Method Injection - getting NullPointerException

[vikas_chess]

Method Injection is used for singleton-scoped bean to acquire a new instance of the prototype-scoped bean as explained here

While trying this, I got NullPointerException. Please find below the code.

I am using Spring 3.0.

spring-context.xml

	<bean id="student" class="com.spring.demo.Student" scope="prototype" />

	<bean id="college" class="com.spring.demo.College" scope="singleton" p:student-ref="student" />

College.java

public class College implements ApplicationContextAware {

	private ApplicationContext applicationContext;

	private Student student;

	public void setStudent(Student student) {
		this.student = applicationContext.getBean("student", Student.class);
	}

	public Student getStudent() {
		return student;
	}

	@Override
	public void setApplicationContext(ApplicationContext applicationContext)
			throws BeansException {
		this.applicationContext = applicationContext;
	}
}

Student.java

public class Student {

	public Student() {
		System.out.println("Student constructor...");
	}
}

test code:

		ConfigurableApplicationContext appContext = new ClassPathXmlApplicationContext(
				"/spring-context.xml");
		College col = appContext.getBean("college", College.class);
		col = appContext.getBean("college", College.class);

I am getting below exception on running test code:

Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'college' defined in class path resource [scope-context.xml]: Error setting property values; nested exception is org.springframework.beans.PropertyBatchUpdateException; nested PropertyAccessExceptions (1) are:
PropertyAccessException 1: org.springframework.beans.MethodInvocationException: Property 'student' threw exception; nested exception is java.lang.NullPointerException
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1363)Student constructor...

	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1085)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:516)

[vikas_chess]

ok i resolved the issue!

setStudent method of class College was getting called before setApplicationContext because setter injection is called first in Spring. Thats why null pointer exception on applicationContext object.

I have resolved the issue by creating ApplicationContextUtil that implements ApplicationContextAware and getting reference of applicationContext from the util class.