[root@master hadoop-3.1.1]# bin/hadoop jar share/hadoop/mapreduce/hadoop-mapreduce-examples-3.1.1.jar
An example program must be given as the first argument.
Valid program names are:
aggregatewordcount: An Aggregate based map/reduce program that counts the words in the input files.
aggregatewordhist: An Aggregate based map/reduce program that computes the histogram of the words in the input files.
bbp: A map/reduce program that uses Bailey-Borwein-Plouffe to compute exact digits of Pi.
dbcount: An example job that count the pageview counts from a database.
distbbp: A map/reduce program that uses a BBP-type formula to compute exact bits of Pi.
grep: A map/reduce program that counts the matches of a regex in the input.
join: A job that effects a join over sorted, equally partitioned datasets
multifilewc: A job that counts words from several files.
pentomino: A map/reduce tile laying program to find solutions to pentomino problems.
pi: A map/reduce program that estimates Pi using a quasi-Monte Carlo method.
randomtextwriter: A map/reduce program that writes 10GB of random textual data per node.
randomwriter: A map/reduce program that writes 10GB of random data per node.
secondarysort: An example defining a secondary sort to the reduce.
sort: A map/reduce program that sorts the data written by the random writer.
sudoku: A sudoku solver.
teragen: Generate data for the terasort
terasort: Run the terasort
teravalidate: Checking results of terasort
wordcount: A map/reduce program that counts the words in the input files.
wordmean: A map/reduce program that counts the average length of the words in the input files.
wordmedian: A map/reduce program that counts the median length of the words in the input files.
有效的程序名稱是：
aggregatewordcount：一個基於聚合的map/reduce程序，它對輸入文件中的單詞進行計數。
aggregatewordhist：一個基於聚合的map/reduce程序，用於計算輸入文件中單詞的直方圖。
bbp:一個使用Bailey Borwein Plouffe計算PI精確數字的map/reduce程序。
dbcount：一個計算頁面瀏覽量的示例作業，從數據庫中計數。
distbbp：一個使用BBP型公式計算PI精確比特的map/reduce程序。
grep:一個在輸入中計算正則表達式匹配的map/reduce程序。
join：一個影響連接排序、相等分區數據集的作業
multifilewc:一個從多個文件中計算單詞的任務。
pentomino:一個地圖/減少瓦片鋪設程序來找到解決PotoMimo問題的方法。
pi:一個用擬蒙特卡洛方法估計PI的MAP/Relp程序。
randomtextwriter：一個map/reduce程序，每個節點寫入10GB的隨機文本數據。
randomwriter：一個映射/RADIUS程序，每個節點寫入10GB的隨機數據。
secondarysort：定義一個次要排序到減少的例子。
sort：一個對隨機寫入器寫入的數據進行排序的map/reduce程序。
sudoku：數獨求解者。
teragen:為terasort生成數據
terasort：運行terasort
teravalidate: terasort的檢查結果
wordcount：一個映射/縮小程序，計算輸入文件中的單詞。
wordmean:map/reduce程序，用於計算輸入文件中單詞的平均長度。
wordmedian:map/reduce程序，用於計算輸入文件中單詞的中值長度。