我有一些测试,如果某些Guice范围被错误地使用,我想失败.例如,@Singleton不应该有任何@RequestScoped或@TestScoped依赖关系(当然,Provider也可以).
在生产中,这部分解决了,因为在进入范围之前将构建热切的单例,导致OutOfScopeExceptions.但在发展中,单身人士将在范围内懒洋洋地创造,没有任何问题明显.
根据these two开放问题,似乎没有简单的内置方式来做到这一点.可以用SPI实现吗？我尝试使用一个TypeListener,但不清楚如何获得给定类型的依赖项.
解决方法
这不是一个微不足道的问题,但绝对是一个很好的问题！可能会有一个测试人员提到的范围约束问题.我想我可以让Junit跑步者用错误的绑定练习来产生警告.我稍后会更新这篇文章.
现在有一个如何获取绑定范围的示例.
模
public class ScopeTestModel extends ServletModule {
@Override
protected void configureServlets() {
super
.configureServlets();
bind(Key.get(Object.class,Names.named("REQ1"))).to(Object.class).in(ServletScopes.REQUEST);
bind(Key.get(Object.class,Names.named("REQ2"))).to(RequestScopedObject.class);
bind(Key.get(Object.class,Names.named("SINGLETON1"))).to(Object.class).asEagerSingleton();
bind(Key.get(Object.class,Names.named("SINGLETON2"))).to(Object.class).in(Scopes.SINGLETON);
bind(Key.get(Object.class,Names.named("SINGLETON3"))).to(SingletonScopedObject.class);
bind(Key.get(Object.class,Names.named("SESS1"))).to(Object.class).in(ServletScopes.SESSION);
bind(Key.get(Object.class,Names.named("SESS2"))).to(SessionScopedObject.class);
}
}
测试用例
public class TestScopeBinding {
private Injector injector = Guice.createInjector(new ScopeTestModel());
@Test
public void testRequestScope() throws Exception {
Binding<Object> req1 = injector.getBinding(Key.get(Object.class,Names.named("REQ1")));
Binding<Object> req2 = injector.getBinding(Key.get(Object.class,Names.named("REQ2")));
Scope scope1 = getScopeInstanceOrNull(req1);
Scope scope2 = getScopeInstanceOrNull(req2);
Assert.assertEquals(ServletScopes.REQUEST,scope1);
Assert.assertEquals(ServletScopes.REQUEST,scope2);
}
@Test
public void testSessionScope() throws Exception {
injector.getAllBindings();
Binding<Object> sess1 = injector.getBinding(Key.get(Object.class,Names.named("SESS1")));
Binding<Object> sess2 = injector.getBinding(Key.get(Object.class,Names.named("SESS2")));
Scope scope1 = getScopeInstanceOrNull(sess1);
Scope scope2 = getScopeInstanceOrNull(sess2);
Assert.assertEquals(ServletScopes.SESSION,scope1);
Assert.assertEquals(ServletScopes.SESSION,scope2);
}
@Test
public void testSingletonScope() throws Exception {
injector.getAllBindings();
Binding<Object> sng1 = injector.getBinding(Key.get(Object.class,Names.named("SINGLETON1")));
Binding<Object> sng2 = injector.getBinding(Key.get(Object.class,Names.named("SINGLETON2")));
Binding<Object> sng3 = injector.getBinding(Key.get(Object.class,Names.named("SINGLETON3")));
Scope scope1 = getScopeInstanceOrNull(sng1);
Scope scope2 = getScopeInstanceOrNull(sng2);
Scope scope3 = getScopeInstanceOrNull(sng3);
Assert.assertEquals(Scopes.SINGLETON,scope1);
Assert.assertEquals(Scopes.SINGLETON,scope2);
Assert.assertEquals(Scopes.SINGLETON,scope3);
}
private Scope getScopeInstanceOrNull(final Binding<?> binding) {
return binding.acceptScopingVisitor(new DefaultBindingScopingVisitor<Scope>() {
@Override
public Scope visitScopeAnnotation(Class<? extends Annotation> scopeAnnotation) {
throw new RuntimeException(String.format("I don't know how to handle the scopeAnnotation: %s",scopeAnnotation.getCanonicalName()));
}
@Override
public Scope visitNoScoping() {
if(binding instanceof LinkedKeyBinding) {
Binding<?> childBinding = injector.getBinding(((LinkedKeyBinding)binding).getLinkedKey());
return getScopeInstanceOrNull(childBinding);
}
return null;
}
@Override
public Scope visitEagerSingleton() {
return Scopes.SINGLETON;
}
public Scope visitScope(Scope scope) {
return scope;
}
});
}
}
范围对象
@RequestScoped
public class RequestScopedObject extends Object {
}
@SessionScoped
public class SessionScopedObject extends Object {
}
@Singleton
public class SingletonScopedObject extends Object {
}
