Win10 IDEA连接虚拟机中的Hadoop（HDFS）

ip a

sudo ufw disable

# 位置可能不一样，和Hadoop安装位置有关
cd /usr/local/hadoop/etc/hadoop
vim core-site.xml

cd /usr/local/hadoop/ #目录可能不一样，修改成自己的目录
./sbin/stop-dfs.sh # 关闭hadoop
./sbin/start-dfs.sh #启动hadoop
jps # 判断是否启动成功

  <properties>
    <hadoop.version>3.3.5</hadoop.version>
  </properties>
  <dependencies>
    <dependency>
      <groupId>org.apache.hadoop</groupId>
      <artifactId>hadoop-common</artifactId>
      <version>${hadoop.version}</version>
    </dependency>

    <dependency>
      <groupId>org.apache.hadoop</groupId>
      <artifactId>hadoop-hdfs</artifactId>
      <version>${hadoop.version}</version>
    </dependency>

    <dependency>
      <groupId>org.apache.hadoop</groupId>
      <artifactId>hadoop-client</artifactId>
      <version>${hadoop.version}</version>
    </dependency>
  </dependencies>

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.*;

import java.io.IOException;

public class Test01 {
    public static void main(String[] args) throws IOException {
        Configuration conf = new Configuration();
        //  设置用户名（一定要，不然默认用户名是win的用户名）
        System.setProperty("HADOOP_USER_NAME","hadoop");
        // 	IP地址修改成虚拟机的ip
        conf.set("fs.defaultFS","hdfs://192.168.111.131:9000");
        conf.set("fs.hdfs.impl","org.apache.hadoop.hdfs.DistributedFileSystem");
        FileSystem fs = FileSystem.get(conf);

        RemoteIterator<LocatedFileStatus> files = fs.listFiles(new Path("/"), true);
        while (files.hasNext()) {
            FileStatus fileStatus = files.next();
            System.out.println(fileStatus.getPath().toString());
        }
        fs.close(); //关闭hdfs
    }
}

@REM 设置IP
SET BigDataLANIP=192.168.111.131 


@REM 设置命令以管理员身份运行
%1 start "" mshta vbscript:CreateObject("Shell.Application").ShellExecute("cmd.exe","/c %~s0 ::","","runas",1)(window.close)&&exit
@REM  清空所有转发规则
netsh interface portproxy reset


@REM 转发9000
netsh interface portproxy add v4tov4 listenport=9000 connectport=9000 connectaddress=%BigDataLANIP%
@REM 转发9870（HDFS的web管理界面）
netsh interface portproxy add v4tov4 listenport=9870 connectport=9870 connectaddress=%BigDataLANIP%
echo "succeed"
timeout /t 5 /nobreak >nul

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.*;


import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;


public class Test02 {
    public static void main(String[] args) throws IOException {
        Configuration conf = new Configuration();
//        设置用户名（一定要，不然默认用户名是win的用户名）
        System.setProperty("HADOOP_USER_NAME","hadoop");
        conf.set("fs.defaultFS","hdfs://localhost:9000");
        conf.set("fs.hdfs.impl","org.apache.hadoop.hdfs.DistributedFileSystem");
//        列出根目录下的所有文件和文件夹
        FileSystem fs = FileSystem.get(conf);
        Path file = new Path("/");
        FileStatus[] fileStatuses = fs.listStatus(file);
        for (FileStatus fileStatus : fileStatuses){
            System.out.println(fileStatus.getPath());
        }
//        创建一个新的文件 test.txt 在HDFS的 /user/hadoop/test 目录下（如果目录不存在，则先创建目录）。
        Path dirPath = new Path("/user/hadoop/test");
        if(!fs.exists(dirPath)){
            fs.mkdirs(dirPath);
        }
        Path remotePath = new Path("/user/hadoop/test/test.txt");
        FSDataOutputStream outputStream = fs.create(remotePath);
        outputStream.close();
//        向 test.txt 文件中写入一段指定的文本内容（如“Hello, HDFS!”）。
        FSDataOutputStream outputStream2 = fs.create(remotePath);
        String s = "Hello, HDFS!";
        outputStream2.write(s.getBytes());
        outputStream2.close();
//       读取 test.txt 文件的内容，并打印到控制台。
        FSDataInputStream inputStream = fs.open(remotePath);
        BufferedReader d = new BufferedReader(new InputStreamReader(inputStream));
        String line = null;
        while ((line = d.readLine()) != null)
            System.out.println(line);
//      关闭与HDFS的连接。
        fs.close();
    }
}