day02_小笔记---HDFS的API操作

忘是亡心i 2023-07-02 09:28 47阅读 0赞

# **HDFS的API操作：** #

**1.首先在idea里创建一个Maven工程HdfsClientDemo**

**2.导入相应的依赖坐标+日志添加（pom.xml）**

<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>
    		<dependency>
    			<groupId>jdk.tools</groupId>
    			<artifactId>jdk.tools</artifactId>
    			<version>1.8</version>
    			<scope>system</scope>
    			<systemPath>${JAVA_HOME}/lib/tools.jar</systemPath>
    		</dependency>
    </dependencies>

**3.需要在项目的src/main/resources目录下，新建一个文件，命名为“log4j.properties”，在文件中填入**

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.创建包名：com.atguigu.hdfs**

**5.创建HdfsClient类以及上传文件的代码**

package com.zpark.hdfs;
    
    import org.apache.hadoop.conf.Configuration;
    import org.apache.hadoop.fs.FileSystem;
    import org.apache.hadoop.fs.Path;
    import org.junit.Test;
    
    
    import java.io.File;
    import java.io.IOException;
    import java.net.URI;
    
    public class HdfsClient {
    
    
        @Test
        public void put()throws IOException,InterruptedException{
    
            
            FileSystem fileSystem =FileSystem.get(URI.create("hdfs://hdp-1:9000"),new Configuration(),"root");
    
            fileSystem.copyFromLocalFile(new Path("d:\\1.txt"),new Path("/"));
    
            fileSystem.close();
        }
    }

**6.在启动hdfs**

[root@hdp-1 ~]# start-dfs.sh
    Starting namenodes on [hdp-1]
    hdp-1: starting namenode, logging to /root/apps/hadoop-2.8.1/logs/hadoop-root-namenode-hdp-1.out
    hdp-4: starting datanode, logging to /root/apps/hadoop-2.8.1/logs/hadoop-root-datanode-hdp-4.out
    hdp-2: starting datanode, logging to /root/apps/hadoop-2.8.1/logs/hadoop-root-datanode-hdp-2.out
    hdp-3: starting datanode, logging to /root/apps/hadoop-2.8.1/logs/hadoop-root-datanode-hdp-3.out
    hdp-1: starting datanode, logging to /root/apps/hadoop-2.8.1/logs/hadoop-root-datanode-hdp-1.out
    Starting secondary namenodes [hdp-2]
    hdp-2: starting secondarynamenode, logging to /root/apps/hadoop-2.8.1/logs/hadoop-root-secondarynamenode-hdp-2.out

**7.在d盘创建1.txt，在运行idea**

8.在登录[http://hdp-1:50070/][http_hdp-1_50070]

查看是否有1.txt

[http_hdp-1_50070]: http://hdp-1:50070/