请问求用户相似度Jaccard参考代码中的,parts是输入样本数据中的每行数据吗?还是表示电影ID?parts[0]和parts[1]分别表示什么呢?有大神可以解释下下面代码分别是执行什么操作吗?
public class Mapper21 extends Mapper<Object, Text, IntWritable, Text> {
public void map(Object key, Text line, Context context) throws IOException, InterruptedException {
String[] parts = line.toString().split("\t");
if (parts.length < 2) {
return;
}
String[] userIds = parts[0].split(",");
if (userIds.length < 2) {
return;
}
context.write(new IntWritable(Integer.parseInt(userIds[0])), new Text(userIds[1] + ","
+ parts[1]));
}
}