这是我的代码：
Configuration conf = new Configuration();
conf.addResource(new Path("/etc/hadoop/conf/core-site.xml"));
conf.addResource(new Path("/etc/hadoop/conf/hdfs-site.xml"));
conf.addResource(new Path("/etc/hadoop/conf/mapred-site.xml"));
conf.addResource(new Path("/etc/hadoop/conf/yarn-site.xml"));
FileSystem fs = FileSystem.get(new URI("hdfs://localhost:8020"),conf);
Path path = new Path(hdfsDestination);
FSDataOutputStream outputStream = fs.create(path);
hdfsDestination是/ user / msknapp / insurance，这是输出：
java.io.IOException: Failed on local exception: com.google.protobuf.InvalidProtocolBufferException: Protocol message contained an invalid tag (zero).; Host Details : local host is: "localhost.localdomain/127.0.0.1"; destination host is: "localhost":8020;
at org.apache.hadoop.net.NetUtils.wrapException(NetUtils.java:764)
at org.apache.hadoop.ipc.Client.call(Client.java:1351)
at org.apache.hadoop.ipc.Client.call(Client.java:1300)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:206)
at com.sun.proxy.$Proxy9.create(Unknown Source)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:186)
at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:102)
at com.sun.proxy.$Proxy9.create(Unknown Source)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolTranslatorPB.create(ClientNamenodeProtocolTranslatorPB.java:227)
at org.apache.hadoop.hdfs.DFSOutputStream.newStreamForCreate(DFSOutputStream.java:1389)
at org.apache.hadoop.hdfs.DFSClient.create(DFSClient.java:1382)
at org.apache.hadoop.hdfs.DFSClient.create(DFSClient.java:1307)
at org.apache.hadoop.hdfs.DistributedFileSystem$6.doCall(DistributedFileSystem.java:384)
at org.apache.hadoop.hdfs.DistributedFileSystem$6.doCall(DistributedFileSystem.java:380)
at org.apache.hadoop.fs.FileSystemLinkResolver.resolve(FileSystemLinkResolver.java:81)
at org.apache.hadoop.hdfs.DistributedFileSystem.create(DistributedFileSystem.java:380)
at org.apache.hadoop.hdfs.DistributedFileSystem.create(DistributedFileSystem.java:324)
at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:905)
at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:886)
at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:783)
at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:772)
at knapp.hdfs.importer.insurance.InsuranceIO.writeToHdfsAsAvro(InsuranceIO.java:68)
at knapp.hdfs.importer.insurance.InsuranceIO.writeFileToHdfsAsAvro(InsuranceIO.java:51)
at knapp.hdfs.importer.ImporterCommandLine.run(ImporterCommandLine.java:72)
at knapp.hdfs.importer.ImporterCommandLine.main(ImporterCommandLine.java:61)
Caused by: com.google.protobuf.InvalidProtocolBufferException: Protocol message contained an invalid tag (zero).
at com.google.protobuf.InvalidProtocolBufferException.invalidTag(InvalidProtocolBufferException.java:89)
at com.google.protobuf.CodedInputStream.readTag(CodedInputStream.java:108)
at org.apache.hadoop.ipc.protobuf.RpcHeaderProtos$RpcResponseHeaderProto.<init>(RpcHeaderProtos.java:1398)
at org.apache.hadoop.ipc.protobuf.RpcHeaderProtos$RpcResponseHeaderProto.<init>(RpcHeaderProtos.java:1362)
at org.apache.hadoop.ipc.protobuf.RpcHeaderProtos$RpcResponseHeaderProto$1.parsePartialFrom(RpcHeaderProtos.java:1492)
at org.apache.hadoop.ipc.protobuf.RpcHeaderProtos$RpcResponseHeaderProto$1.parsePartialFrom(RpcHeaderProtos.java:1487)
at com.google.protobuf.AbstractParser.parsePartialFrom(AbstractParser.java:200)
at com.google.protobuf.AbstractParser.parsePartialDelimitedFrom(AbstractParser.java:241)
at com.google.protobuf.AbstractParser.parseDelimitedFrom(AbstractParser.java:253)
at com.google.protobuf.AbstractParser.parseDelimitedFrom(AbstractParser.java:259)
at com.google.protobuf.AbstractParser.parseDelimitedFrom(AbstractParser.java:49)
at org.apache.hadoop.ipc.protobuf.RpcHeaderProtos$RpcResponseHeaderProto.parseDelimitedFrom(RpcHeaderProtos.java:2364)
at org.apache.hadoop.ipc.Client$Connection.receiveRpcResponse(Client.java:996)
at org.apache.hadoop.ipc.Client$Connection.run(Client.java:891)
我让CDH4.8以伪分布式模式运行：
[msknapp@localhost conf]$ hadoop fs -ls /user/msknapp
Found 2 items
drwxr-xr-x - msknapp supergroup 0 2014-01-01 10:22 /user/msknapp/input
drwxr-xr-x - msknapp supergroup 0 2014-01-01 10:35 /user/msknapp/output23
[msknapp@localhost conf]$ hadoop fs -ls /user
Found 1 items
drwxrwxrwx - msknapp supergroup 0 2014-01-01 10:35 /user/msknapp
[msknapp@localhost conf]$ whereis hadoop
hadoop: /usr/bin/hadoop /etc/hadoop /usr/lib/hadoop /usr/share/man/man1/hadoop.1.gz
如果重要的话，我正在使用CentOS 6.4。我可以很好地从命令行将数据放入HDFS，但出于某种原因不能从代码中放入HDFS。有人可以告诉我为什么我不能用我的代码写入HDFS吗？
答案 0 :(得分：2)
我得到了相同的异常，我发现缺少一些依赖项，我只有hadoop-core但需要更多。当我添加它们时，它起作用了：
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-core</artifactId>
<version>2.0.0-mr1-cdh4.3.0</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-hdfs</artifactId>
<version>2.0.0-cdh4.3.0</version>
</dependency>
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-common</artifactId>
<version>2.0.0-cdh4.3.0</version>
</dependency>
答案 1 :(得分：0)
你想写这条路径“/ usr / msknapp / insurance”但是显示权限这条路径“/ user / msknapp”！
答案 2 :(得分：0)
似乎使用的是protobuf-java-X.jar的不兼容版本。请检查protobuf jar版本以构建您的应用程序以及CDH4.8中使用的内容