Question

I have a bean mongoService which looks like as

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:util="http://www.springframework.org/schema/util"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-2.0.xsd">

    <context:property-placeholder location="file:///storage//local.properties"/>
    <bean id="mongoService" class="com.business.persist.MongoService">
    <constructor-arg value="${host}"/>
    <constructor-arg value="${port}"/>
    <constructor-arg value="${database}"/>
    </bean>
</beans>   

• I need to include this bean in a separate project so I created a jar for this project and added as maven dependency which looks like

      <dependency>
          <groupId>com.project</groupId>
          <artifactId>business</artifactId>
          <version>master-SNAPSHOT</version>
      </dependency>   
  

• Now in the file where I need to inject this field, I do the following

public class DocumentSaver implements IDocumentSaver {
    @Resource
    private MongoService mongoService;

    public boolean addDocument(Document doc) {
       // do other things

       // add document to mongo   
       mongoService.putDocument(document);

       return true;
    }
}  

and then I run the test as follows

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("/com/wireup.xml")
public class DocumentSaverTest extends DocumentCase {

    @Test
    public void loadAndSave() {
             DocumentSaver saver = new DocumentSaver();
             Document doc = new Document();
             // fill the doc
             saver.addDocument(doc);
        }
}  

I see the NullPointerException when I run this on the like saver.addDocument(doc);

Please tell me what is that I am doing incorrectly

Thank you

Answer 1

You should not create “DocumentSaver” with NEW operator as follows, get that from Spring Application Context.

DocumentSaver saver = new DocumentSaver();

If you use NEW operation , Spring would not inject the dependent objects.