• HDFS之FileSystem


    package cn.hx.test;
    
    import org.apache.hadoop.conf.Configuration;
    import org.apache.hadoop.fs.*;
    import org.apache.hadoop.io.IOUtils;
    import org.apache.log4j.BasicConfigurator;
    
    import java.io.FileInputStream;
    import java.io.IOException;
    import java.net.URI;
    
    public class test1 {
        public static void main(String[] args) throws IOException {
            BasicConfigurator.configure();
            try {
                //链接hdfs的URL
                URI uri = new URI("hdfs://192.168.22.131:9000");
                Configuration conf = new Configuration();
                FileSystem fileSystem = FileSystem.get(uri, conf);
    
    
                //filestatus表示hdfs中的每一个文件夹
                FileStatus[] listStatus = fileSystem.listStatus(new Path("/"));
                for (FileStatus fileStatus : listStatus) {
    
                    System.out.println(fileStatus);
                    System.out.println("文件路径:" + fileStatus.getPath());
                    System.out.println("是否是一个目录:" + fileStatus.isDirectory());
                    System.out.println("修改时间:" + fileStatus.getModificationTime());
                    System.out.println("访问时间:" + fileStatus.getAccessTime());
                    System.out.println("所有者:" + fileStatus.getOwner());
                    System.out.println("用户:" + fileStatus.getGroup());
                    System.out.println("文件权限:" + fileStatus.getPermission());
                    System.out.println("是否是?:" + fileStatus.getSymlink());
    
                }
            } catch (Exception e) {
            }
        }
        //下载文件
        private static void open(FileSystem fileSystem) throws IOException {
            FSDataInputStream in = fileSystem.open(new Path("/test/1"));
            IOUtils.copyBytes(in, System.out, 1024, true);
        }
    
    
        //上传文件
        private static void put(FileSystem fileSystem) throws IOException {
            FSDataOutputStream out = fileSystem.create(new Path("/test/1"));
            FileInputStream in = new FileInputStream("u202AE:\BigDataVideos\Hadoop 7\2015-12-30 【hadoop】\edits.xml");
            IOUtils.copyBytes(in, out, 1024, true);
        }
    
    
    }

    结果:

  • 相关阅读:
    R语言 which() 、 which.min() 、 which.max() 函数
    R rep() 函数
    R语言 一个向量的值分派给另一个向量
    R语言 sample抽样函数
    超参数 hyperparameters
    随机游走模型(Random Walk)
    随机数
    Lambda 函数与表达式
    static
    变量的申明定义
  • 原文地址:https://www.cnblogs.com/huxinga/p/6883315.html
Copyright © 2020-2023  润新知