我正在为aem中的sling模型做一个非常基本的单元测试，因此，当我运行测试时，我得到以下错误：
[错误]ctamodeltest.testgettext:36 nullpointer
这是我的java代码，这个模型是一个非常基本的sling aem模型，我使用 @ModelAnnotation 具体如下：

@Model(adaptables = SlingHttpServletRequest.class, defaultInjectionStrategy = DefaultInjectionStrategy.OPTIONAL)

package com.myproject.core.models;
import org.apache.commons.lang3.StringUtils;
import org.apache.sling.api.resource.Resource;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import com.day.cq.wcm.api.Page;
import io.wcm.testing.mock.aem.junit5.AemContext;
import io.wcm.testing.mock.aem.junit5.AemContextExtension;
import static org.junit.jupiter.api.Assertions.assertNotNull;
import static org.junit.jupiter.api.Assertions.assertTrue;
import junitx.util.PrivateAccessor;
import javax.inject.Inject;

@ExtendWith(AemContextExtension.class)
class CtaModelTest {
    private static final String COMPONENT_PATH = "/content/campaigns/myproject/master/demo-campaign/demo-email";

    private CtaModel ctaModel;

    private Page page;
    private Resource resource;

    @BeforeEach
    public void setup(AemContext context) throws Exception {

        context.load().json("/ctaModelTest.json", COMPONENT_PATH);
        context.addModelsForClasses(CtaModel.class);

        resource = context.resourceResolver().getResource(COMPONENT_PATH + "/jcr:content/par/hero/cta");
        ctaModel = resource.adaptTo(CtaModel.class);
    }

    @Test
    void testGetText() throws Exception {
        String txt = ctaModel.getText();
        assertNotNull(txt);
    }
}

有人能帮我修一下吗？