如何将JAX-RS与CDI集成在Servlet 3.0容器中 [英] How to integrate JAX-RS with CDI in a Servlet 3.0 container

问题描述

我有一个使用JSF 2.2（Mojorra 2.1.3）& ;;在Servlet 3.0容器（Jetty 9.0.4）上运行的Web应用程序。 CDI 1.1（Weld 2.0.3）。没有使用完整的应用程序服务器。在这个应用程序中，我还有一个服务REST请求的JAX-RS 2.0（Jersey 2.2）资源类。我已经集成了JAXB绑定和JSON编组（Jackson 2.2）。我使用Maven 3.0.5进行构建管理。这些是我的项目设置的相关部分：

Maven pom.xml：

  ... 
< dependencies> 
 
<！ -  Servlet 3.0 API  - > 
< dependency> 
< groupId> javax.servlet< / groupId> 
< artifactId> javax.servlet-api< / artifactId> 
< version> 3.1.0< / version> 
< scope>提供< / scope> 
< / dependency> 
 
<！ -  Java EE的上下文和依赖注入 - > 
< dependency> 
< groupId> org.jboss.weld.servlet< / groupId> 
< artifactId> weld-servlet< / artifactId> 
< version> 2.0.3.Final< / version> 
< / dependency> 
 
<！ -  JavaServer Faces  - > 
< dependency> 
< groupId> com.sun.faces< / groupId> 
< artifactId> jsf-api< / artifactId> 
< version> 2.2.2< / version> 
< / dependency> 
< dependency> 
< groupId> com.sun.faces< / groupId> 
< artifactId> jsf-impl< / artifactId> 
< version> 2.2.2< / version> 
< / dependency> 
 
<！ -  JAX-RS RESTful Web服务 - > 
< dependency> 
< groupId> org.glassfish.jersey.containers< / groupId> 
< artifactId> jersey-container-servlet< / artifactId> 
< version> 2.2< / version> 
< / dependency> 
 
<！ -  JSON Mapping Framework  - > 
< dependency> 
< groupId> com.fasterxml.jackson.core< / groupId> 
< artifactId> jackson-databind< / artifactId> 
< version> 2.2.2< / version> 
< / dependency> 
< dependency> 
< groupId> org.glassfish.jersey.media< / groupId> 
< artifactId> jersey-media-json-jackson< / artifactId> 
< version> 2.2< / version> 
< / dependency> 
< / dependencies> 
 ... 
  

部署描述符web.xml：

  ... 
< context-param> 
< param-name> javax.faces.PROJECT_STAGE< / param-name> 
< param-value>开发< / param-value> 
< / context-param> 
 
< servlet> 
< servlet-name> Faces Servlet< / servlet-name> 
< servlet-class> javax.faces.webapp.FacesServlet< / servlet-class> 
< load-on-startup> 1< / load-on-startup> 
< / servlet> 
 
< servlet-mapping> 
< servlet-name> Faces Servlet< / servlet-name> 
< url-pattern> / jsf / *< / url-pattern> 
< / servlet-mapping> 
 
< servlet> 
< servlet-name> Jersey REST服务< / servlet-name> 
< servlet-class> org.glassfish.jersey.servlet.ServletContainer< / servlet-class> 
< init-param> 
< param-name> javax.ws.rs.Application< / param-name> 
< param-value> my.package.config.RestApplication< / param-value> 
< / init-param> 
< load-on-startup> 1< / load-on-startup> 
< / servlet> 
 
< servlet-mapping> 
< servlet-name> Jersey REST服务< / servlet-name> 
< url-pattern> / rest / *< / url-pattern> 
< / servlet-mapping> 
 
< session-config> 
< session-timeout> 30< / session-timeout> 
< / session-config> 
 
< listener> 
< listener-class> org.jboss.weld.environment.servlet.Listener< / listener-class> 
< / listener> 
 
< listener> 
< listener-class> com.sun.faces.config.ConfigureListener< / listener-class> 
< / listener> 
 
< resource-env-ref> 
< description> CDI Bean Manager的对象工厂< / description> 
< resource-env-ref-name> BeanManager< / resource-env-ref-name> 
< resource-env-ref-type> javax.enterprise.inject.spi.BeanManager< / resource-env-ref-type> 
< / resource-env-ref> 
 ... 
  

JAX-RS根资源类：

  @Path（/ person）
 public class PersonController 
 {
 @Inject 
 private PersonService personService; 
 
 @GET 
 @Produces（{MediaType.APPLICATION_JSON，MediaType.APPLICATION_XML}）
 public List< Person> getAllPersons（）
 {
 return personService.getAll（）; 
} 
 
 @GET 
 @Path（/ {index}）
 @Produces（{MediaType.APPLICATION_JSON，MediaType.APPLICATION_XML}）
 public Person getPerson（@PathParam（index）int index）
 {
 return personService.get（index）; 
} 
 
 @POST 
 @Consumes（{MediaType.APPLICATION_JSON，MediaType.APPLICATION_XML}）
 public void savePerson（Person person）
 {
 personService.add（person）; 
} 
} 
  

JAX-RS应用程序配置：

 公共类RestApplication扩展ResourceConfig 
 {
 public RestApplication（）
 {
 //对于JSON绑定
寄存器（new JacksonFeature（））; 
寄存器（new ApplicationBinder（））; 
包（my.package.controller）; 
} 
} 
  

JAX-RS注入绑定配置：

  public class ApplicationBinder extends AbstractBinder 
 {
 @Override 
 protected void configure （）
 {
 //表示类似：将PersonService类型的注入点处的字段绑定到PersonService 
 bind（PersonService.class）.to（PersonService.class）类型的实例; 
} 
} 
  

最后是JSF托管bean：

  @Named 
 @SessionScoped 
公共类PersonBean实现Serializable 
 {
 private static final long serialVersionUID = 1L; 
 
 @Inject 
 private PersonService personService; 
 
 private person newPerson = new Person（）; 
 
 public List< Person> getAll（）
 {
 return personService.getAll（）; 
} 
 
 public Person getNewPerson（）
 {
 return newPerson; 
} 
 
 public void setNewPerson（Person newPerson）
 {
 this.newPerson = newPerson; 
} 
 
 public性别[] getGenders（）
 {
 return Gender.values（）; 
} 
 
 public String saveNewPerson（）
 {
 personService.add（newPerson）; 
 newPerson = new Person（）; 
 
返回index; 
} 
} 
  

最后，我想成为能够在REST资源类和JSF bean中使用相同的应用程序作用域服务实例，但我无法让CDI和JAX-RS协同工作。

JSF / CDI部分工作正常，但注入REST资源类并不真正起作用。我阅读了一些文章，其中他们展示了两种不同的方法来组合CDI和JAX-RS：第一种方法是使用 @ManagedBean 注释REST资源类以便为类由CDI容器实例化并由JAX-RS容器管理：

  @ ManagedBean 
 @Path（/ person）
 public class PersonController 
 {
 @Inject 
 private PersonService personService; 
 ... 
  

第二种方法是给班级一个CDI范围，例如： @RequestScoped ，以便由CDI容器实例化和管理类。

  @Path（/ person）
 @RequestScoped 
 public class PersonController 
 {
 @Inject 
 private PersonService personService ; 
 ... 
  

这些方法都不适合我。我总是遇到以下异常：

  org.glassfish.hk2.api.UnsatisfiedDependencyException：在Injectee中没有可用于注射的对象（r​​equiredType = PersonService，parent = PersonController，qualifiers = {}），position = -1，optional = false，self = false，unqualified = null，5643079）
 at org。 jvnet.hk2.internal.ThreeThirtyResolver.resolve（ThreeThirtyResolver.java:74）
 at org.jvnet.hk2.internal.ClazzCreator.resolve(ClazzCreator.java:208）
 at org.jvnet.hk2。 internal.ClazzCreator.resolveAllDependencies（ClazzCreator.java:231）
 at org.jvnet.hk2.internal.ClazzCreator.create(ClazzCreator.java:328) 
 at org.jvnet.hk2.internal.SystemDescriptor。创建（SystemDescriptor.java:454）
 org.glassfish.jersey.process.internal.RequestScope.findOrCreate（RequestScope.java:158）
 at org.jvnet.hk2.internal.Utilities.createService（ Utilities.java:2296）
 at org.jvnet.hk2.internal.Servic eLocatorImpl.getService（ServiceLocatorImpl.java:590）
 at org.jvnet.hk2.internal.ServiceLocatorImpl.getService(ServiceLocatorImpl.java:577）
 at org.glassfish.jersey.internal.inject.Injections。 getOrCreate（Injections.java:172）
  

但是当将注入绑定配置更改为时，此错误消失： / p>

  bind（PersonServiceImpl.class）.to（PersonService.class）; 
  

现在注入有些工作，但对于每个REST请求，我得到<$ c $的新实例c> PersonServiceImpl 注入，即使此服务是应用程序作用域。对我来说，这是一个指标，JAX-RS组件与CDI完全分离，并且与CDI / JSF一样存在于完全不同的环境或容器中。

<那么我真的很想知道如何让这两个概念在纯servlet 3.0容器中协同工作。

解决方案

我解决了我的问题。

问题是，Jersey JAX-RS实现使用HK2依赖注入框架，而这个框架根本不知道CDI bean。并按照这篇文章，我让CDI bean可用于HK2注入绑定，并且注入我的应用程序范围的bean现在工作正常。

但我真的很想知道为什么将Java EE的两个组成部分组合在一起这么麻烦。

更新：作为G. Demecki在评论中提到，这是解决方案不再需要！但在提出这个问题时它帮助了我。

I have a web application running on a Servlet 3.0 container (Jetty 9.0.4) using JSF 2.2 (Mojorra 2.1.3) & CDI 1.1 (Weld 2.0.3). No full-fledged application server is used. In this application I also have a JAX-RS 2.0 (Jersey 2.2) resource class serving REST requests. I have integrated JAXB binding and also JSON marshalling (Jackson 2.2). I use Maven 3.0.5 for the build management. These are the relevant parts of my project setup:

Maven pom.xml:

...
<dependencies>

    <!-- Servlet 3.0 API -->
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.1.0</version>
        <scope>provided</scope>
    </dependency>

    <!-- Contexts and Dependency Injection for Java EE -->
    <dependency>
        <groupId>org.jboss.weld.servlet</groupId>
        <artifactId>weld-servlet</artifactId>
        <version>2.0.3.Final</version>
    </dependency>

    <!-- JavaServer Faces -->
    <dependency>
        <groupId>com.sun.faces</groupId>
        <artifactId>jsf-api</artifactId>
        <version>2.2.2</version>
    </dependency>
    <dependency>
        <groupId>com.sun.faces</groupId>
        <artifactId>jsf-impl</artifactId>
        <version>2.2.2</version>
    </dependency>

    <!-- JAX-RS RESTful Web Services -->
    <dependency>
        <groupId>org.glassfish.jersey.containers</groupId>
        <artifactId>jersey-container-servlet</artifactId>
        <version>2.2</version>
    </dependency>

    <!-- JSON Mapping Framework -->
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>2.2.2</version>
    </dependency>
    <dependency>
        <groupId>org.glassfish.jersey.media</groupId>
        <artifactId>jersey-media-json-jackson</artifactId>
        <version>2.2</version>
    </dependency>
</dependencies>
...

Deployment Descriptor web.xml:

...
<context-param>
    <param-name>javax.faces.PROJECT_STAGE</param-name>
    <param-value>Development</param-value>
</context-param>

<servlet>
    <servlet-name>Faces Servlet</servlet-name>
    <servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
</servlet>

<servlet-mapping>
    <servlet-name>Faces Servlet</servlet-name>
    <url-pattern>/jsf/*</url-pattern>
</servlet-mapping>

<servlet>
    <servlet-name>Jersey REST Service</servlet-name>
    <servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
    <init-param>
        <param-name>javax.ws.rs.Application</param-name>
        <param-value>my.package.config.RestApplication</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
</servlet>

<servlet-mapping>
    <servlet-name>Jersey REST Service</servlet-name>
    <url-pattern>/rest/*</url-pattern>
</servlet-mapping>  

<session-config>
    <session-timeout>30</session-timeout>
</session-config>

<listener>
    <listener-class>org.jboss.weld.environment.servlet.Listener</listener-class>
</listener>

<listener>
    <listener-class>com.sun.faces.config.ConfigureListener</listener-class>
</listener>

<resource-env-ref>
    <description>Object factory for the CDI Bean Manager</description>
    <resource-env-ref-name>BeanManager</resource-env-ref-name>
    <resource-env-ref-type>javax.enterprise.inject.spi.BeanManager</resource-env-ref-type>
</resource-env-ref>
...

JAX-RS root resource class:

@Path("/person")
public class PersonController
{
    @Inject
    private PersonService personService;

    @GET
    @Produces({MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML})
    public List<Person> getAllPersons()
    {
        return personService.getAll();
    }

    @GET
    @Path("/{index}")
    @Produces({MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML})
    public Person getPerson(@PathParam("index") int index)
    {
        return personService.get(index);
    }

    @POST
    @Consumes({MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML})
    public void savePerson(Person person)
    {
        personService.add(person);
    }
}

JAX-RS application configuration:

public class RestApplication extends ResourceConfig
{
    public RestApplication()
    {
        // For JSON binding
        register(new JacksonFeature());
        register(new ApplicationBinder());
        packages("my.package.controller");
    }
}

JAX-RS injection binding configuration:

public class ApplicationBinder extends AbstractBinder
{
    @Override
    protected void configure()
    {
        // Means something like: bind the field at an injection point of type PersonService to an instance of type PersonService
        bind(PersonService.class).to(PersonService.class);
    }
}

And finally the JSF managed bean:

@Named
@SessionScoped
public class PersonBean implements Serializable
{
    private static final long serialVersionUID = 1L;

    @Inject
    private PersonService personService;

    private Person newPerson = new Person();

    public List<Person> getAll()
    {
        return personService.getAll();
    }

    public Person getNewPerson()
    {
        return newPerson;
    }

    public void setNewPerson(Person newPerson)
    {
        this.newPerson = newPerson;
    }

    public Gender[] getGenders()
    {
        return Gender.values();
    }

    public String saveNewPerson()
    {
        personService.add(newPerson);
        newPerson = new Person();

        return "index";
    }
}

At the end, I want to be able to use the same application scoped service instances in the REST resource classes as well as in the JSF beans, but I can't get CDI and JAX-RS work together.

The JSF/CDI part works fine, but the injection into the REST resource classes does not really work. I read some articles, where they showed two different approaches to combine CDI and JAX-RS: The first one is to annotate the REST resource class with @ManagedBean in order for the class to be instantiated by the CDI container and to be managed by the JAX-RS container:

@ManagedBean
@Path("/person")
public class PersonController
{
    @Inject
    private PersonService personService;
    ...

The second approach is to give the class a CDI scope, e.g. @RequestScoped in order for the class to be instantiated and managed by the CDI container.

@Path("/person")
@RequestScoped
public class PersonController
{
    @Inject
    private PersonService personService;
    ...

None of the approaches work for me. I always end up with the following exception:

org.glassfish.hk2.api.UnsatisfiedDependencyException: There was no object available for injection at Injectee(requiredType=PersonService,parent=PersonController,qualifiers={}),position=-1,optional=false,self=false,unqualified=null,5643079)
    at org.jvnet.hk2.internal.ThreeThirtyResolver.resolve(ThreeThirtyResolver.java:74)
    at org.jvnet.hk2.internal.ClazzCreator.resolve(ClazzCreator.java:208)
    at org.jvnet.hk2.internal.ClazzCreator.resolveAllDependencies(ClazzCreator.java:231)
    at org.jvnet.hk2.internal.ClazzCreator.create(ClazzCreator.java:328)
    at org.jvnet.hk2.internal.SystemDescriptor.create(SystemDescriptor.java:454)
    at org.glassfish.jersey.process.internal.RequestScope.findOrCreate(RequestScope.java:158)
    at org.jvnet.hk2.internal.Utilities.createService(Utilities.java:2296)
    at org.jvnet.hk2.internal.ServiceLocatorImpl.getService(ServiceLocatorImpl.java:590)
    at org.jvnet.hk2.internal.ServiceLocatorImpl.getService(ServiceLocatorImpl.java:577)
    at org.glassfish.jersey.internal.inject.Injections.getOrCreate(Injections.java:172)

But this error disappears when changing the injection binding configuration to:

bind(PersonServiceImpl.class).to(PersonService.class);

Now injection somehow works, but for every REST request I get a new instance of the PersonServiceImpl injected, even if this service is application scoped. To me this is an indicator, that the JAX-RS component is totally separated from the CDI stuff and lives in a completely different environment or container as the CDI / JSF stuff does.

So I really wonder how to make these two concepts work together in a pure servlet 3.0 container.

解决方案

I solved my problem.

The problem is, that Jersey JAX-RS implementation uses the HK2 dependency injection framework and this framework is simply not aware of the CDI beans. And by following the idea of the accepted answer in this post, I make the CDI beans available for the HK2 injection bindings and the injection of my application scoped beans works fine now.

But I really wonder why it is so cumbersome to bring together two constituent parts of Java EE.

Update: As G. Demecki mentioned in a comment, this is solution is no longer needed! But it helped me out at the time of asking this question.

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