我只是试图加载任何JSP文件，但无论它是一个空应用程序还是谷歌应用程序引擎提供的演示之一，我都会遇到同样的错误。
我认为这与我的Eclipse设置有关。
任何帮助都将不胜感激。我正要放弃。
HTTP错误500
访问/guestbook.jsp时出现问题。原因：
Unable to load class for JSP
原因：
org.apache.jaster.JasperException：无法为JSP加载类网址：org.apache.jasper.JspCompilationContext.load(JspCompillationContext.java:630)网址：org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletsWrapper.java:144)网址：org.apache.jasper.servlet.JspServletWrapper.service(JspServletsWrapper.java:329)网址：org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)网址：org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)网址：com.google.aappengine.tools.development.PrivilegedJspServlet.access$101(PrivilegedJspServlet.java:23)网址：com.google.aappengine.tools.development.PrivilegedJspServlet$2.run(PrivilegedJspServlet.java:59)位于java.security.AccessController.doPrivileged(本机方法)网址：com.google.aappengine.tools.development.PrivilegedJspServlet.service(PrivilegedJspServlet.java:57)位于javax.servlet.httpHttpServlet.service(HttpServlet.java：717)网址：org.mortbay.japty.servlet.ServletHolder.handle(ServletHolder.java:511)网址：org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(servlet处理程序.java：1166)网址：com.google.aappengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:35)网址：org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)网址：com.google.aappengine.api.blobstore.dev.ServiceBlobFilter.doFilter(ServeBlobFilter.java:58)网址：org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)网址：com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43)网址：org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)网址：com.google.aappengine.tools.development.StaticFileFilter.doFilter(StaticFileFilter.java:122)网址：org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)网址：com.google.aappengine.tools.development.BackendServersFilter.doFilter(BackendServersFfilter.java:97)网址：org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)网址：org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388)网址：org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)网址：org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)网址：org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)网址：org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418)网址：com.google.apphosting.utils.jetty.DevAppEngineWebAppContext.handle(DevAppEngineWebApp Context.java:70)网址：org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)网址：com.google.aappengine.tools.development.JettyContainerService$ApiProxyHandler.handle(JettyContainerServices.java:351)网址：org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)网址：org.mortbay.jetty.Server.handle(Server.java:326)网址：org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)网址：org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:923)网址：org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:547)网址：org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)网址：org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)网址：org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409)位于org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedTthreadPool.java:582)引起原因：java.lang.ClassNotFoundException：org.apache.jsp.guestbook_jsp位于java.net.URLClassLoader$1.run(URLClassLoader.java:202)位于java.security.AccessController.doPrivileged(本机方法)位于java.net.URLClassLoader.findClass(URLClassLoader.java:190)网址：org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:134)网址：org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:66)网址：org.apache.jasper.JspCompilationContext.load(JspCompillationContext.java:628)…还有38原因：
java.lang.ClassNotFoundException：org.apache.jsp.guestbook_jsp位于java.net.URLClassLoader$1.run(URLClassLoader.java:202)位于java.security.AccessController.doPrivileged(本机方法)位于java.net.URLClassLoader.findClass(URLClassLoader.java:190)网址：org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:134)网址：org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:66)网址：org.apache.jasper.JspCompilationContext.load(JspCompillationContext.java:628)网址：org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletsWrapper.java:144)网址：org.apache.jasper.servlet.JspServletWrapper.service(JspServletsWrapper.java:329)网址：org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)网址：org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)网址：com.google.aappengine.tools.development.PrivilegedJspServlet.access$101(PrivilegedJspServlet.java:23)网址：com.google.aappengine.tools.development.PrivilegedJspServlet$2.run(PrivilegedJspServlet.java:59)位于java.security.AccessController.doPrivileged(本机方法)网址：com.google.aappengine.tools.development.PrivilegedJspServlet.service(PrivilegedJspServlet.java:57)位于javax.servlet.httpHttpServlet.service(HttpServlet.java：717)网址：org.mortbay.japty.servlet.ServletHolder.handle(ServletHolder.java:511)网址：org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(servlet处理程序.java：1166)网址：com.google.aappengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:35)网址：org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)网址：com.google.aappengine.api.blobstore.dev.ServiceBlobFilter.doFilter(ServeBlobFilter.java:58)网址：org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)网址：com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43)网址：org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)网址：com.google.aappengine.tools.development.StaticFileFilter.doFilter(StaticFileFilter.java:122)网址：org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)网址：com.google.aappengine.tools.development.BackendServersFilter.doFilter(BackendServersFfilter.java:97)网址：org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)网址：org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388)网址：org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)网址：org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)网址：org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)网址：org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418)网址：com.google.apphosting.utils.jetty.DevAppEngineWebAppContext.handle(DevAppEngineWebApp Context.java:70)网址：org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)网址：com.google.aappengine.tools.development.JettyContainerService$ApiProxyHandler.handle(JettyContainerServices.java:351)网址：org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)网址：org.mortbay.jetty.Server.handle(Server.java:326)网址：org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)网址：org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:923)网址：org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:547)网址：org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)网址：org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)网址：org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409)位于org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedTthreadPool.java:582)
为了运行JSP页面，您需要JDK，我想您的项目没有关联的JDK。尝试将jdk库添加到您的项目环境中。我希望这能解决的问题