java代码操作hadoop基本命令（基本版）_import org.apache.hadoop.conf.configuration;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.BlockLocation;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.LocatedFileStatus;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.RemoteIterator;
import org.apache.hadoop.io.IOUtils;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URI;
import java.net.URISyntaxException;

public class hdfs {
   

    private final String hdfs_path="hdfs://bigdata01:9000";
    private FileSystem fileSystem=null;
    private Configuration configuration=null;

    @Before
    public void setUp() throws URISyntaxException, IOException, InterruptedException {
   

        //获取Configuration配置对象
        configuration = new Configuration();
        //设置副本数
        //configuration.set("dfs.replication","2");
        //初始化文件系统连接，此时需要在windows中配置环境变量HADOOP_USER_NAME了
        fileSystem = FileSystem.get(new URI(hdfs_path),configuration,"AzF");
        System.out.println("----------------------已经连接上集群-------------------------");
        System.out.println("\n");
    }



    //打印配置文件信息
    @Test
    public void test() throws IOException{
   
        System.out.println(configuration);
        System.out.println(fileSystem);
    }

    //创建目录
    @Test
    public void mkdirs() throws IOException {
   
        fileSystem.mkdirs(new Path("/input/aa/bb/cc"));
        //可以同时创建多级目录 /aaa/bbb/ccc
        System.out.println("成功创建HDFS 文件目录");
    }

    //创建文
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