存儲(chǔ)越困難耳璧，提取越容易

HDFS客戶端操作---開(kāi)發(fā)環(huán)境準(zhǔn)備

步驟一：編譯對(duì)應(yīng)HadoopJar包内舟，配置Hadoop變量

image-20200622092736684

步驟二：創(chuàng)建Maven工程，導(dǎo)入pom依賴

<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>2.7.2</version>
        </dependency>
        <dependency>
            <groupId>org.apache.hadoop</groupId>
            <artifactId>hadoop-client</artifactId>
            <version>2.7.2</version>
        </dependency>
        <dependency>
            <groupId>org.apache.hadoop</groupId>
            <artifactId>hadoop-hdfs</artifactId>
            <version>2.7.2</version>
        </dependency>
</dependencies>

步驟三：創(chuàng)建日志文件

在resources目錄下創(chuàng)建log4j.properties，輸入如下信息

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

步驟四：創(chuàng)建HDFSClient類

public class HDFSClient{    

@Test
public void testMkdirs() throws IOException, InterruptedException, URISyntaxException{
        
        // 1 獲取文件系統(tǒng)
        Configuration configuration = new Configuration();

        // 2 連接集群
        FileSystem fs = FileSystem.get(new URI("hdfs://hadoop102:9000"), configuration, "zhutiansama");
        
        // 3 創(chuàng)建目錄
        fs.mkdirs(new Path("/1108/daxian/banzhang"));
        
        // 4 關(guān)閉資源
        fs.close();
    }
}

? 客戶端去操作HDFS時(shí)护桦，是有一個(gè)用戶身份的巧号。默認(rèn)情況下族奢，HDFS客戶端API會(huì)從JVM中獲取一個(gè)參數(shù)來(lái)作為自己的用戶身份：-DHADOOP_USER_NAME=zhutiansama，zhutiansama為用戶名稱丹鸿。至此Hadoop的Win開(kāi)發(fā)環(huán)境搭建完成越走，大家可以通過(guò)API去操作Hadoop啦

相關(guān)資料

1

本文配套GitHub：https://github.com/zhutiansama/FocusBigData