb
ject(AbstractBeanFactory.java:250)
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistr
y.getSingleton(DefaultSingletonBeanRegistry.java:141)
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean
(AbstractBeanFactory.java:247)
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean
(AbstractBeanFactory.java:161)
        at org.springframework.beans.factory.support.BeanDefinitionValueResolver
.resolveReference(BeanDefinitionValueResolver.java:245)
        at org.springframework.beans.factory.support.BeanDefinitionValueResolver
.resolveValueIfNecessary(BeanDefinitionValueResolver.java:124)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBean
Factory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1019)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBean
Factory.populateBean(AbstractAutowireCapableBeanFactory.java:809)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBean
Factory.createBean(AbstractAutowireCapableBeanFactory.java:425)
        at org.springframework.beans.factory.support.AbstractBeanFactory$1.getOb
ject(AbstractBeanFactory.java:250)
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistr
y.getSingleton(DefaultSingletonBeanRegistry.java:141)
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean
(AbstractBeanFactory.java:247)
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean
(AbstractBeanFactory.java:161)
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.
preInstantiateSingletons(DefaultListableBeanFactory.java:273)
        at org.springframework.context.support.AbstractApplicationContext.refres
h(AbstractApplicationContext.java:346)
        at org.springframework.web.context.support.AbstractRefreshableWebApplica
tionContext.refresh(AbstractRefreshableWebApplicationContext.java:156)
        at org.springframework.web.servlet.FrameworkServlet.createWebApplication
Context(FrameworkServlet.java:308)
        at org.springframework.web.servlet.FrameworkServlet.initWebApplicationCo
ntext(FrameworkServlet.java:252)
        at org.springframework.web.servlet.FrameworkServlet.initServletBean(Fram
eworkServlet.java:221)
        at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.
java:115)
        at javax.servlet.GenericServlet.init(GenericServlet.java:212)

The code snippet from my app-servlet.xml is as follows :

<bean id="customerFormController"
                 class="com.controllers.CustomerFormController">
                 <property name="formView">
                        <value>client.htm</value>
                 </property>
                 <property name="successView">
                        <value>client.htm</value>
                 </property>
                  <property name="commandName" value="customerBean" />
                  <property name="commandClass">
                        <ref bean="customerBean" />
                  </property>
                  <property name="validator">
                        <ref bean="customerFormValidator" />
                  </property>
                  <property name="validateOnBinding">
                        <value>true</value>
                  </property>

                  <property name="pageCaption">
                        <value>Clients</value>
                  </property>
        </bean>
        
        <bean id="customerBean" class="com.models.CustomerBean" />
        <bean id="customerFormValidator" class="com.models.CustomerBean$CustomerBeanValidator" />

My bean code snippet is as follows:

public class CustomerBean 
{
    private String customerName;
    private String companyName;

    public void setCustomerName(String customerName) {
          this.customerName = customerName;
    }

    public String getCustomerName() {
        return customerName;
    }

    public void setCompanyName(String companyName) {
        this.companyName = companyName;
    }

    public String getCompanyName() {
        return companyName;
    }

   /**
     *  Validates the customer's details submitted.
     *
     */
    protected class CustomerBeanValidator implements Validator {

            public CustomerBeanValidator() {
            }
            /**
             * Returns true if this validator can validate instances of supplied clazz,
             * else false.
             *
             *@param clazz : the class that this Validator is being asked to validate
             */
            public boolean supports(Class clazz) {
                return CustomerBean.class.isAssignableFrom(clazz);
            }

            /**
             * Validates the supplied "target" object, which must be of a Class for which the 
             * supports(Class) method typically has(or would) return true.
             * The supplied "errors" instance can be used to report ant resulting validation errors.
             *
             * @param target : the object that is to be validated(can be "null")
             * @param errors : contextual state about the  validation process(never "null")
             */
            public void validate(Object target, Errors errors) {
                    ValidationUtils.rejectIfEmptyOrWhitespace(errors,"customerName","required","Field is required");
                    ValidationUtils.rejectIfEmptyOrWhitespace(errors,"companyName","required","Field is required");
            }
    }
}

Can anybody please let me know where i have gone wrong??

Thanks.

[lumpynose]

It's giving the error "No default constructor found". I'm guessing that's because your inner class is protected and not public. Just put it in a separate file and make it public. You're working with java and spring; just get used to having billions of files.

[j.gohel]

Hi lumpynose,
Thanks for the reply.

As per your suggestion of making a separate java file for my validator implemenation, i had already implemented the code that way and it is working.

But what i am trying is that the bean and its validation logic both remain together.Hence defined the Validator implementation as Inner class.

Also i tried the option of declaring the inner class's constructor as public.But the same exception was persisting as mentioned in my first post.

I debugged the application and found out that, in the following method of java.lang.Class, the exception is occuring.

private Constructor[] privateGetDeclaredConstructors(boolean publicOnly) {
        checkInitted();
        Constructor[] res = null;
        if (useCaches) {
            if (publicOnly) {
                if (publicConstructors != null) {
                    res = (Constructor[]) publicConstructors.get();
                }
            } else {
                if (declaredConstructors != null) {
                    res = (Constructor[]) declaredConstructors.get();
                }
            }
            if (res != null) return res;
        }
        // No cached value available; request value from VM
        if (isInterface()) {
            res = new Constructor[0];
        } else {
            res = getDeclaredConstructors0(publicOnly);
        }
        if (useCaches) {
            if (publicOnly) {
                publicConstructors = new SoftReference(res);
            } else {
                declaredConstructors = new SoftReference(res);
            }
        }
        return res;
    }

The control goes through the the lines marked in BOLD.The res variable's value is coming as null.The method getDeclaredConstructors0(publicOnly) is returning null.

I tried to look into what is there in this method.But its just declared as

private native Constructor[] getDeclaredConstructors0(boolean publicOnly);

I am not able to get what is happening.Please help me out.

Just put it in a separate file and make it public. You're working with java and spring; just get used to having billions of files.

.

In the end as per your above comment, is it that we cannot use inner classes when using java and spring ???

Thanks,
Jignesh

Thanks.

[Jörg Heinicke]

The reason for your error is not a protected/public thing (at least as far as I know Spring can access protected methods, constructors, classes) but a static/non-static thing as also the move to an extra file clearly shows. It's a plain Java issue and has nothing to do with Spring. You can't instantiate the inner bean CustomerBeanValidator without having an instance of CustomerBean. That's also why it is complaining about "no default constructor found" since it is technically something like new CustomerBeanValidator(customerBean). You can try it out on the Java level with new CustomerBeanValidator() when you are not in an instance of CustomerBean (but in a static method of it or a unrelated class). The compiler will complain.

public static void main(String[] args) {
    CustomerBeanValidator validator = new CustomerBeanValidator(); // compiler error
    CustomerBeanValidator validator = new CustomerBean.CustomerBeanValidator(); // still compiler error
    CustomerBeanValidator validator = new CustomerBean().new CustomerBeanValidator(); //will work
}

The longer the speech, the less thought: make your inner bean a nested bean by using the modifier static and it will work.

Joerg

[Jörg Heinicke]

Your setup was completely correct as fas as I could see it. You only need to change the line

protected class CustomerBeanValidator implements Validator

into

protected static class CustomerBeanValidator implements Validator

Joerg

[lumpynose]

... In the end as per your above comment, is it that we cannot use inner classes when using java and spring ??? ...

Sorry, Joerg obviously understands these things better than I do. I get frustrated with all of the classes I have to create to do the simplest stuff.

[sushil]

Hi,
I am facing a problem while using the AOP (proxy factory bean usage) for logging mechanism...
i am new to string to not well versed with the nitty grity...

my Application context looks as below...
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd">

<beans>
<bean id="contentService" class="com.toro.service.dctm.content.ContentServic eImpl">
<property name="contentDao" ref="contentDAO" />
<property name="authenticationDao" ref="authenticationDAO" />
<property name="zipFilePath" value="C:\\ContentZip" />
</bean>

<bean id="authenticationDAO" class="com.toro.service.dctm.authentication.dao.Au thenticationDAOImpl"></bean>
<!-- Configure spring to give a hook to axis2 without a ServletContext -->
<bean id="applicationContext" class="org.apache.axis2.extensions.spring.receiver s.ApplicationContextHolder" ></bean>

<bean id="loggingInterceptor" class="com.toro.service.dctm.util.LoggingIntercept or"/>
<!-- <bean id="contentDAO" class="com.toro.service.dctm.content.dao.ContentDa oImpl" />-->


<bean id="contentDAO" class="org.springframework.aop.framework.ProxyFact oryBean" >
<property name="proxyTargetClass" value="true"/>
<property name="proxyInterfaces" >
<value>com.toro.service.dctm.content.dao.ContentDa o</value>
</property>
<property name="target">
<bean class="com.toro.service.dctm.content.dao.ContentDa oImpl" />
</property>
<property name="interceptorNames">
<list>
<value>loggingInterceptor</value>
</list>
</property>
</bean>

</beans>


the Logger class (oggingInterceptor bean) is as below

package com.toro.service.dctm.util;

import java.lang.reflect.Method;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.aop.AfterReturningAdvice;
import org.springframework.aop.MethodBeforeAdvice;
import org.springframework.aop.ThrowsAdvice;

public class LoggingInterceptor implements MethodBeforeAdvice, AfterReturningAdvice, ThrowsAdvice{
private static Log log = null;
public LoggingInterceptor(){
}

public void before(Method arg0, Object[] arg1, Object arg2) throws Throwable {
log = LogFactory.getLog(arg2.getClass());
log.debug("Beginning method: "+arg0.getName());
System.out.println("In The LoggingInterceptor Before Method...");
}

public void afterReturning(Object arg0, Method arg1, Object[] arg2, Object arg3) throws Throwable {
log = LogFactory.getLog(arg3.getClass());
log.info("Ending method: "+arg1.getName());
System.out.println("In The LoggingInterceptor afterReturningx Method...");
}

public void afterThrowing(Method m, Object[] args, Object target, Throwable ex){
log = LogFactory.getLog(target.getClass());
log.info("Exception in method: "+m.getName()+" Exception is: "+ex.getMessage());
}
}


now i am facing a problem while instantiating the contentService class as this has got the refrence to the contentDAO which is supposed to be aproxy...
the error message i am getting is as below..

I am totally lost as what need to be done to fix this issue...
Please let me know...


org.springframework.beans.factory.BeanCreationExce ption: Error creating bean with name 'contentService' defined in class path resource [contentServiceContext.xml]: Cannot resolve reference to bean 'contentDAO' while setting bean property 'contentDao'; nested exception is org.springframework.beans.factory.BeanCreationExce ption: Error creating bean with name 'contentDAO' defined in class path resource [contentServiceContext.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationExcepti on: Could not instantiate bean class [org.springframework.aop.framework.ProxyFactoryBean]: Constructor threw exception; nested exception is java.lang.NoSuchMethodError: org.springframework.util.ClassUtils.isPresent(Ljav a/lang/StringZ
org.springframework.beans.factory.BeanCreationExce ption: Error creating bean with name 'contentDAO' defined in class path resource [contentServiceContext.xml]: Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationExcepti on: Could not instantiate bean class [org.springframework.aop.framework.ProxyFactoryBean]: Constructor threw exception; nested exception is java.lang.NoSuchMethodError: org.springframework.util.ClassUtils.isPresent(Ljav a/lang/StringZ
org.springframework.beans.BeanInstantiationExcepti on: Could not instantiate bean class [org.springframework.aop.framework.ProxyFactoryBean]: Constructor threw exception; nested exception is java.lang.NoSuchMethodError: org.springframework.util.ClassUtils.isPresent(Ljav a/lang/StringZ
java.lang.NoSuchMethodError: org.springframework.util.ClassUtils.isPresent(Ljav a/lang/StringZ
at

[Marten Deinum]

First when posting code please use the [ code][/code ] tags!!! It makes your post readable, which it really isn't right now.

Regarding your error you seem to have a version/classloading issue. Make sure you have all the right versions in your classpath and not 2 versions of the spring.jar.

[sushil]

i have following jars for string in place..
spring.jar
spring-beans.jar
spring-context.jar
spring-core.jar
spring-dao.jar
spring-hibernate.jar
spring-jdbc.jar
spring-mock.jar
spring-orm.jar
spring-web.jar
spring-webmvc.jar
and one for axis..
axis2-spring-1.1.1.jar
and the rest of the jars...
so i dont think there is problem of version conflict...

[pmularien]

I would delete spring*.jar and copy a fresh copy from your Spring download/distribution. The problem is most definitely caused by a version mismatch somewhere. Also, if you are running in an app server, make sure that spring*.jar lives nowhere else in the app server (for e.g. server/lib, common/lib, etc).