1.修改环境变量 ~/bash_profile
export ANDROID_HOME=~/Library/Android/sdk # added by Anaconda3 5.1.0 installer export PATH="/Users/walle/anaconda3/bin:$PATH" # hadoop export HADOOP_HOME=/usr/local/Cellar/hadoop/3.1.0/libexec export PATH=$PATH:$HADOOP_HOME/bin:$HADOOP_HOME/sbin for f in $HADOOP_HOME/share/hadoop/common/hadoop-*.jar;do export CLASSPATH=$CLASSPATH:$f done for f in $HADOOP_HOME/share/hadoop/hdfs/hadoop-*.jar;do export CLASSPATH=$CLASSPATH:$f done for f in $HADOOP_HOME/share/hadoop/mapreduce/hadoop-*.jar;do export CLASSPATH=$CLASSPATH:$f done for f in $HADOOP_HOME/share/hadoop/yarn/hadoop-*.jar;do export CLASSPATH=$CLASSPATH:$f done export CLASSPATH=$CLASSPATH:$HADOOP_HOME/share/common/lib:$HADOOP_HOME/share/hdfs/lib:$HADOOP_HOME/share/mapreduce/lib:$HADOOP_HOME/share/tools/lib:$HADOOP_HOME/share/yarn/lib
2.编译java 为jar文件
javac *.java jar -cvf MaxTemperature.jar .
在src目录执行上面2行代码，得到MaxTemperature.jar
3. 拷贝文件到hfs
#创建几个目录 hadoop fs -mkdir /user/ hadoop fs -mkdir /user/walle #拷贝文件 hadoop fs -put ./input/1901 /user/walle hadoop fs -put ./input/1902 /user/walle
4.执行mapreduce
hadoop jar ./src/MaxTemperature.jar MaxTemperature /user/walle /user/walle/output
5.查看结果
hadoop fs -cat /user/walle/output/part-r-00000
