【发布时间】：2015-05-22 18:43:50
【问题描述】：
我是 EJB 新手，目前正在编写一些简单的 EJB (EJB 3.0)。
这就是我正在尝试的 -->
远程客户端 -> 调用 EJB（远程）（并且此 EJB 调用本地 EJB）。
EJB 1：
界面
package com.vipin.server.local.bean;
import javax.ejb.Local;
@Local
public interface UtilLocalBeanLocal {
public String addString();
}
实现此接口的类：
package com.vipin.server.local.bean;
import javax.ejb.Local;
import javax.ejb.Stateless;
@Stateless(mappedName="UtilLocalBeanMappedName")
@Local(value=UtilLocalBeanLocal.class)
public class UtilLocalBean implements UtilLocalBeanLocal {
public UtilLocalBean() {
}
@Override
public String addString() {
return "Added from Local bean";
}
}
所以，我正在创建的这个 EJB 被另一个 EJB “本地”使用。
EJB 2：
界面
package com.vipin.bean.session;
import javax.ejb.Remote;
@Remote
public interface FirstBeanRemote {
public String callMe();
}
实现此接口的类。
package com.vipin.bean.session;
import javax.ejb.EJB;
import javax.ejb.Remote;
import javax.ejb.Stateless;
import com.vipin.server.local.bean.UtilLocalBeanLocal;
@Stateless(mappedName="FirstBeanMappedName")
@Remote(value=FirstBeanRemote.class)
public class FirstBean implements FirstBeanRemote {
@EJB(name="UtilLocalBeanMappedName")
private UtilLocalBeanLocal utilLocalBeanLocal;
/*@EJB(name="UtilLocalBeanMappedName")
private UtilLocalBean utilLocalBean;*/
public FirstBean() {
}
@Override
public String callMe() {
return "Hi there!" + utilLocalBeanLocal.addString();
}
}
我创建了一个远程客户端，它将调用 EJB -> FirstBean，这个 EJB 将在内部调用 UtilLocalBean（注入 @EJB 注释），如下代码 sn-p：
@EJB(name="UtilLocalBeanMappedName")
private UtilLocalBeanLocal utilLocalBeanLocal;
在这里，我使用了注入 EJB 实例的“接口”。而且效果很好。
当我这样使用时问题就开始了：
@EJB(name="UtilLocalBeanMappedName")
private UtilLocalBean utilLocalBean;
--> 我使用的是类名本身，而不是接口。
在这种情况下，当我启动 JBOSS AS (7.1.1 final) 时，它会抛出异常：
00:07:33,104 ERROR [org.jboss.msc.service.fail] (MSC service thread 1-6) MSC00001: Failed to start service jboss.deployment.subunit."EJB30TestProjEAR.ear"."EJB30TestProj.jar".INSTALL: org.jboss.msc.service.StartException in service jboss.deployment.subunit."EJB30TestProjEAR.ear"."EJB30TestProj.jar".INSTALL: Failed to process phase INSTALL of subdeployment "EJB30TestProj.jar" of deployment "EJB30TestProjEAR.ear"
...
Caused by: org.jboss.as.server.deployment.DeploymentUnitProcessingException: JBAS014544: No EJB found with interface of type 'com.vipin.server.local.bean.UtilLocalBean' for binding UtilLocalBeanMappedName
...
00:07:33,421 ERROR [org.jboss.as.server.deployment.scanner] (DeploymentScanner-threads - 1) {"JBAS014653: Composite operation failed and was rolled back. Steps that failed:" => {"Operation step-2" => {"JBAS014671: Failed services" => {"jboss.deployment.subunit.\"EJB30TestProjEAR.ear\".\"EJB30TestProj.jar\".INSTALL" => "org.jboss.msc.service.StartException in service jboss.deployment.subunit.\"EJB30TestProjEAR.ear\".\"EJB30TestProj.jar\".INSTALL: Failed to process phase INSTALL of subdeployment \"EJB30TestProj.jar\" of deployment \"EJB30TestProjEAR.ear\""},"JBAS014771: Services with missing/unavailable dependencies" => ["jboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.FirstBean.ValidatorFactoryjboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.FirstBeanMissing[jboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.FirstBean.ValidatorFactoryjboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.FirstBean]","jboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.FirstBean.Validatorjboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.FirstBeanMissing[jboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.FirstBean.Validatorjboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.FirstBean]","jboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.UtilLocalBean.Validatorjboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.UtilLocalBeanMissing[jboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.UtilLocalBean.Validatorjboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.UtilLocalBean]","jboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.UtilLocalBean.ValidatorFactoryjboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.UtilLocalBeanMissing[jboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.UtilLocalBean.ValidatorFactoryjboss.naming.context.java.comp.EJB30TestProjEAR.EJB30TestProj.UtilLocalBean]"]}}}
@EJB 仅应用于接口时是否有效？任何意见都非常感谢。
【问题讨论】：