spring batch - Write object data to multiple files - spring

Question

In spring batch, I have a requirement where i have list of customer objects from database and from this list i need to create multiple text files.
clas Customer{
long customerId;
string name;
Address add;
Phone phn;
}
class Address{
string address;
long pincode;
string street;
}
class Phone{
string phoneNumber;
string desc;
}
I want to write the data of each customer to different text files such as
customer.txt -> customerId, name
address.txt -> address, pincode, street
phone.txt -> phoneNumber, desc
i tried using CompositeItemWriter which can delegate object to different writer but i could not get how to retrive specific object or properties in the writer.
I couldnt get any sample or explaination to implement CompositeWriter. can someone please help me with the writer implementation? Is there any other better way of doing it?
Thanks in advance.

Answer 1

I was able to write data of each customer to different text file using CompositeItemWriter. Below is how i did for customer phone extract. I hope it helps someone.
<bean id="compositeCustomerWriter"
class="org.springframework.batch.item.support.CompositeItemWriter">
<property name="delegates">
<list>
<ref bean="customerWriter" />
<ref bean="customerPhoneWriter" />
<ref bean="customerAddressWriter" />
</list>
</property>
</bean>
<bean id="customerPhoneWriter" class="org.springframework.batch.item.file.FlatFileItemWriter">
<property name="resource" value="file:customer_phone_extract.txt" />
<property name="lineAggregator" ref="customerPhonelineAggregator" />
</bean>
<bean id="customerPhonelineAggregator"
class="org.springframework.batch.item.file.transform.DelimitedLineAggregator">
<property name="delimiter" value="|" />
<property name="fieldExtractor">
<bean
class="org.springframework.batch.item.file.transform.BeanWrapperFieldExtractor">
<property name="names"
value="phn.phoneNumber,phn.desc" />
</bean>
</property>
</bean>