mapreduce.py 文件源码

def doMap(self, i):
        f = open("#split-%s-%s" % (self.path, i), "r")
        keyvalue = f.readline()
        value = f.read()
        f.close()
        os.unlink("#split-%s-%s" % (self.path, i))
        keyvaluelist = self.Map(keyvalue, value)
        for r in range(0, self.reducetask):
            # print "map", i, "#map-%s-%s-%d" % (self.path, i, r)
            f = open("#map-%s-%s-%d" % (self.path, i, r), "w+")
            itemlist = [item for item in keyvaluelist if self.Partition(item) == r]
            pickle.dump(itemlist, f)
            f.close()
        return [(i, r) for r in range(0, self.reducetask)]

    # Get reduce regions from maptasks, sort by key, and apply Reduce for each key