我在Mac上本地运行SDK时遇到了这种情况。我正在尝试建立在场处理。我创建了一个简单的servlet,除了日志记录之外什么也不做。但是,我在任何连接和断开连接事件上都遇到以下异常(虽然Channels似乎正在工作)...
Mar 14, 2013 8:04:25 PM com.google.apphosting.utils.jetty.JettyLogger warn
WARNING: /_ah/channel/disconnected/: javax.servlet.UnavailableException: java.lang.InstantiationException
Mar 14, 2013 8:04:38 PM com.google.apphosting.utils.jetty.JettyLogger warn
WARNING: /_ah/channel/connected/: javax.servlet.UnavailableException: java.lang.InstantiationException
我已经在web.xml中注册了用于连接和断开通道的servlet ...
<servlet>
<servlet-name>ChannelPresence</servlet-name>
<servlet-class>com.readyposition.gaetestbed.ChannelPresenceServlet
</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ChannelPresence</servlet-name>
<url-pattern>/_ah/channel/connected/</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>ChannelPresence</servlet-name>
<url-pattern>/_ah/channel/disconnected/</url-pattern>
</servlet-mapping>
处理程序(servlet)本身非常基础......
package com.readyposition.gaetestbed;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.appengine.api.channel.ChannelPresence;
import com.google.appengine.api.channel.ChannelService;
import com.google.appengine.api.channel.ChannelServiceFactory;
@SuppressWarnings("serial")
public abstract class ChannelPresenceServlet extends HttpServlet {
final static Logger logger =
LoggerFactory.getLogger(ChannelPresenceServlet.class);
@Override
public void doGet(final HttpServletRequest req,
final HttpServletResponse resp)
throws IOException, ServletException
{
processCommand(req, resp);
}
@Override
public void doPost(final HttpServletRequest req,
final HttpServletResponse resp)
throws IOException, ServletException
{
processCommand(req, resp);
}
public void processCommand(final HttpServletRequest req,
final HttpServletResponse resp)
throws IOException, ServletException
{
final ChannelService channelService =
ChannelServiceFactory.getChannelService();
final ChannelPresence presence = channelService.parsePresence(req);
logger.info("Channel Presence - clientId={}, isConnected={}",
presence.clientId(), presence.isConnected());
}
}
任何帮助都将不胜感激。
答案 0 :(得分:1)
多么尴尬。剪切和粘贴错误。我的servlet类错误地抽象了。叹。固定的。
我看到其他几个人在不同的情况下抱怨同样的例外,至少有一个与频道存在有关。如果另一个人意识到他们错误地将servlet类留作抽象,那么我认为这将是有益的。
感谢任何试图跟踪我的老鼠洞的人。