我无法显示数据库中的图像，它们存储为bytea，我将它们映射如下：
@Entity
@Table(name = "photograph", schema = "public")
public class Photograph{
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "photograph_id", unique = true, nullable = false)
private Long id;
@ManyToOne(fetch = FetchType.EAGER)
@JoinColumn(name = "diagnostic_id", nullable = false, insertable = false, updatable = false)
private Diagnostic diagnostic;
@Column(name = "photo", nullable = false)
private byte[] photo;
@Column(name = "photograph_description", nullable = false, length = 100)
private String photographDescription;
@Column(name = "photograph_content_type")
private String photographContentType;
//Getters and Setters...
}
我可以毫无问题地将所有图像存储在数据库中。问题是当我想在p:dataTable中显示它们时：
<p:dataTable id="dataTableLoadedPhotos"
value="#{imageController.photographListUpdate}" var="image">
<p:column headerText="Fotografías cargadas" width="110">
<o:graphicImage value="#{imageStreamer.getById(image.photographId)}"
alt="#{msgs['label.diagnostic.photograph.notFound']}" />
</p:column>
</p:dataTable>
我正在使用基于BalusC 代码的流媒体：ImageServlet ，我尝试使用o:graphicImage没有成功，mi 代码中缺少一些东西：
@ManagedBean
@ApplicationScoped
public class ImageStreamer {
@EJB
private PhotographService photographService;
public byte[] getById(Long id) {
try {
return photographService.getContent(id);
} catch (ServiceException e) {
FacesMessage mensaje = new FacesMessage(
FacesMessage.SEVERITY_ERROR,
"Error al buscar la fotografía ", e.getMessage());
FacesContext.getCurrentInstance().addMessage(null, mensaje);
}
return null;
}
}
我还有一个带有 @RequestScoped 的托管 bean：
@ManagedBean
@RequestScoped
public class ImageController {
@EJB
private PhotographService photographService;
@ManagedProperty(value = "#{diagnosticDataManager}")
private DiagnosticDataManager diagnosticDataManager;
private List<Photograph> photographListUpdate = new ArrayList<Photograph>();
private Photograph selectedPhoto;
/**
*
*/
public ImageController() {
diagnosticDataManager = new DiagnosticDataManager();
}
@PostConstruct
public void init() {
if (diagnosticDataManager.getDiagnostic().getDiagnosticId() != null)
photographListUpdate = photographService
.findPhotosByDiagnostic(diagnosticDataManager
.getDiagnostic());
for (Photograph photograph : photographListUpdate) {
byte[] imageContent = org.apache.commons.codec.binary.Base64
.decodeBase64(photograph.getPhoto());
ExternalContext ec = FacesContext.getCurrentInstance()
.getExternalContext();
ec.getSessionMap()
.put(photograph.getId().toString(),
imageContent);
}
}
// Getters and setters....
}
我在 p:dataTable 中只看到两行对应于没有图像预加载的图像，只显示了 o:graphicImage 的“alt”属性的消息
使用萤火虫我只在每一行看到这个：
<img alt="Imagen no encontrada" src="/patientdiagnostics/javax.faces.resource/ImageStreamer_getById.xhtml?ln=omnifaces.graphic&v=0&p=7">
我还尝试了类似于Display database blob images in <p:graphicImage> inside <ui:repeat>