谷歌应用引擎-java.io.EOFException GDrive API授权

Question

我目前正在关注https://developers.google.com/drive/v3/web/quickstart/java从doogle驱动器获取文件列表的教程。在我得到以下异常

Caused by:
java.io.EOFException
    at java.io.ObjectInputStream$PeekInputStream.readFully(Unknown Source)
    at java.io.ObjectInputStream$BlockDataInputStream.readShort(Unknown Source)
    at java.io.ObjectInputStream.readStreamHeader(Unknown Source)
    at java.io.ObjectInputStream.<init>(Unknown Source)
    at com.google.api.client.util.IOUtils.deserialize(IOUtils.java:171)
    at com.google.api.client.util.store.FileDataStoreFactory$FileDataStore.<init>(FileDataStoreFactory.java:102)
    at com.google.api.client.util.store.FileDataStoreFactory.createDataStore(FileDataStoreFactory.java:73)
    at com.google.api.client.util.store.AbstractDataStoreFactory.getDataStore(AbstractDataStoreFactory.java:55)
    at com.google.api.client.auth.oauth2.StoredCredential.getDefaultDataStore(StoredCredential.java:171)
    at com.google.api.client.auth.oauth2.AuthorizationCodeFlow$Builder.setDataStoreFactory(AuthorizationCodeFlow.java:736)
    at com.google.api.client.googleapis.auth.oauth2.GoogleAuthorizationCodeFlow$Builder.setDataStoreFactory(GoogleAuthorizationCodeFlow.java:209)
    at com.demo.gapps.server.FetchNewFilesCron.authorize(FetchNewFilesCron.java:233)
    at com.demo.gapps.server.FetchNewFilesCron.getDriveService(FetchNewFilesCron.java:244)
    at com.demo.gapps.server.FetchNewFilesCron.doGet(FetchNewFilesCron.java:97)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166)
    at com.google.appengine.api.socket.dev.DevSocketFilter.doFilter(DevSocketFilter.java:74)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.google.appengine.tools.development.ResponseRewriterFilter.doFilter(ResponseRewriterFilter.java:128)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:34)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:63)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:50)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFileFilter.java:125)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.google.appengine.tools.development.DevAppServerModulesFilter.doDirectRequest(DevAppServerModulesFilter.java:366)
    at com.google.appengine.tools.development.DevAppServerModulesFilter.doDirectModuleRequest(DevAppServerModulesFilter.java:349)
    at com.google.appengine.tools.development.DevAppServerModulesFilter.doFilter(DevAppServerModulesFilter.java:116)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388)
    at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
    at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
    at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)
    at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418)
    at com.google.appengine.tools.development.DevAppEngineWebAppContext.handle(DevAppEngineWebAppContext.java:98)
    at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
    at com.google.appengine.tools.development.JettyContainerService$ApiProxyHandler.handle(JettyContainerService.java:511)
    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$RequestHandler.headerComplete(HttpConnection.java:923)
    at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:547)
    at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)
    at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
    at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409)
    at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)

我使用教程中的代码来授权生成的潜在异常，如下所示：

* @return an authorized Credential object.
         * @throws IOException
         */
        public static Credential authorize() throws IOException {
            System.out.println("file path is "+DATA_STORE_DIR.getPath());
            // Load client secrets.
            InputStream in =
                FetchNewFilesCron.class.getResourceAsStream("/client_secrets.json");
            GoogleClientSecrets clientSecrets =
                GoogleClientSecrets.load(JSON_FACTORY, new InputStreamReader(in));

            // Build flow and trigger user authorization request.
            GoogleAuthorizationCodeFlow flow =
                    new GoogleAuthorizationCodeFlow.Builder(
                            HTTP_TRANSPORT, JSON_FACTORY, clientSecrets, SCOPES)
                    .setDataStoreFactory(DATA_STORE_FACTORY)
                    .setAccessType("offline")
                    .build();
            Credential credential = new AuthorizationCodeInstalledApp(
                flow, new LocalServerReceiver()).authorize("user");
            System.out.println(
                    "Credentials saved to " + DATA_STORE_DIR.getAbsolutePath());
            return credential;
        }

错误可能在.setDataStoreFactory(DATA_STORE_FACTORY)

有谁能帮我纠正这个错误吗。

谢谢，

Answer 1

异常表示意外到达end of file (EOF)或流的末尾。此外，此异常主要由DataInputStreams使用，以便用信号通知流的结束。但是，请注意，其他输入操作可能会在流结束时返回一个特殊值，而不是抛出EOFException。

EOFException类扩展了IOException类，IOException类是由失败或中断的I/O操作产生的异常的一般类。此外，它实现了Serializable接口。此外，它被定义为已检查异常，因此，它必须在方法或构造函数的throws子句中声明。

DataInputStreams提供了可以以独立于机器的方式从底层输入流读取原始Java数据类型的方法。应用程序通过使用OutputStream类或DataOutputStream类别提供的方法来写入数据。

有关更多信息，请查看此相关的SO票证，其中讨论了EOFException和DataInputStream：java.io.EOFException当尝试从套接字中读取时

Answer 2

我知道这是一篇旧帖子，但我有几乎完全相同的堆栈，唯一的答案没有太大帮助。所以，我发帖希望它能帮助那些在我之后的人。

该问题似乎与文件/目录权限有关。一旦我将FileDataStoreFactory使用的文件路径更改为应用程序具有读/写权限的目录，OAuth2就可以正常工作。因此，请确保您使用的是非受限文件路径，并且所有目录都具有正确的所有权和权限。