在网站会员中,会员积分不同。此程序是求Reputation最高的10个用户。用的测试文件为users.xml(见本系列第一节云盘地址)
代码如下
package mrdp.ch3;
import java.io.IOException;
import java.util.Map;
import java.util.TreeMap;
import mrdp.utils.MRDPUtils;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.Reducer;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.util.GenericOptionsParser;
public class TopTenDriver {
public static class SOTopTenMapper extends
Mapper<Object, Text, NullWritable, Text> {
// Our output key and value Writables
private TreeMap<Integer, Text> repToRecordMap = new TreeMap<Integer, Text>();
@Override
public void