Question

我无法使用Java从HDFS读取文件：

String hdfsUrl = "hdfs://<ip>:<port>";
Configuration configuration = new Configuration();
configuration.set("fs.defaultFS", hdfsUrl);
FileSystem fs = FileSystem.get(configuration);
Path filePath = new Path(hdfsUrl + "/projects/harmonizome/data/achilles/attribute_list_entries.txt.gz");
FSDataInputStream fsDataInputStream = fs.open(filePath);

SEVERE: Servlet.service() for servlet [edu.mssm.pharm.maayanlab.Harmonizome.api.DownloadAPI] in context with path [/Harmonizome] threw exception
java.lang.IllegalArgumentException: Wrong FS: hdfs://146.203.54.165:8020/projects/harmonizome/data/achilles/attribute_list_entries.txt.gz, expected: file:///
    at org.apache.hadoop.fs.FileSystem.checkPath(FileSystem.java:310)
    at org.apache.hadoop.fs.RawLocalFileSystem.pathToFile(RawLocalFileSystem.java:47)
    at org.apache.hadoop.fs.RawLocalFileSystem.getFileStatus(RawLocalFileSystem.java:357)
    at org.apache.hadoop.fs.FilterFileSystem.getFileStatus(FilterFileSystem.java:245)
    at org.apache.hadoop.fs.ChecksumFileSystem$ChecksumFSInputChecker.<init>(ChecksumFileSystem.java:125)
    at org.apache.hadoop.fs.ChecksumFileSystem.open(ChecksumFileSystem.java:283)
    at org.apache.hadoop.fs.FileSystem.open(FileSystem.java:356)
    at edu.mssm.pharm.maayanlab.Harmonizome.api.DownloadAPI.readLines(DownloadAPI.java:37)
    at edu.mssm.pharm.maayanlab.Harmonizome.api.DownloadAPI.doGet(DownloadAPI.java:27)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
...

我没有设置我们的HDFS，所以我不知道我不知道什么。任何帮助表示赞赏。

Answer 1

试试这个：

Configuration configuration = new Configuration();
FileSystem fs = FileSystem.get(new URI(<url:port>), configuration);
Path filePath = new Path(<path/to/file>);
FSDataInputStream fsDataInputStream = fs.open(filePath);
BufferedReader br = new BufferedReader(new InputStreamReader(fsDataInputStream));

请参阅http://techidiocy.com/java-lang-illegalargumentexception-wrong-fs-expected-file/

解决了类似的问题。

Answer 2

以下配置也可以！

Configuration conf = new Configuration();
conf.addResource(new Path("/usr/hdp/2.6.3.0-235/hadoop/etc/hadoop/core-site.xml"));
FileSystem fs = FileSystem.get(conf);

＆＃34;错误的FS ...预期：file：///＆＃34;当试图从Java中读取HDFS中的文件时

2 个答案: