#Autowired annotation - spring

Question

I have written a small code to check #Autowired annotation in Spring, here is my piece of code
public class Address
{
private String street;
private String City;
private String State;
private String Country;
/* getter setter here */
}
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
public class Customer
{
private String name;
private Address address;
// other getter setter here
#Autowired
public void setAddress(Address address)
{
this.address = address;
}
}
and springexample.xml 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"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd">
<bean id="address1" class="org.springexamples.Address">
<property name="street" value="vihar" />
<property name="city" value="dehradun" />
<property name="state" value="Uttarakhand" />
<property name="country" value="India" />
</bean>
<bean id="addres2" class="org.springexamples.Address">
<property name="street" value="triveni vihar" />
<property name="city" value="dehradun" />
<property name="state" value="Uttarakhand" />
<property name="country" value="India" />
</bean>
<bean id="customer" class="org.springexamples.Customer">
<property name="name" value="deepak" />
</bean>
<bean class="org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor" />
</beans>
and main class
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class AutowiredQualifierTest
{
public static void main(String[] args)
{
ApplicationContext context= new ClassPathXmlApplicationContext("springexample.xml");
Customer cust = (Customer)context.getBean("customer");
System.out.println(cust.getName() + " " + cust.getAddress().getStreet());
}
}
Ideally it should show an exception as two beans of the same type exist however its picking up bean with id="address1" so i am getting this bean behaviour.

Answer 1

No unique bean of type [org.springexamples.Address] is defined: expected single matching bean but found 2: [address1, addres2]..exception is coming..and it is clearly saying right..so you have to use #Qualifier(your_required_beanid)
for example:
#Qualifier("Address1")
then it will consider id with address1 bean

Answer 2

The exception is thrown. I bet you are doing something wrong. I have tested you code, just to be hundred percent sure and it throws the exception.
Let's take a look to the documentation:
3.4.5.1 Limitations and disadvantages of autowiring
Multiple bean definitions within the container may match the type specified by the setter method or constructor argument to be autowired. For arrays, collections, or Maps, this is not necessarily a problem. However for dependencies that expect a single value, this ambiguity is not arbitrarily resolved. If no unique bean definition is available, an exception is thrown
Also, take a look to this post.

Answer 3

This will give you exception, when spring tries to autoware the address field, it will not find any bean with id address ...rather user Qualifer with proper id so that while autowaring it will pinck the porper object of address from 2 id [address1, address2].