Hadoop 客户端环境准备

前提：安装windows Hadoop

一、IDEA

IntelliJ IDEA

二、搭建

1、创建maven项目

2、导入依赖

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>
            <version>2.8.2</version>
        </dependency>
        <dependency>
            <groupId>org.apache.hadoop</groupId>
            <artifactId>hadoop-common</artifactId>
            <version>2.7.7</version>
        </dependency>
        <dependency>
            <groupId>org.apache.hadoop</groupId>
            <artifactId>hadoop-client</artifactId>
            <version>2.7.7</version>
        </dependency>
        <dependency>
            <groupId>org.apache.hadoop</groupId>
            <artifactId>hadoop-hdfs</artifactId>
            <version>2.7.7</version>
        </dependency>
    </dependencies>

3、src/main/resource

创建 log4j.properties

log4j.rootLogger=INFO, stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d %p [%c] - %m%n
log4j.appender.logfile=org.apache.log4j.FileAppender
log4j.appender.logfile.File=target/spring.log
log4j.appender.logfile.layout=org.apache.log4j.PatternLayout
log4j.appender.logfile.layout.ConversionPattern=%d %p [%c] - %m%n

 4、案例

package com.wt.hdfs;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;

public class HDFSClient {
    public static void main(String[] args) throws IOException, URISyntaxException, InterruptedException {
        // 1. 获取HDFS客户对象
        Configuration conf = new Configuration();
        FileSystem fs = FileSystem.get(new URI("hdfs://wt1:9000"), conf, "tom");
        // 2. 在HDFS上创建路径
        fs.mkdirs(new Path("/wt/li"));

        // 3.关闭资源
        fs.close();

        System.out.println("over");
    }
}