从Blobstore读取Excel文件时出错

Question

我正在使用gwt 2.4。我可以从txt文件读取，但无法从Excel文件读取。 我也可以加载图像，但我看不到问题。
我下面的代码：

FileService fileService = FileServiceFactory.getFileService(); 
BlobKey blobKey = new BlobKey("NGIaxo54x--DEHtPBy5bLw"); 
AppEngineFile appFile = fileService.getBlobFile(blobKey); 

FileReadChannel readChannel = fileService.openReadChannel(appFile, false); 
BufferedReader reader = new BufferedReader(Channels.newReader(readChannel, "UTF8")); 
String line = reader.readLine(); 
System.out.println("Data : "+line); 

，我发现了以下错误：

java.nio.charset.MalformedInputException: Input length = 1 
at java.nio.charset.CoderResult.throwException(Unknown Source) 
at sun.nio.cs.StreamDecoder.implRead(Unknown Source) 
at sun.nio.cs.StreamDecoder.read(Unknown Source) 
at java.io.BufferedReader.fill(Unknown Source) 
at java.io.BufferedReader.readLine(Unknown Source) 
at java.io.BufferedReader.readLine(Unknown Source) 
at com.wa.gwtamazon.server.BlobServiceImpl.getPicture(BlobServiceImpl.java:75) 
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) 
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) 
at java.lang.reflect.Method.invoke(Unknown Source) 
at com.google.appengine.tools.development.agent.runtime.Runtime.invoke(Runtime.java:104) 
at com.google.gwt.user.server.rpc.RPC.invokeAndEncodeResponse(RPC.java:569) 
at com.google.gwt.user.server.rpc.RemoteServiceServlet.processCall(RemoteServiceServlet.java:208) 
at com.google.gwt.user.server.rpc.RemoteServiceServlet.processPost(RemoteServiceServlet.java:248) 
at com.google.gwt.user.server.rpc.AbstractRemoteServiceServlet.doPost(AbstractRemoteServiceServlet.java:62) 
at javax.servlet.http.HttpServlet.service(HttpServlet.java:637) 
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) 
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511) 
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166) 
at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:35) 
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:60) 
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43) 
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
at com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFileFilter.java:122) 
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
at com.google.appengine.tools.development.BackendServersFilter.doFilter(BackendServersFilter.java:97) 
at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388) 
at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216) 
at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182) 
at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765) 
at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418) 
at com.google.appengine.tools.development.DevAppEngineWebAppContext.handle(DevAppEngineWebAppContext.java:78) 
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) 
at com.google.appengine.tools.development.JettyContainerService$ApiProxyHandler.handle(JettyContainerService.java:362) 
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) 
at org.mortbay.jetty.Server.handle(Server.java:326) 
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542) 
at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:938) 
at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:755) 
at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218) 
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404) 
at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409) 
at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582) 

我还发现，这是一个错误，但还是没有找到任何解决方案。

Answer 1

当字符编码有问题时，MalformedInputException被抛出。

检查该文件是否实际上在UTF-8,下检查您的IDE，最后但并非最不重要的代码。

希望这有助于:)