This project extracts from the original commoncrawl project only the ARCInputFormat class and its dependencies. It also implement a new ARCSource, HDFSSource, which allows ARC files to be read from HDFS.

Differences from the original project:

• JetS3tARCSource is removed since it is not advisable to read directly from S3. It's more efficient to copy (using distcp) the arc files from S3 to HDFS and then read from HDFS.
• HDFSSource is the default ARCSource implementation.
• HDFSSource can accept both directory and individual files as input files. Directories will be recursively scanned for regular files.
• HDFSSource will check for input files using the P_INPUT variable (see HDFSExample). If it is null or empty it will check for input file given using the common [setInputPaths()](http://hadoop.apache.org/common/docs/current/api/org/apache/hadoop/mapred/FileInputFormat.html#setInputPaths(org.apache.hadoop.mapred.JobConf, java.lang.String))

How to compile

In order to ensure a successful compilation of the library please modify the build.proprieties file and set the hadoop.path variable correctly. Then simply invoke:

ant

You'll find ARCInputFormat.jar ready for use.