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How to convert an xml config bean to java annotation bean ( spring boot )

I am new to java AOP. I am supposed to convert the following xml config to java annotation config in my spring boot application. May I know how exactly to convert this xml config to java annotation config:
I think none of the examples that I saw in stackoverflow match the pattern I am trying to convert.
<bean id="xyzRestTemplate"
class="org.springframework.web.client.RestTemplate">
<constructor-arg ref="xyzClientHttpRequestFactory" />
<property name="messageConverters">
<list>
<bean class="org.springframework.http.converter.xml.MarshallingHttpMessageConverter">
<property name="marshaller" ref="jaxbDataMarshaller" />
<property name="unmarshaller" ref="jaxbDataMarshaller" />
</bean>
</list>
</property>
<property name="interceptors">
<list>
<bean class="com.example.XYZHeaderRequestInterceptor" />
</list>
</property>
</bean>
<bean id="jaxbDataMarshaller" class="org.springframework.oxm.jaxb.Jaxb2Marshaller">
<property name="contextPaths">
<list>
<value>com.a.b.c.d.v2</value>
</list>
</property> </bean>

When people talk about converting from XML they don't mean necessarily doing the same thing exactly. What makes Spring Boot attractive isn't just that a configuration is a java class.
You should convert this to use RestTemplate https://docs.spring.io/spring-boot/docs/current/reference/html/boot-features-resttemplate.html
Then you just build the RestTemplate using the builder to have the JaxB marshaller and the interceptor you want.
Rest Template - XML Indentation
A nice testcase that passes with XML and passes with #Configuration classes will prove you got it right.

Java Spring IOC bean creation value

I need a bean like this
<bean id="studentWithSchool" class="com.model.Student" scope="prototype">
<property name="school">
<bean class="com.model.School" scope="prototype"/>
</property>
</bean>
This is OK.
My problem is I have the student returning from a method from a different bean.
I usually load the bean like this when is a property.
<property name='beanProperty' value='#{anotherBean.getBeanProperty()}'/>
But in this case I need the new bean itself being set from the other bean method (School object is returned from another bean method).
This is what I try, and of course this is wrong:
<bean id="studentWithSchool" class="com.model.Student" scope="prototype" value='#{anotherBean.getBeanProperty()}'>
<property name="school">
<bean class="com.model.School" scope="prototype"/>
</property>
</bean>
Is there any workaround?

If I understand you correctly, the studentWithSchool is created and returned by a method in anotherBean. If that's the case, you can use a factory-method:
<bean id="studentWithSchool" factory-bean="anotherBean" factory-method="getBeanProperty" scope="prototype" />

I believe you are trying to use factory patter with Spring . For that you can use factory bean from spring.
<bean id="studentWithSchool" factory-bean="anotherBeanStaticFactory" factory- method="createBeanProperty" scope="prototype"
<property name="school">
<bean class="com.model.School" scope="prototype"/>
</property>
For more detail you can use below link :-
http://docs.spring.io/spring-framework/docs/2.5.6/api/org/springframework/beans/factory/BeanFactory.html

Inject entity manager from XML in Spring

I need to do very similar thing to what is described in Injecting Entitymanager via XML and not annnotations, but I need to inject from XML the real, container-created, entity manager, so that it behaves exactly as if there is a real #PersistenceContext annotation. I've found a LocalEntityManagerFactoryBean (notice missing "Container" word), but I'm affraid that it creates a new entity manager factory and therefore entity manager won't be compatible with that injected via real #PersistenceContext annotation.
I will describe the reason, because it is weird and maybe the solution to my problem is to choose completely different approach. I'm using PropertyPlaceholderConfigurer in my spring configuration and in this configurer I'm referencing other beans. I'm experiencing a bug that autowiring doesn't work in those referenced beans. I don't know why and how PropertyPlaceholderConfigurer turns off autowiring in those referenced beans but the fact is, that if I replace autowiring by xml configuration for those beans, everything works. But I'm unable to replace autowiring of EntityManager, since it's not standard spring bean, but jndi-loaded something I don't fully understand.
One way or the other, is there some solution?

in spring-bean.xml ,
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="persistenceUnitName" value="USER_TEST"/>
<property name="jpaVendorAdapter" ref="jpaVendorAdapter"/>
<property name="jpaDialect">
<bean class="org.springframework.orm.jpa.vendor.EclipseLinkJpaDialect"/>
</property>
<property name="jpaPropertyMap">
<props>
<prop key="eclipselink.weaving">false</prop>
</props>
</property>
<bean id="PersonDao" class="com.xxx.java.person.persistence.PersonDAO">
<property name="entityManagerFactory" ref="entityManagerFactory"/>
</bean>

<bean id="earlyInitializedApplicationSettingsService" class="...services.impl.ApplicationSettingsServiceImpl" autowire-candidate="false">
<property name="applicationSettingsDao">
<bean class="....impl.ApplicationSettingsDaoImpl">
<property name="entityManager">
<bean class="org.springframework.orm.jpa.support.SharedEntityManagerBean">
<property name="entityManagerFactory">
<bean class="org.springframework.jndi.JndiObjectFactoryBean">
<property name="jndiName" value="java:comp/env/persistence/somePersistenceUnit"/>
</bean>
</property>
</bean>
</property>
</bean>
</property>
</bean>
Notice mainly the fact, that I'm not using standard jee:jndi-lookup, because it didn't work (in the conditions created by PropertyPlaceholderConfigurer) and that was the source of my confusion. When I used direct JndiObjectFactoryBean, it worked.

Spring: Getting FactoryBean object instead of FactoryBean.getObject()

Short question: If I have class that impelemnts FactoryBean interface, how can I get from FactoryBean object itself instead of FactoryBean.getObject()?
Long question: I have to use 3-rd party Spring based library which is hardly use FactoryBean interface. Right now I always must configure 2 beans:
<!-- Case 1-->
<bean id="XYZ" class="FactoryBean1" scope="prototype">
<property name="steps">
<bean class="FactoryBean2">
<property name="itemReader" ref="aName"/>
</bean>
</property>
</bean>
<bean id="aName" class="com.package.ClassName1" scope="prototype">
<property name="objectContext">
<bean class="com.package.ABC"/>
</property>
</bean>
<!-- Case 2-->
<bean id="XYZ2" class="FactoryBean1" scope="prototype">
<property name="steps">
<bean class="FactoryBean2">
<property name="itemReader" ref="aName2"/>
</bean>
</property>
</bean>
<bean id="aName2" class="com.package.ClassName1" scope="prototype">
<property name="objectContext">
<bean class="com.package.QWE"/>
</property>
</bean>
Actyually defintion of a bean with name "XYZ" (compare with "XYZ2") never will be changed, but because of factory nature I must copy the code for each configuration.
Definition of a bean with name "aName" always will be new (i.e. each configuration will have own objectContext value).
I would like to simplify the configuration have a single factory bean (remove "XYZ2" and rid of link to "aName"):
<bean id="XYZ" class="FactoryBean1" scope="prototype">
<property name="steps">
<bean class="FactoryBean2"/>
</property>
</bean>
<bean id="aName" class="com.package.ClassName1" scope="prototype">
<property name="objectContext">
<bean class="com.package.ABC"/>
</property>
</bean>
<bean id="aName2" class="com.package.ClassName1" scope="prototype">
<property name="objectContext">
<bean class="com.package.QWE"/>
</property>
</bean>
Unfortunately, it's not as simple as I expect. I suppose to glue factory (i.e. XYZ bean from the example) with necessary objects (i.e. "aName", "aName2") at runtime.
The approach doesn't work because when I ask Spring for FactoryBean object it returns to me FactoryBean.getObject() which impossible to instanciate at that time because of missing itemReader value.
I hope that SpringSource foresee my case I can somehome "hook" FactoryBean.getObject() call to provide all necessary properties at runtime.
Another complexity that disturb me a bit it's chains of Factories (Factory1 get an object from Factory2 that I have to "hook" at runtime).
Any ideas will be appreciated.

It's the & (ampersand), not the At-symbol, see Spring Framework documentation: Customizing instantiation logic using FactoryBeans
<property name="factoryBean" ref="&theFactoryBean" />

You can get the factory bean itself using the & syntax in the spring config:
<property name="factoryBean" ref="&theFactoryBean" />
as opposed to:
<property name="createdBean" ref="theFactoryBean" />

spring: a bean that receives a list of Classes

I want to define in my Spring XML context a bean that has a property of the type List of classes: i.e. List<Class<?>> classes
How do I send that bean a number of classes, say java.lang.String and java.lang.Integer?
The list needs not be reusable, i.e. I will not refer to it in another bean.

With Spring, the simplest possibility usually works.....
<property name="classes">
<list>
<value>java.lang.String</value>
<value>java.lang.Integer</value>
</list>
</property>

<property name="classes">
<list>
<bean class="java.lang.Class" factory-method="forName">
<constructor-arg value="java.lang.String"/>
</bean>
</list>
</property>
Something like that...