Time for action – the first run
Let's now perform the initial execution of this algorithm on our starting representation of the graph:
- Put the previously created
graph.txt
file onto HDFS:$ hadoop fs -mkdirgraphin $ hadoop fs -put graph.txtgraphin/graph.txt
- Compile the job and create the JAR file:
$ javac GraphPath.java $ jar -cvf graph.jar *.class
- Execute the MapReduce job:
$ hadoop jar graph.jarGraphPathgraphingraphout1
- Examine the output file:
$ hadoop fs –cat /home/user/hadoop/graphout1/part-r00000 12,3,40D 21,41C 31,5,61C 41,21C 53,6-1P 63,5-1P 76-1P
What just happened?
After putting the source file onto HDFS and creating the job JAR file, we executed the job in Hadoop. The output representation of the graph shows a few changes, as follows: ...
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