Thread: Spring autowired variable is null when accessed from another class

Here's the problem
I have a class A

A.java

public class A {
 
	private Properties properties = new Properties();
 
	private File file;
 
	public File getFile() {
		return file;
	}
 
	public void setFile(File file) {
		this.file = file;
	}
 
	public void init() {
		try{
			properties.load(new FileInputStream(file));
		}catch(IOException e){
 
		}
	}
 
	public String getValue(String key) {
		return properties.getProperty(key);
	}
}

Here's how I insantiate an instance of this class.

test-beans.xml

...
<bean id="a"
		class="com.example.A" init-method="init">
		<property name="file" value="sample.properties"/>
	</bean>
...

There is a class that contains few common methods to be used by a number of other classes

CommonMethods.java

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "/test-beans.xml")
public class CommonMethods {
 
	@Autowired
	private A a;
 
 
	public String getFileName() {
                if(a==null)
                     System.out.println("a is null");
                else
                     System.out.println("a is null");
		String s=a.getFile().getName();
		return(s);
	}
 
         @Test // JUnit test case
          public void testmethod() {
              getFileName();
          }
 
}

There is a test class from which I need to call getFileName()

test.java

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "/test-beans.xml")
public class test {
 
CommonMethods cm = new CommonMethods();
 
@Test
public void testSomething() {
cm.getFileName();
 
 
}

Now here's the problem
When I run testmethod() from CommonMethods.java, I get a is not null.
When I run testSomething() from test.java, I get a is null.

Why is that? Is there a way I can use getFileName() in test.java? Please help!!

Thank you. I made the following changes:-

test-beans.xml

...
<bean id="a"
		class="com.example.A" init-method="init">
		<property name="file" value="sample.properties"/>
	</bean>
 
       <bean id="cm"
		class="com.example.CommonMethods">
		<property name="a" ref="a"/>
	</bean>
....

CommonMethods.java

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "/test-beans.xml")
public class CommonMethods {
 
	@Autowired
	private A a;
 
       public A geta() {
              return(a);
         }
 
          public void seta(A a) {
               this.a=a;
          }
 
	public String getFileName() {
                if(a==null)
                     System.out.println("a is null");
                else
                     System.out.println("a is null");
		String s=a.getFile().getName();
		return(s);
	}
 
         @Test // JUnit test case
          public void testmethod() {
              getFileName();
          }
 
}

test.java

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "/test-beans.xml")
public class test {
 
CommonMethods cm;
 
@Test
public void testSomething() {
cm.getFileName();
 
}

Still getting the same issue. Help me!! What am I doing wrong?