CDI/Weld无法对RESTEasy资源进行构造函数注入

Question

我正在尝试将RESTEasy与Weld结合在AppEngine上,但是在构造函数注入方面遇到了麻烦.

我添加了RESTEasy CdiInjectorFactory上下文参数和Weld servlet侦听器.

我的RESTEasy应用程序类看起来像:

public class MyApplication extends Application {

    @Override
    public Set<Class<?>> getClasses() {
        HashSet<Class<?>> classes = new HashSet<Class<?>>();
        classes.add(CustomerResource.class);
        return classes;
    }
}

和CustomerResource:

@Path("/rest/app/customers")
public class CustomerResource {

    private final CustomerService customerService;

    @Inject
    public CustomerResource(CustomerService customerService) {
        this.customerService = customerService;
    }

    ..
}

CustomerService是一项简单的服务,例如:

public class CustomerService {

    public List<Customer> getCustomers() {
        ..
    }
}

当我启动服务器时,我在日志中看到:

[INFO] 2014-01-30 21:34:53 INFO  org.jboss.weld.Version:146 - WELD-000900: 2.1.2 (Final)
[INFO] 2014-01-30 21:34:53 WARN  org.jboss.weld.environment.servlet.Listener:137 - @Resource injection not available in simple beans
[INFO] 2014-01-30 21:34:54 INFO  org.jboss.weld.Bootstrap:199 - WELD-000101: Transactional services not available. Injection of @Inject UserTransaction not available. Transactional observers will be invoked synchronously.
[INFO] 2014-01-30 21:34:55 DEBUG org.jboss.resteasy.cdi.ResteasyCdiExtension:68 - Discovered CDI bean which is javax.ws.rs.core.Application subclass com.mycomp.config.MyApplication.
[INFO] 2014-01-30 21:34:55 DEBUG org.jboss.resteasy.cdi.ResteasyCdiExtension:68 - Bean class com.mycomp.config.MyApplication does not have the scope defined. Binding to @javax.enterprise.context.ApplicationScoped().
[INFO] 2014-01-30 21:34:55 DEBUG org.jboss.resteasy.cdi.ResteasyCdiExtension:68 - Discovered CDI bean which is a JAX-RS resource com.mycomp.rest.app.CustomerResource.
[INFO] 2014-01-30 21:34:55 DEBUG org.jboss.resteasy.cdi.ResteasyCdiExtension:68 - Bean class com.mycomp.rest.app.CustomerResource does not have the scope defined. Binding to @javax.enterprise.context.RequestScoped().
[INFO] 2014-01-30 21:34:55 INFO  org.jboss.weld.environment.servlet.Listener:147 - No supported servlet container detected, CDI injection will NOT be available in Servlets, Filters or Listeners
[INFO] 2014-01-30 21:34:56 WARN  org.jboss.weld.Interceptor:47 - WELD-001700: Interceptor annotation class javax.ejb.PostActivate not found, interception based on it is not enabled
[INFO] 2014-01-30 21:34:56 WARN  org.jboss.weld.Interceptor:47 - WELD-001700: Interceptor annotation class javax.ejb.PrePassivate not found, interception based on it is not enabled

通过此日志记录,我可以看到我的RESTEasy应用程序和资源类已被发现.请注意,我没有看到有关CustomerService的任何提及.

当我在浏览器中访问我的资源时,我得到:

[INFO] 2014-01-30 21:47:26 DEBUG org.jboss.resteasy.cdi.CdiInjectorFactory:68 - Using CdiConstructorInjector for class class com.mycomp.config.MyApplication.
[INFO] 2014-01-30 21:47:26 DEBUG org.jboss.resteasy.cdi.CdiConstructorInjector:68 - Beans found for class com.mycomp.config.MyApplication : [Managed Bean [class com.mycomp.config.MyApplication] with qualifiers [@Any @Default]]
[INFO] 2014-01-30 21:47:26 INFO  org.jboss.resteasy.spi.ResteasyDeployment:82 - Deploying javax.ws.rs.core.Application: class com.mycomp.config.MyApplication$Proxy$_$$_WeldClientProxy
[INFO] 2014-01-30 21:47:26 INFO  org.jboss.resteasy.spi.ResteasyDeployment:82 - Adding class resource com.mycomp.rest.app.CustomerResource from Application class com.mycomp.config.MyApplication$Proxy$_$$_WeldClientProxy
[INFO] 2014-01-30 21:47:26 INFO  org.jboss.resteasy.spi.ResteasyDeployment:82 - Adding class resource com.mycomp.rest.HeartbeatResource from Application class com.mycomp.config.MyApplication$Proxy$_$$_WeldClientProxy
[INFO] Jan 30, 2014 9:47:26 PM com.google.appengine.tools.development.ApiProxyLocalImpl log
[INFO] SEVERE: javax.servlet.ServletContext log: unavailable
[INFO] java.lang.RuntimeException: Could not find constructor for class: com.mycomp.rest.app.CustomerResource

RESTEasy是否尝试创建一个新的CustomerResource实例而不是从Weld中选择它？

我也尝试过使用字段注入(而不是构造函数注入),然后我可以看到CustomerService很好地注入了CustomerResource.

我只是更喜欢构造函数注入,并想知道在使用Weld时RESTEasy资源类是否支持它？

Answer 1

JAX-RS需要一个没有arg构造函数的余资源.您可以拥有其他构造函数,但您还需要一个无参数构造函数.