Hadoop reuse reducer value input (buffer style)

Reducer.java

public void reduce(LongWritable key, Iterable<LongWritable> values,
				Context context) throws IOException, InterruptedException {

			List<LongWritable> buffer = new ArrayList<LongWritable>();
			List<LongWritable> buffer2 = new ArrayList<LongWritable>();
			for (LongWritable val : values) {
				buffer.add(new LongWritable(val.get()));
				buffer2.add(new LongWritable(val.get()));
			}