Spring NullPointerException while injecting Map - spring

Question

I am trying to inject a Map into a UtilityClass. I have created a Map Bean and I am injecting it using #Resource annotation.
#Configuration
class MyConfiguration {
#Bean
Map<String, String> testMap(){
def map = [:] // Using groovy
// Putting things into map
map
}
}
#Component
class MyUtilityClass {
#Resource(name="testMap")
Map<String, String> testMap
}
I am getting following error:
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'testMap' defined in com.my.company.config.MyConfiguration: Initialization of bean failed; nested exception is java.lang.NullPointerException
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:547) ~[spring-beans-4.1.5.RELEASE.jar:4.1.5.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476) ~[spring-beans-4.1.5.RELEASE.jar:4.1.5.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303) ~[spring-beans-4.1.5.RELEASE.jar:4.1.5.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.1.5.RELEASE.jar:4.1.5.RELEASE]
.....
Caused by: java.lang.NullPointerException
at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:571) ~[spring-core-4.1.5.RELEASE.jar:4.1.5.RELEASE]
at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:490) ~[spring-core-4.1.5.RELEASE.jar:4.1.5.RELEASE]
at org.springframework.util.ReflectionUtils.doWithMethods(ReflectionUtils.java:474) ~[spring-core-4.1.5.RELEASE.jar:4.1.5.RELEASE]
Am I doing something wrong here while injecting the Map. Not sure why the NPE is caused?
UPDATE -
So created a class and added the Map as an attribute of that class. And injected that class as a Bean. It worked correctly and it could inject the Class with the Map in it.
#Configuration
class MyConfiguration {
#Bean
Testclass testClass(){
def map = [:] // Using groovy
// Putting things into map
new TestClass(testMap: map)
}
}
class TestClass {
Map<String, String> testMap
}
So seems like the issue is in the Map being injected.