java - Primefaces:ImageCropper-发生转换错误-croppedImage为null

首先，我正在使用

Mojarra 2.0.4
Glassfish v.3.0.1
Primeface primefaces-2.2-1.jar

因此，我有一个简单的页面，它将尝试裁剪图像，当我尝试单击commandButton调用裁剪操作时，在更新我的Conversion Error Occur消息时得到了growl。这是我的代码

<p:growl id="msgs" showDetail="true"/>
<h:form>
  <table cellspacing="10">
     <tr>
         <td>
             <p:imageCropper value="#{CropImage.croppedImage}" image="#{CropImage.me.profilePic}"
                                initialCoords="225,75,500" aspectRatio="1.25" />
         </td>
         <td style="vertical-align: top;">
             <h:outputText value="My Thumb Nail" styleClass="labelText"/><br/>
             <p:graphicImage value="#{CropImage.imageName}" styleClass="icon"/><br/><br/>
             <p:commandButton value="Crop" actionListener="#{CropImage.crop}" update="msgs"/>
         </td>
     </tr>
  </table>
</h:form>

这是我的豆子

@ManagedBean(name="CropImage")
@ViewScoped
public class CropImage {

@ManagedProperty(value="#{SessionBean}")
private SessionBean sessionBean;

private User me;

private CroppedImage croppedImage;

private String imageName;

private String ext;

private static final Logger logger = Logger.getLogger(CropImage.class.getName());

public CropImage() {
}

@PostConstruct
public void init(){
    me = sessionBean.getMe();
    imageName = me.getProfilePic();
    //obtain the extension
    ext = imageName.substring(imageName.lastIndexOf("."), imageName.length());
}

public String getImageName() {
    return imageName;
}

public void setImageName(String imageName) {
    this.imageName = imageName;
}

public SessionBean getSessionBean() {
    return sessionBean;
}

public void setSessionBean(SessionBean sessionBean) {
    this.sessionBean = sessionBean;
}

public User getMe() {
    return me;
}

public void setMe(User me) {
    this.me = me;
}

public CroppedImage getCroppedImage() {
    return croppedImage;
}

public void setCroppedImage(CroppedImage croppedImage) {
    this.croppedImage = croppedImage;
}

public String crop(){
    ServletContext servletContext = (ServletContext) FacesContext.getCurrentInstance().getExternalContext().getContext();
    UUID uuid = UUID.randomUUID();
    imageName = servletContext.getInitParameter("resources") + File.separator;
    imageName += "cropped" + File.separator + uuid.toString() + ext;
    FileImageOutputStream imageOutput;
    try {
        imageOutput = new FileImageOutputStream(new File(imageName));
        imageOutput.write(croppedImage.getBytes(), 0, croppedImage.getBytes().length);
        imageOutput.close();
    } catch (FileNotFoundException e) {
        logger.log(Level.SEVERE, e.getMessage());
    } catch (IOException e) {
        logger.log(Level.SEVERE, e.getMessage());
    }
    return null;
}
}

最佳答案

您要裁剪的图像是否显示？

<p:imageCropper>的图像属性必须是图像的相对路径。

从PrimeFaces文档中：


  对于本地图像，始终使用ImageCropper
  要求图像路径是上下文
  相对的。所以简单地做到这一点
  只需添加斜杠（“ /path/to/image.png”）
  然后imagecropper会在
  ％WEBAPP_ROOT％/ path / to / image.png。
  操作网址相对本地图像是
  不支持。