> > Why does GAE do so? Scalability, Resource Utilization and Security. GAE is a hosted service that google provides. One of the ways in which they scale is preventing writes to the file system. Because you don't write to the file system, if a machine goes down your application doesn't lose anything. Preventing threads is more of a CPU utilization concern, I think. By restricting you to http request/response, they can ensure you don't use more than a given threshold of CPU. And finally, preventing sockets is a security concern. You don't want to allow arbitrary running code to open socket connections ..
None of this is related to GWT ofcourse. You can use GWT with any backend technology you want. Its unfortunate that GAE is enabled by default though. --Sri P.S. BTW, did that fix your problem? On 12 May 2010 23:15, Carfield Yim <carfi...@gmail.com> wrote: > Interesting, why GAE do so? My application opening a file, basically > it is just a better looking webserver. However, it doesn't look like > inheritance from servlet security restriction... > > Is there more document mention why GAE do that? > > On May 12, 2:14 am, Sripathi Krishnan <sripathi.krish...@gmail.com> > wrote: > > I am guessing the class hk/com/carfield/core/Context is performing a > > restricted operation - like creating a thread or opening a file/socket > > connection. GAE does not allow you to perform such operations, and when > you > > do - it fails with a stack trace similar to what you have pasted. > > > > Disable GAE in your eclipse settings, and completely remove all GAE jar > > files from your classpath. That should solve the problem. > > > > --Sri > > > > On 11 May 2010 22:48, Carfield Yim <carfi...@gmail.com> wrote: > > > > > HI, I just use the class in another JAR, eclipse show no compilation > > > error, and GWT compilation is success, why I still get following > > > error? BTW, I start the application using eclipse GWT plugin. > > > > > May 11, 2010 5:17:36 PM com.google.apphosting.utils.jetty.JettyLogger > > > warn > > > WARNING: Nested in javax.servlet.ServletException: init: > > > java.lang.NoClassDefFoundError: hk/com/carfield/core/Context > > > at > > > > > > hk.com.carfield.server.InternetfolderServiceImpl.<init>(InternetfolderServi > ceImpl.java: > > > 27) > > > at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native > > > Method) > > > at > > > > > > sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAcce > ssorImpl.java: > > > 57) > > > at > > > > > > sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstru > ctorAccessorImpl.java: > > > 45) > > > at > java.lang.reflect.Constructor.newInstance(Constructor.java:532) > > > at java.lang.Class.newInstance0(Class.java:372) > > > at java.lang.Class.newInstance(Class.java:325) > > > at org.mortbay.jetty.servlet.Holder.newInstance(Holder.java:153) > > > at > > > org.mortbay.jetty.servlet.ServletHolder.getServlet(ServletHolder.java: > > > 339) > > > at > > > org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java: > > > 463) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1093) > > > at > > > > > > com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFi > lter.java: > > > 51) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1084) > > > at > > > > > > com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(Trans > actionCleanupFilter.java: > > > 43) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1084) > > > at > > > > > > com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFile > Filter.java: > > > 121) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1084) > > > at > > > org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java: > > > 360) > > > at > > > org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java: > > > 216) > > > at > > > org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java: > > > 181) > > > at > > > org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java: > > > 712) > > > at > org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java: > > > 405) > > > at > > > > > > com.google.apphosting.utils.jetty.DevAppEngineWebAppContext.handle(DevAppEn > gineWebAppContext.java: > > > 70) > > > at > > > org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java: > > > 139) > > > at com.google.appengine.tools.development.JettyContainerService > > > $ApiProxyHandler.handle(JettyContainerService.java:352) > > > at > > > org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java: > > > 139) > > > at org.mortbay.jetty.Server.handle(Server.java:313) > > > at > > > org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java: > > > 506) > > > at org.mortbay.jetty.HttpConnection > > > $RequestHandler.content(HttpConnection.java:844) > > > at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:644) > > > at > org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:211) > > > at > org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:381) > > > at > > > > org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java: > > > 396) > > > at org.mortbay.thread.BoundedThreadPool > > > $PoolThread.run(BoundedThreadPool.java:442) > > > Caused by: java.lang.ClassNotFoundException: > > > hk.com.carfield.core.Context > > > at java.net.URLClassLoader$1.run(URLClassLoader.java:217) > > > at java.security.AccessController.doPrivileged(Native Method) > > > at java.net.URLClassLoader.findClass(URLClassLoader.java:205) > > > at java.lang.ClassLoader.loadClass(ClassLoader.java:319) > > > at > > > > > > com.google.appengine.tools.development.IsolatedAppClassLoader.loadClass(Iso > latedAppClassLoader.java: > > > 151) > > > at java.lang.ClassLoader.loadClass(ClassLoader.java:264) > > > at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:332) > > > ... 34 more > > > May 11, 2010 5:17:36 PM com.google.apphosting.utils.jetty.JettyLogger > > > warn > > > WARNING: Nested in javax.servlet.ServletException: init: > > > java.lang.NoClassDefFoundError: hk/com/carfield/core/Context > > > at > > > > > > hk.com.carfield.server.InternetfolderServiceImpl.<init>(InternetfolderServi > ceImpl.java: > > > 27) > > > at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native > > > Method) > > > at > > > > > > sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAcce > ssorImpl.java: > > > 57) > > > at > > > > > > sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstru > ctorAccessorImpl.java: > > > 45) > > > at > java.lang.reflect.Constructor.newInstance(Constructor.java:532) > > > at java.lang.Class.newInstance0(Class.java:372) > > > at java.lang.Class.newInstance(Class.java:325) > > > at org.mortbay.jetty.servlet.Holder.newInstance(Holder.java:153) > > > at > > > org.mortbay.jetty.servlet.ServletHolder.getServlet(ServletHolder.java: > > > 339) > > > at > > > org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java: > > > 463) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1093) > > > at > > > > > > com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFi > lter.java: > > > 51) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1084) > > > at > > > > > > com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(Trans > actionCleanupFilter.java: > > > 43) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1084) > > > at > > > > > > com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFile > Filter.java: > > > 121) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1084) > > > at > > > org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java: > > > 360) > > > at > > > org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java: > > > 216) > > > at > > > org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java: > > > 181) > > > at > > > org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java: > > > 712) > > > at > org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java: > > > 405) > > > at > > > > > > com.google.apphosting.utils.jetty.DevAppEngineWebAppContext.handle(DevAppEn > gineWebAppContext.java: > > > 70) > > > at > > > org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java: > > > 139) > > > at com.google.appengine.tools.development.JettyContainerService > > > $ApiProxyHandler.handle(JettyContainerService.java:352) > > > at > > > org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java: > > > 139) > > > at org.mortbay.jetty.Server.handle(Server.java:313) > > > at > > > org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java: > > > 506) > > > at org.mortbay.jetty.HttpConnection > > > $RequestHandler.content(HttpConnection.java:844) > > > at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:644) > > > at > org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:211) > > > at > org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:381) > > > at > > > > org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java: > > > 396) > > > at org.mortbay.thread.BoundedThreadPool > > > $PoolThread.run(BoundedThreadPool.java:442) > > > May 11, 2010 5:17:36 PM com.google.apphosting.utils.jetty.JettyLogger > > > warn > > > WARNING: /gtwinternetfolder/internetfolder > > > java.lang.NoClassDefFoundError: hk/com/carfield/core/Context > > > at > > > > > > hk.com.carfield.server.InternetfolderServiceImpl.<init>(InternetfolderServi > ceImpl.java: > > > 27) > > > at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native > > > Method) > > > at > > > > > > sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAcce > ssorImpl.java: > > > 57) > > > at > > > > > > sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstru > ctorAccessorImpl.java: > > > 45) > > > at > java.lang.reflect.Constructor.newInstance(Constructor.java:532) > > > at java.lang.Class.newInstance0(Class.java:372) > > > at java.lang.Class.newInstance(Class.java:325) > > > at org.mortbay.jetty.servlet.Holder.newInstance(Holder.java:153) > > > at > > > org.mortbay.jetty.servlet.ServletHolder.getServlet(ServletHolder.java: > > > 339) > > > at > > > org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java: > > > 463) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1093) > > > at > > > > > > com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFi > lter.java: > > > 51) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1084) > > > at > > > > > > com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(Trans > actionCleanupFilter.java: > > > 43) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1084) > > > at > > > > > > com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFile > Filter.java: > > > 121) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1084) > > > at > > > org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java: > > > 360) > > > at > > > org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java: > > > 216) > > > at > > > org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java: > > > 181) > > > at > > > org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java: > > > 712) > > > at > org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java: > > > 405) > > > at > > > > > > com.google.apphosting.utils.jetty.DevAppEngineWebAppContext.handle(DevAppEn > gineWebAppContext.java: > > > 70) > > > at > > > org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java: > > > 139) > > > at com.google.appengine.tools.development.JettyContainerService > > > $ApiProxyHandler.handle(JettyContainerService.java:352) > > > at > > > org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java: > > > 139) > > > at org.mortbay.jetty.Server.handle(Server.java:313) > > > at > > > org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java: > > > 506) > > > at org.mortbay.jetty.HttpConnection > > > $RequestHandler.content(HttpConnection.java:844) > > > at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:644) > > > at > org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:211) > > > at > org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:381) > > > at > > > > org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java: > > > 396) > > > at org.mortbay.thread.BoundedThreadPool > > > $PoolThread.run(BoundedThreadPool.java:442) > > > May 11, 2010 5:17:36 PM com.google.apphosting.utils.jetty.JettyLogger > > > warn > > > WARNING: /gtwinternetfolder/internetfolder > > > java.lang.NoClassDefFoundError: hk/com/carfield/core/Context > > > at > > > > > > hk.com.carfield.server.InternetfolderServiceImpl.<init>(InternetfolderServi > ceImpl.java: > > > 27) > > > at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native > > > Method) > > > at > > > > > > sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAcce > ssorImpl.java: > > > 57) > > > at > > > > > > sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstru > ctorAccessorImpl.java: > > > 45) > > > at > java.lang.reflect.Constructor.newInstance(Constructor.java:532) > > > at java.lang.Class.newInstance0(Class.java:372) > > > at java.lang.Class.newInstance(Class.java:325) > > > at org.mortbay.jetty.servlet.Holder.newInstance(Holder.java:153) > > > at > > > org.mortbay.jetty.servlet.ServletHolder.getServlet(ServletHolder.java: > > > 339) > > > at > > > org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java: > > > 463) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1093) > > > at > > > > > > com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFi > lter.java: > > > 51) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1084) > > > at > > > > > > com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(Trans > actionCleanupFilter.java: > > > 43) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1084) > > > at > > > > > > com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFile > Filter.java: > > > 121) > > > at org.mortbay.jetty.servlet.ServletHandler > > > $CachedChain.doFilter(ServletHandler.java:1084) > > > at > > > org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java: > > > 360) > > > at > > > org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java: > > > 216) > > > at > > > org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java: > > > 181) > > > at > > > org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java: > > > 712) > > > at > org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java: > > > 405) > > > at > > > > > > com.google.apphosting.utils.jetty.DevAppEngineWebAppContext.handle(DevAppEn > gineWebAppContext.java: > > > 70) > > > at > > > org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java: > > > 139) > > > at com.google.appengine.tools.development.JettyContainerService > > > $ApiProxyHandler.handle(JettyContainerService.java:352) > > > at > > > org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java: > > > 139) > > > at org.mortbay.jetty.Server.handle(Server.java:313) > > > at > > > org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java: > > > 506) > > > at org.mortbay.jetty.HttpConnection > > > $RequestHandler.content(HttpConnection.java:844) > > > at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:644) > > > at > org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:211) > > > at > org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:381) > > > at > > > > org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java: > > > 396) > > > at org.mortbay.thread.BoundedThreadPool > > > $PoolThread.run(BoundedThreadPool.java:442) > > > Caused by: java.lang.ClassNotFoundException: > > > hk.com.carfield.core.Context > > > at java.net.URLClassLoader$1.run(URLClassLoader.java:217) > > > at java.security.AccessController.doPrivileged(Native Method) > > > at java.net.URLClassLoader.findClass(URLClassLoader.java:205) > > > at java.lang.ClassLoader.loadClass(ClassLoader.java:319) > > > at > > > > > > com.google.appengine.tools.development.IsolatedAppClassLoader.loadClass(Iso > latedAppClassLoader.java: > > > 151) > > > at java.lang.ClassLoader.loadClass(ClassLoader.java:264) > > > at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:332) > > > ... 34 more > > > > > -- > > > You received this message because you are subscribed to the Google > Groups > > > "Google Web Toolkit" group. > > > To post to this group, send email to > google-web-tool...@googlegroups.com. > > > To unsubscribe from this group, send email to > > > 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