java无法正确使用(@Inject)
当我尝试使用@Inject来注入我的DAO类时,在一个管理器中,为了使它能够将gson文件提供给当前地址,当我转到特定的web地址时,会出现这个异常。谁能给我解释一下是什么问题吗。我认为问题可能来自@Inject,它不能正常工作,但我不确定
java.lang.RuntimeException: org.apache.cxf.interceptor.Fault: Cannot obtain a free instance.; nested exception is:
javax.enterprise.inject.UnsatisfiedResolutionException: Api type [cinema.dao.ProjectionDAO] is not found with the qualifiers
Qualifiers: [@javax.enterprise.inject.Default()]
for injection into Field Injection Point, field name : projectionDAO, Bean Owner : [ProjectionManager, Name:null, WebBeans Type:DEPENDENT, API Types:[cinema.services.ProjectionManager,java.lang.Object], Qualifiers:[javax.enterprise.inject.Any,javax.enterprise.inject.Default]] while invoking public java.util.Collection cinema.services.ProjectionManager.getAllProjections() with params [].
org.apache.cxf.interceptor.AbstractFaultChainInitiatorObserver.onMessage(AbstractFaultChainInitiatorObserver.java:116)
org.apache.cxf.phase.PhaseInterceptorChain.doIntercept(PhaseInterceptorChain.java:324)
org.apache.cxf.transport.ChainInitiationObserver.onMessage(ChainInitiationObserver.java:121)
org.apache.cxf.transport.http.AbstractHTTPDestination.invoke(AbstractHTTPDestination.java:240)
org.apache.openejb.server.cxf.rs.CxfRsHttpListener.onMessage(CxfRsHttpListener.java:187)
org.apache.openejb.server.rest.RsServlet.service(RsServlet.java:53)
javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
经理代码:
package cinema.services;
import java.util.Collection;
import javax.ejb.Stateless;
import javax.inject.Inject;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import cinema.dao.ProjectionDAO;
import cinema.model.Projection;
@Stateless
@Path("projection")
public class ProjectionManager {
@Inject
private ProjectionDAO projectionDAO;
@GET
@Produces("application/json")
public Collection<Projection> getAllProjections(){
return projectionDAO.getAllProjections();
}
}
以下是项目DAO:
package cinema.dao;
import java.util.Collection;
import javax.inject.Singleton;
import javax.persistence.EntityManager;
import javax.persistence.NoResultException;
import javax.persistence.PersistenceContext;
import cinema.model.Projection;
import cinema.model.User;
@Singleton
public class ProjectionDAO {
@PersistenceContext
private EntityManager em;
public Collection<Projection> getAllProjections(){
return em.createNamedQuery("getAllProjections", Projection.class).getResultList();
}
public void addProjection(Projection projection){
em.persist(projection);
}
public Projection findProjectionByMovieTitle(String movieTitle){
try {
return em.createNamedQuery("getProjectionByMovieTitle", Projection.class)
.setParameter("movieTitle", movieTitle).getSingleResult();
} catch (NoResultException e){
return null;
}
}
public void buyTicket(Projection projection, User user){
Projection foundProjection = findProjectionByMovieTitle(projection.getMovieTitle());
if(foundProjection != null){
user.getCurrentProjections().add(projection);
int newFreeSpaces = foundProjection.getFreeSpaces() - 1;
foundProjection.setFreeSpaces(newFreeSpaces);
}
}
}
投影是一个简单的模型,它给出电影院中不同投影的电影名称和开始时间
# 1 楼答案
你的问题没有说明重要的信息,比如正在使用的版本,或者你是如何部署的,所以我要大胆尝试一下
beans.xml
文件。但我不确定你是在部署WAR还是JAR文件李>beans.xml
文件,尝试用@ApplicationScope
替换@Singleton
。这将更准确地发现你的类李>