Question

When trying to run a junit test I get the following error –

java.lang.ClassCastException: business.Factory cannot be cast to services.itemservice.IItemsService
at business.ItemManager.get(ItemManager.java:56)
at business.ItemMgrTest.testGet(ItemMgrTest.java:49)

The specific test that is causing the problem is

@Test
public void testGet() {
        Assert.assertTrue(itemmgr.get(items));
}

The code it is testing is…

public boolean get(Items item)  { 

        boolean gotItems = false;       

        Factory factory = Factory.getInstance();

        @SuppressWarnings("static-access")
        IItemsService getItem = (IItemsService)factory.getInstance();

        try {
            getItem.getItems("pens", 15, "red", "gel");
            gotItems = true;
        } catch (ItemNotFoundException e) {
            // catch
            e.printStackTrace();
            System.out.println("Error - Item Not Found");
        }
        return gotItems;
    }

The test to store items, which is nearly identical, works just fine…

The factory class is..

public class Factory {

    private Factory() {}
    private static Factory Factory = new Factory();
    public static Factory getInstance() {return Factory;}




    public static IService getService(String serviceName) throws ServiceLoadException {
        try {
            Class<?> c = Class.forName(getImplName(serviceName));
            return (IService)c.newInstance();
        } catch (Exception e) {
            throw new ServiceLoadException(serviceName + "not loaded");
        }
    }



    private static String getImplName (String serviceName) throws Exception {
        java.util.Properties props = new java.util.Properties();
            java.io.FileInputStream fis = new java.io.FileInputStream("config\\application.properties");
                props.load(fis);
                    fis.close();
                    return props.getProperty(serviceName);
}
}

Answer 1

Your Factory.getInstance method returns a Factory object, and Factory is not IItemsService. Maybe you need to change the following:

@SuppressWarnings("static-access")
IItemsService getItem = (IItemsService)factory.getInstance();

to:

@SuppressWarnings("static-access")
IItemsService getItem = (IItemsService)factory.getService(serviceName);