Hi All, I'm new to Giraph and related hadoop projects. After playing with it for several days I finally get the shortest path example running. The roadblock turns out to be the file input format setting in GiraphRunner.java.
With the input files provided at wiki page, the shortest path example should work out of the box. However, the following command will lead to a IOException in master thread, $ hadoop jar giraph-0.2-SNAPSHOT-for-hadoop-1.0.2-jar-with-dependencies.jar org.apache.giraph.GiraphRunner org.apache.giraph.examples.SimpleShortestPathsVertex -w 3 -if org.apache.giraph.io.formats.JsonLongDoubleFloatDoubleVertexInputFormat -ip shortestPathsInputGraph -of org.apache.giraph.io.formats.JsonLongDoubleFloatDoubleVertexOutputFormat -op shortestPathsOutputGraph The reason is that the underlying TextVertexInputFormat reads data from GiraphTextInputFormat but GiraphRunner sets input path with hadoop.mapreduce.lib.input.FileInputFormat. To run the shortest path example, the GiraphRunner.java should import org.apache.giraph.io.formats.GiraphFileInputFormat and should use GiraphFileInputFormat.addVertexInputPath to set the path. However, I'm not sure whether this modification will make GiraphRunner less general. Regards, Jiadong
