模拟FacesContext

Question

我正在尝试向JSF应用程序添加一些单元测试。该应用程序不太依赖于任何最佳实践，因此许多服务方法使用FacesContext从托管会话beans中提取数据，如下所示：

(这是在一个util类中)

  public static Object getPageBean(String beanReference) {
      FacesContext fc = FacesContext.getCurrentInstance();
      VariableResolver vr = fc.getApplication().getVariableResolver();
      return vr.resolveVariable(fc, beanReference);
  }

模拟这种情况最好的方式是什么？我使用的是groovy，所以我有更多的选择来创建我不能正常创建的类。

Answer 1

在我的例子中，我可以用纯groovy来模拟它。我提供了一个它可以返回的MockBeans地图：

private FacesContext getMockFacesContext(def map){
        def fc = [
          "getApplication": {
            return ["getVariableResolver": {
              return ["resolveVariable": { FacesContext fc, String name ->
                return map[name]
              }] as VariableResolver
            }] as Application
          },
          "addMessage": {String key, FacesMessage val ->
            println "added key: [${key}] value: [${val.getDetail()}] to JsfContext messages"
          },
          "getMessages": {return null}
        ] as FacesContext;
        return fc;
      }

Answer 2

您可以在运行测试之前调用setCurrentInstance(FacesContext)，通过FacesContext.getCurrentInstance返回模拟上下文。该方法是受保护的，但您可以通过反射或扩展FacesContext来访问它。这里有一个使用Mockito here的示例实现。

Answer 3

这个网址提供了一篇关于它的非常好的文章：http://illegalargumentexception.blogspot.com/2011/12/jsf-mocking-facescontext-for-unit-tests.html

您有了托管bean：

 package foo;

import java.util.Map;

import javax.faces.bean.ManagedBean;
import javax.faces.bean.RequestScoped;
import javax.faces.context.FacesContext;

@ManagedBean
@RequestScoped
public class AlphaBean {
  public String incrementFoo() {
    Map<String, Object> session = FacesContext.getCurrentInstance()
        .getExternalContext()
        .getSessionMap();
    Integer foo = (Integer) session.get("foo");
    foo = (foo == null) ? 1 : foo + 1;
    session.put("foo", foo);
    return null;
  }
}

您可以将FacesContext存根：

package foo.test;

import javax.faces.context.FacesContext;

import org.mockito.Mockito;
import org.mockito.invocation.InvocationOnMock;
import org.mockito.stubbing.Answer;

public abstract class ContextMocker extends FacesContext {
  private ContextMocker() {
  }

  private static final Release RELEASE = new Release();

  private static class Release implements Answer<Void> {
    @Override
    public Void answer(InvocationOnMock invocation) throws Throwable {
      setCurrentInstance(null);
      return null;
    }
  }

  public static FacesContext mockFacesContext() {
    FacesContext context = Mockito.mock(FacesContext.class);
    setCurrentInstance(context);
    Mockito.doAnswer(RELEASE)
        .when(context)
        .release();
    return context;
  }
}

然后编写你的单元测试：

@Test
  public void testIncrementFoo() {
    FacesContext context = ContextMocker.mockFacesContext();
    try {
      Map<String, Object> session = new HashMap<String, Object>();
      ExternalContext ext = mock(ExternalContext.class);
      when(ext.getSessionMap()).thenReturn(session);
      when(context.getExternalContext()).thenReturn(ext);

      AlphaBean bean = new AlphaBean();
      bean.incrementFoo();
      assertEquals(1, session.get("foo"));
      bean.incrementFoo();
      assertEquals(2, session.get("foo"));
    } finally {
      context.release();
    }
  }