#vulnerable code 
                                @Test
    public void testAnnotatedModel()
    {
        User solomon = DataGenerator.solomon();
        ResultTraverser traverser = new ResultTraverser();

        YogaRequestContext requestContext = new YogaRequestContext( "test",
                new DummyHttpServletRequest(), new DummyHttpServletResponse(), new HrefListener() );
        Map<String, Object> objectTree = doTraverse( solomon, ":", traverser, requestContext );

        Assert.assertEquals( "/user/" + solomon.getId() + ".test", objectTree.get( "href" ) );
    } 
                            #location 11 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                @Test
    public void testAnnotatedModel()
    {
        User solomon = DataGenerator.solomon();
        ResultTraverser traverser = new ResultTraverser();

        YogaRequestContext requestContext = new YogaRequestContext( "test", new GDataSelectorParser(),
                new DummyHttpServletRequest(), new DummyHttpServletResponse(), new HrefListener() );
        Map<String, Object> objectTree = doTraverse( solomon, ":", traverser, requestContext );

        Assert.assertEquals( "/user/" + solomon.getId() + ".test", objectTree.get( "href" ) );
    }