I am getting the following compilation error in eclipse when trying to instantiate an ObjectFactory: 

```
cannot instantiate the type objectfactory

```

This compilation error is thrown at the following line: 

```
objectFactory = new ObjectFactory();//throws error: "Cannot instantiate the type ObjectFactory"

```

The complete code for the calling class is as follows: 

```
package maintest;

import java.io.File;
import javax.naming.spi.ObjectFactory;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBElement;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Unmarshaller;

public class Main {

    private static JAXBContext context;
    private static ObjectFactory objectFactory;

    public static void main(String[] args) {
        try {setUp();} catch (Exception e) {e.printStackTrace();}
        unmarshal();
    }

    protected static void setUp() throws Exception {
        context = JAXBContext.newInstance("generated");
        objectFactory = new ObjectFactory();//throws error: "Cannot instantiate the type ObjectFactory"
    }

    public static <PurchaseOrderType> void unmarshal(){
        Unmarshaller unmarshaller;
        try {
            unmarshaller = context.createUnmarshaller();
            final Object object = unmarshaller.unmarshal(new File("src/test/samples/po.xml"));
        } catch (JAXBException e) {e.printStackTrace();}
    }
}

```

**How can I resolve this error?**