hadoop下用于测试的KMeans程序

import java.io.ByteArrayOutputStream; import java.io.IOException; import java.net.URI; import java.util.StringTokenizer; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.FSDataInputStream; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.IOUtils; import org.apache.hadoop.io.LongWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapreduce.Mapper; public class KMapper extends Mapper<LongWritable, Text, Text, Text> { private String[] center; protected void setup(Context context) throws IOException,InterruptedException //read centerlist, and save to center[] { String centerlist = "hdfs://hust.site:9000/user/root/center/center"; //center文件 Configuration conf1 = new Configuration(); conf1.set("hadoop.job.ugi", "hadoop-user,hadoop-user"); FileSystem fs = FileSystem.get(URI.create(centerlist),conf1); FSDataInputStream in = null; ByteArrayOutputStream out = new ByteArrayOutputStream(); try{ in = fs.open( new Path(centerlist) ); IOUtils.copyBytes(in,out,100,false); center = out.toString().split(" "); }finally{ IOUtils.closeStream(in); } } public void map(LongWritable key,Text value,Context context) throws IOException,InterruptedException { StringTokenizer itr = new StringTokenizer(value.toString()); while(itr.hasMoreTokens()) { String outValue = new String(itr.nextToken()); String[] list = outValue.replace("(", "").replace(")", "").split(","); String[] c = center[0].replace("(", "").replace(")", "").split(","); float min = 0; int pos = 0; for(int i=0;i<list.length;i++) { min += (float) Math.pow((Float.parseFloat(list[i]) - Float.parseFloat(c[i])),2); } for(int i=0;i<center.length;i++) { String[] centerStrings = center[i].replace("(", "").replace(")", "").split(","); float distance = 0; for(int j=0;j<list.length;j++) distance += (float) Math.pow((Float.parseFloat(list[j]) - Float.parseFloat(centerStrings[j])),2); if(min>distance) { min=distance; pos=i; } } context.write(new Text(center[pos]), new Text(outValue)); } } }