File count in an HDFS directory

user_1125953 0
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In Java code, I want to connect to a directory in HDFS, learn the number of files in that directory, get their names and want to read them. I can already read the files but I couldn't figure out how to count files in a directory and get file names like an ordinary directory.

In order to read I use DFSClient and open files into InputStream.

hdfs hadoop java
6 Answers

count

Usage: hadoop fs -count [-q] <paths>

Count the number of directories, files and bytes under the paths that match the specified file pattern. The output columns are: DIR_COUNT, FILE_COUNT, CONTENT_SIZE FILE_NAME.

The output columns with -q are: QUOTA, REMAINING_QUATA, SPACE_QUOTA, REMAINING_SPACE_QUOTA, DIR_COUNT, FILE_COUNT, CONTENT_SIZE, FILE_NAME.

Example:

hadoop fs -count hdfs://nn1.example.com/file1 hdfs://nn2.example.com/file2
hadoop fs -count -q hdfs://nn1.example.com/file1

Exit Code:

Returns 0 on success and -1 on error.

You can just use the FileSystem and iterate over the files inside the path. Here is some example code

int count = 0;
FileSystem fs = FileSystem.get(getConf());
boolean recursive = false;
RemoteIterator<LocatedFileStatus> ri = fs.listFiles(new Path("hdfs://my/path"), recursive);
while (ri.hasNext()){
    count++;
    ri.next();
}
user_24864950 
FileSystem fs = FileSystem.get(conf);
Path pt = new Path("/path");
ContentSummary cs = fs.getContentSummary(pt);
long fileCount = cs.getFileCount();
user_11259530

You can use the following to check file count in that particular directory

hadoop fs -count /directoryPath/* | print $2 | wc -l

count : counts the number of files, directories, and bytes under the path

print $2 : To print second column from the output

wc -l : To check the line count

user_135133910

hadoop fs -du [-s] [-h] [-x] URI [URI ...]

Displays sizes of files and directories contained in the given directory or the length of a file in case its just a file.

Options:

The -s option will result in an aggregate summary of file lengths being displayed, rather than the individual files. Without the -s option, calculation is done by going 1-level deep from the given path.
The -h option will format file sizes in a “human-readable” fashion (e.g 64.0m instead of 67108864)
The -x option will exclude snapshots from the result calculation. Without the -x option (default), the result is always calculated from all INodes, including all snapshots under the given path.
user_100589120
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