zoukankan      html  css  js  c++  java
  • Hadoop 写SequenceFile文件 源代码

    package com.tdxx.hadoop.sequencefile;
    
    import java.io.IOException;
    
    import org.apache.hadoop.conf.Configuration;
    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.SequenceFile;
    import org.apache.hadoop.io.SequenceFile.Writer;
    
    public class SequenceFileStudy{
    
    	/**
    	 * 写入到sequence file
    	 * 
    	 * @param filePath
    	 * @param conf
    	 * @param datas
    	 */
    	public static void write2SequenceFile(String filePath, Configuration conf,
    			LongWritable key,LongWritable val) {
    		FileSystem fs = null;
    		Writer writer = null;
    		Path path = null;
    		//LongWritable idKey = new LongWritable(0);
    
    		try {
    			fs = FileSystem.get(conf);
    			path = new Path(filePath);
    			writer = SequenceFile.createWriter(fs, conf, path,
    					LongWritable.class, LongWritable.class);
    			writer.append(key, val);
    			
    		} catch (IOException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		} finally {
    			IOUtils.closeStream(writer);
    		}
    	}
    
    	private static Configuration getDefaultConf() {
    		Configuration conf = new Configuration();
    		conf.set("mapred.job.tracker", "local");
    		conf.set("fs.default.name", "file:///");
    		return conf;
    	}
    
    	/**
    	 * @param args
    	 */
    	public static void main(String[] args) {
    		String filePath = "data/longValue.sequence"; // 文件路径
    		
    		// 生成数据
    		for (int i = 1; i <= 20; i++) {
    			// 写入到sequence file
    			LongWritable key = new LongWritable(i);
    			LongWritable value = new LongWritable(i+1);
    			write2SequenceFile(filePath, getDefaultConf(), key,value);
    		}
    	}
    
    }


  • 相关阅读:
    【mybatis】IF判断的坑
    QCheckBox控件
    对话框——文件对话框
    对话框——颜色对话框
    对话框——输入对话框
    事件和信号
    布局管理——复习示例
    布局管理——网格布局
    布局管理——盒式布局
    1.4 控制流
  • 原文地址:https://www.cnblogs.com/snake-hand/p/3170326.html
Copyright © 2011-2022 走看看