renzeGIS 2018-06-28
文章说明:因Linux平台再GUI页面通过IDE进行Hadoop开发,会导致Linux在GUI上极度消耗资源,对于一些配置不是很高的PC,可能会出现卡顿的情况,非常影响程序编写,本文就详细介绍如何在windows平台进行hadoop开发,希望对各位学习Hadoop的同学优异
工具准备:
hadoop eclipse插件:hadoop-eclipse-plugin-2.7.3.jar
hadoop windows平台支持组件:winutils.exe
hadoop底层依赖库:hadoop.dll
上述工具下载地址:下载地址
Hadoop版本 : hadoop-2.7.3
开发步骤:
1. 启动hadoop : start-yarn.sh、start-dfs.sh (配置hadoop看历史文章)
2. windows本地配置Linux的主机IP映射:(不配置直接使用IP也行)
3. 将hadoop-eclipse-plugin-2.7.3.jar放进eclipse的plugins目录,启动eclipse
4. eclipse配置Hadoop
5. 切换MapReduce视图可以看到HDFS文件系统的信息
运行MapReduce程序配置步骤:
1. 配置HADOOP环境变量:主要将bin、sbin放入PATH路径
2. 将winutils.exe放在bin目录,hadoop.dll放在windows System32目录
3. 测试代码
import java.io.IOException; import java.util.StringTokenizer; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.IntWritable; import org.apache.hadoop.io.LongWritable; 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; /** * 统计文本词频信息 * @author Zerone1993 */ public class WordCount { static class WordMapper extends Mapper<LongWritable, Text, Text, IntWritable>{ @Override protected void map(LongWritable key, Text value, Mapper<LongWritable, Text, Text, IntWritable>.Context context) throws IOException, InterruptedException { String str = value.toString(); StringTokenizer st = new StringTokenizer(str); while(st.hasMoreTokens()){ String temp = st.nextToken(); context.write(new Text(temp), new IntWritable(1)); } } } static class WordReducer extends Reducer<Text, IntWritable, Text, IntWritable>{ @Override protected void reduce(Text arg0, Iterable<IntWritable> arg1, Reducer<Text, IntWritable, Text, IntWritable>.Context arg2) throws IOException, InterruptedException { int sum = 0; for(IntWritable temp : arg1){ sum = sum + temp.get(); } arg2.write(new Text(arg0), new IntWritable(sum)); } } public static void main(String[] args) { Configuration conf = new Configuration(); conf.set("mapred.job.tracker", "master:50020"); try{ Job job = Job.getInstance(conf, "wordCount"); job.setJarByClass(WordCount.class); //设置启动作业类 job.setMapperClass(WordMapper.class); //设置Map类 job.setReducerClass(WordReducer.class); job.setMapOutputKeyClass(Text.class); //设置mapper输出的key类型 job.setMapOutputValueClass(IntWritable.class); //设置mapper输出的value类型 job.setNumReduceTasks(1); //设置Reduce Task的数量 //设置mapreduce的输入和输出目录 FileInputFormat.addInputPath(job, new Path("hdfs://master:9090/user/squirrel/input/mapreduce/")); FileOutputFormat.setOutputPath(job, new Path("hdfs://master:9090/user/squirrel/output/mapreduce/") ); //等待mapreduce整个过程完成 System.exit(job.waitForCompletion(true)?0:1); }catch(Exception e){ e.printStackTrace(); } } } 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85
效果:
至此整个WINDOWS HADOOP环境搭建完毕