http://AAA.BBB.CCC.DDD:8080/myapp/ uri的handleURI：'‘返回不明确的结果(Vaadin6)

Question

在我的Vaadin 6应用程序中，我有时会得到以下错误：

SEVERE: Terminal error:
java.lang.RuntimeException: handleURI for http://AAA.BBB.CCC.DDD:8080/myapp/ uri: '' returns ambigious result.
at com.vaadin.ui.Window.handleURI(Window.java:432)
at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.handleURI(AbstractCommunicationManager.java:2291)
at com.vaadin.terminal.gwt.server.CommunicationManager.handleURI(CommunicationManager.java:370)
at com.vaadin.terminal.gwt.server.AbstractApplicationServlet.handleURI(AbstractApplicationServlet.java:1099)
at com.vaadin.terminal.gwt.server.AbstractApplicationServlet.service(AbstractApplicationServlet.java:535)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)

根据Vaadin source的说法，它发生在以下方法中：

public DownloadStream handleURI(URL context, String relativeUri) {

    DownloadStream result = null;
    if (uriHandlerList != null) {
        Object[] handlers;
        synchronized (uriHandlerList) {
            handlers = uriHandlerList.toArray();
        }
        for (int i = 0; i < handlers.length; i++) {
            final DownloadStream ds = ((URIHandler) handlers[i]).handleURI(
                    context, relativeUri);
            if (ds != null) {
                if (result != null) {
                    throw new RuntimeException("handleURI for " + context
                            + " uri: '" + relativeUri
                            + "' returns ambigious result.");
                }
                result = ds;
            }
        }
    }
    return result;
}

我实际上在列生成器中创建了一个DownloadStream (为了在表中显示图像)：

public class ImageColumnGenerator implements Table.ColumnGenerator {
    private static final Logger LOGGER = LoggerFactory.getLogger(ImageColumnGenerator.class);

    public final static String IMAGE_FIELD = "image";

    public Object generateCell(final Table aTable, final Object aItemId, final Object aColumnId) {
        if (!IMAGE_FIELD.equals(aColumnId)) {
            return null;
        }
        final BeanItem<UserProductImageBean> beanItem = (BeanItem<UserProductImageBean>)
                aTable.getItem(aItemId);

        final StreamResource streamResource = new StreamResource(new StreamResource.StreamSource() {
            public InputStream getStream() {
                return new ByteArrayInputStream(beanItem.getBean().getImageData());
            }
        },
                beanItem.getBean().getFileName(),
                MyApplication.getInstance());

        LOGGER.debug("imageResource: " + streamResource);
        final Embedded embedded = new Embedded("", streamResource);


        return embedded;
    }
}

beanItem.getBean().getImageData()是一个包含图像数据的字节数组(byte[])，它是我从web服务中获得的。

MyApplication.getInstance()的定义如下：

public class MyApplication extends Application implements ApplicationContext.TransactionListener
{
    private static ThreadLocal<MyApplication> currentApplication =
            new ThreadLocal<MyApplication> ();

    public static MyApplication getInstance()
    {
        return currentApplication.get ();
    }
}

我能做些什么来修复前面提到的(严重)错误？

Answer 1

只要没人接就行。我并不是什么地狱上面的专家，但是-试着找出这个错误出现在哪种urls上，并在将它们提供给DownloadStream之前对它们做些什么