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HDFS >> mail # user >> Context Object in Map Reduce


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Context Object in Map Reduce
Hi everyone,
I am trying to pass a string variable from Driver class to Mapper class.
I came to know that i need to use context variable for this purpose.
But the Mapper method i have used has a signature without context object.
It is not allowing to change the method signature.(reporting syntax error)
Can anyone please suggest me what can I do regarding this?
I am very new to Map Reduce Programming.

Here is the code:

class Map<V> extends MapReduceBase implements Mapper<LongWritable, Text,
Text, IntWritable>
{
    String myfilename;
  private Text word = new Text();
  private IntWritable var = new IntWritable();

  public void map(LongWritable key, Text value, *Context
context,*OutputCollector<Text, IntWritable> output, Reporter reporter)
*//here is the error *
 throws IOException
{
         Configuration conf = context.getConfiguration();
             myfilename = conf.get("filename");
             -- - - -- - -- -
        }
 public  void compute() throws Exception
  {
  Configuration config = new Configuration();
      config.set("filename", "Syn-100n-8t-2l-2k.vars");

    JobConf conf = new JobConf(Hadoop_GNTS.class);
    -- - - - -- - -
}

Thanks
+
manish dunani 2013-07-26, 14:33
+
manish dunani 2013-07-26, 14:56
+
Tanniru Govardhan 2013-07-26, 15:36
NEW: Monitor These Apps!
elasticsearch, apache solr, apache hbase, hadoop, redis, casssandra, amazon cloudwatch, mysql, memcached, apache kafka, apache zookeeper, apache storm, ubuntu, centOS, red hat, debian, puppet labs, java, senseiDB