2

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{
    private PhotographId id;

    @ManyToOne(fetch = FetchType.EAGER)
    @JoinColumn(name = "diagnostic_id", nullable = false, insertable = false, updatable = false)
    private Diagnostic diagnostic;

    @Column(name = "photograph_content_type")
    private String photographContentType;

    @EmbeddedId
    @AttributeOverrides({
        @AttributeOverride(name = "diagnosticId", column = @Column(name  = "diagnostic_id", nullable = false)),
        @AttributeOverride(name = "photo", column = @Column(name = "photo", nullable = false)),
        @AttributeOverride(name = "photographDescription", column = @Column(name = "photograph_description", nullable = false, length = 100)) })
    public PhotographId getId() {
       return this.id;
    }

//Getters and Setters...
}

这是pk 的可嵌入类：

@Embeddable
public class PhotographId{
    @Column(name = "diagnostic_id", nullable = false)
    private Long diagnosticId;
    @Column(name = "photo", nullable = false)
    private byte[] photo;
    @Column(name = "photograph_description", nullable = false, length = 100)
    private String photographDescription;

//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.id)}"
                        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(PhotographId id) {
    try {
        return photographService.getContent(id);
    } catch (ServiceException e) {
        FacesMessage mensaje = new FacesMessage(
                FacesMessage.SEVERITY_ERROR,
                "Error al buscar la fotografía "
                        + id.getPhotographDescription(), 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.getId().getPhoto());
        ExternalContext ec = FacesContext.getCurrentInstance()
                .getExternalContext();
        ec.getSessionMap()
                .put(photograph.getId().toString(),
                        imageContent);
    }
}
// Getters and setters....
}

当我使用 maven 时，我的应用程序目录如下：

src
|----main
     |----webapp
          |----images

我的 server.log 中有错误，我在页面中看不到图像，我的代码中缺少什么？

20:22:43,687 ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[default-host].[/patientdiagnostics].[Faces Servlet]] (http-localhost/127.0.0.1:8080-1) JBWEB000236: Servlet.service() for servlet Faces Servlet threw exception: java.lang.IllegalArgumentException: argument type mismatch
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_79]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_79]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_79]
at java.lang.reflect.Method.invoke(Method.java:606) [rt.jar:1.7.0_79]
at org.omnifaces.resourcehandler.GraphicResource.getInputStream(GraphicResource.java:241) [omnifaces-2.0.jar:2.0]
at com.sun.faces.application.resource.ResourceHandlerImpl.handleResourceRequest(ResourceHandlerImpl.java:260) [jsf-impl-2.1.28.redhat-3.jar:2.1.28.redhat-3]
at javax.faces.application.ResourceHandlerWrapper.handleResourceRequest(ResourceHandlerWrapper.java:125) [jboss-jsf-api_2.1_spec-2.1.28.Final-redhat-1.jar:2.1.28.Final-redhat-1]
at org.primefaces.application.resource.PrimeResourceHandler.handleResourceRequest(PrimeResourceHandler.java:74) [primefaces-5.1.jar:5.1]
at javax.faces.application.ResourceHandlerWrapper.handleResourceRequest(ResourceHandlerWrapper.java:125) [jboss-jsf-api_2.1_spec-2.1.28.Final-redhat-1.jar:2.1.28.Final-redhat-1]
at javax.faces.application.ResourceHandlerWrapper.handleResourceRequest(ResourceHandlerWrapper.java:125) [jboss-jsf-api_2.1_spec-2.1.28.Final-redhat-1.jar:2.1.28.Final-redhat-1]
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:591) [jboss-jsf-api_2.1_spec-2.1.28.Final-redhat-1.jar:2.1.28.Final-redhat-1]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:295) [jbossweb-7.4.8.Final-redhat-4.jar:7.4.8.Final-redhat-4]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214) [jbossweb-7.4.8.Final-redhat-4.jar:7.4.8.Final-redhat-4]
at org.primefaces.webapp.filter.FileUploadFilter.doFilter(FileUploadFilter.java:105) [primefaces-5.1.jar:5.1]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:246) [jbossweb-7.4.8.Final-redhat-4.jar:7.4.8.Final-redhat-4]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214) [jbossweb-7.4.8.Final-redhat-4.jar:7.4.8.Final-redhat-4]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:231) [jbossweb-7.4.8.Final-redhat-4.jar:7.4.8.Final-redhat-4]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:149) [jbossweb-7.4.8.Final-redhat-4.jar:7.4.8.Final-redhat-4]
at org.jboss.as.jpa.interceptor.WebNonTxEmCloserValve.invoke(WebNonTxEmCloserValve.java:50) [jboss-as-jpa-7.4.0.Final-redhat-19.jar:7.4.0.Final-redhat-19]
at org.jboss.as.jpa.interceptor.WebNonTxEmCloserValve.invoke(WebNonTxEmCloserValve.java:50) [jboss-as-jpa-7.4.0.Final-redhat-19.jar:7.4.0.Final-redhat-19]
at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:169) [jboss-as-web-7.4.0.Final-redhat-19.jar:7.4.0.Final-redhat-19]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:145) [jbossweb-7.4.8.Final-redhat-4.jar:7.4.8.Final-redhat-4]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:97) [jbossweb-7.4.8.Final-redhat-4.jar:7.4.8.Final-redhat-4]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:102) [jbossweb-7.4.8.Final-redhat-4.jar:7.4.8.Final-redhat-4]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:344) [jbossweb-7.4.8.Final-redhat-4.jar:7.4.8.Final-redhat-4]
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:856) [jbossweb-7.4.8.Final-redhat-4.jar:7.4.8.Final-redhat-4]
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:653) [jbossweb-7.4.8.Final-redhat-4.jar:7.4.8.Final-redhat-4]
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:926) [jbossweb-7.4.8.Final-redhat-4.jar:7.4.8.Final-redhat-4]
at java.lang.Thread.run(Thread.java:745) [rt.jar:1.7.0_79]

我还尝试了类似于Display database blob images in <p:graphicImage> inside <ui:repeat>

4

1 回答 1

0

如其文档和展示中所述，

如果属性是带参数的方法表达式，则每个参数都将转换为字符串 HTTP 请求参数，并使用类注册的转换器转换回实际对象，这些转换器可通过Application.createConverter(Class). 因此，大多数标准类型Long已经被隐式支持。如果您出于某种原因需要提供自定义对象作为参数，则需要通过@FacesConverter(forClass).

将<o:graphicImage>使用为参数类型的类注册的 JSF 转换器将所有 EL 方法参数转换为字符串并返回。JSF 已经为 eg Longtype 内置了转换器，所以这就是他们开箱即用的原因。但是您有一个PhotographId类型作为 EL 方法参数，显然没有为此注册 JSF 转换器。

你有 2 个选择：

  1. 不要提供整个实体作为参数。请改用其标识符，在您的情况下只是Long.

    例如

    <o:graphicImage value="#{imageStreamer.getById(image.id.diagnosticId)}">

    并相应地改变getById()方法。

  2. 为该类创建一个 JSF 转换器PhotographId。

    @FacesConverter(forClass=PhotographId.class)
public class PhotographIdConverter implements Converter {

    @Override
    public String getAsString(FacesContext context, UIComponent component, Object modelValue) {
        // Write code here which converts PhotographId to its unique String representation.
    }

    @Override
    public Object getAsObject(FacesContext context, UIComponent component, String submittedValue) {
        // Write code here which coverts the PhotographId's unique String representation as created in above method back to the original PhotographId object.
    }

}

也就是说，模型看起来很奇怪。照片的内容是复合键的一部分..?? 这在 SQL 和 Java 方面都非常低效。您不妨对其进行审查和修复（然后您需要<o:graphicImage>相应地更改用法）。

此外，由于图像请求不代表 JSF 页面，因此您尝试在流媒体的 catch 块中添加的面孔消息不会显示在任何地方。你最好只记录/邮寄它。

于 2015-05-03T07:00:39.450 回答