1.新建springboot项目

• 项目结构

  
  2020-11-28_231526.jpg

• pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>cn.itbin</groupId>
    <artifactId>hadoop03</artifactId>
    <version>1.0-SNAPSHOT</version>

    <!--引入父工程-->
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.0.RELEASE</version>
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.apache.hadoop</groupId>
            <artifactId>hadoop-client</artifactId>
            <version>3.2.1</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
    </dependencies>
</project>

• 将linux node01上的hdfs-site.xml和core-site.xml复制到resource目录下
  hdfs.xml

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<!--
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License. See accompanying LICENSE file.
-->

<!-- Put site-specific property overrides in this file. -->

<configuration>
<property>
        <name>dfs.replication</name>
        <value>2</value>
</property>
<property>
  <name>dfs.nameservices</name>
  <value>mycluster</value>
</property>
<property>
  <name>dfs.ha.namenodes.mycluster</name>
  <value>nn1,nn2,nn3</value>
</property>
#rpc通讯
<property>
  <name>dfs.namenode.rpc-address.mycluster.nn1</name>
  <value>node01:8020</value>
</property>
<property>
  <name>dfs.namenode.rpc-address.mycluster.nn2</name>
  <value>node02:8020</value>
</property>
<property>
  <name>dfs.namenode.rpc-address.mycluster.nn3</name>
  <value>node03:8020</value>
</property>
#http通讯
<property>
  <name>dfs.namenode.http-address.mycluster.nn1</name>
  <value>node01:9870</value>
</property>
<property>
  <name>dfs.namenode.http-address.mycluster.nn2</name>
  <value>node02:9870</value>
</property>
<property>
  <name>dfs.namenode.http-address.mycluster.nn3</name>
  <value>node03:9870</value>
</property>
<property>
  <name>dfs.namenode.shared.edits.dir</name>
  <value>qjournal://node01:8485;node02:8485;node03:8485/mycluster</value>
</property>
<property>
  <name>dfs.client.failover.proxy.provider.mycluster</name>
  <value>org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider</value>
</property>
<property>
  <name>dfs.ha.fencing.methods</name>
  <value>sshfence</value>
</property>

<property>
   <name>dfs.ha.fencing.ssh.private-key-files</name>
   <value>/root/.ssh/id_rsa</value>
</property>
<property>
  <name>dfs.journalnode.edits.dir</name>
  <value>/opt/hadoop/full/data</value>
</property>
<property>
   <name>dfs.ha.automatic-failover.enabled</name>
   <value>true</value>
</property>
<property>
        <name>dfs.permissions</name>
        <value>false</value>
</property>
</configuration>

core-site.xml

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<!--
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License. See accompanying LICENSE file.
-->

<!-- Put site-specific property overrides in this file. -->

<configuration>
<property>
      <name>fs.defaultFS</name>
      <value>hdfs://mycluster</value>
</property>
<property>
      <name>hadoop.tmp.dir</name>
      <value>/opt/hadoop/ha</value>
</property>
<property>
    <name>ha.zookeeper.quorum</name>
    <value>node02:2181,node03:2181,node04:2181</value>
</property>
</configuration>

• 编写测试

import cn.itbin.Application;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;

/**
 * @author chenxiaogao
 * @className TestDemo
 * @description TODO
 * @date 2020/11/28
 **/
@RunWith(SpringRunner.class)
@SpringBootTest(classes = Application.class)
public class TestDemo {

    private static final Logger logger = LoggerFactory.getLogger(TestDemo.class);

    Configuration conf;
    FileSystem fileSystem;

    @Before
    public void testConn() throws URISyntaxException, IOException, InterruptedException {
        conf = new Configuration(true);
        fileSystem = FileSystem.get(new URI("hdfs://node01:8020"),conf,"root");
    }

    @Test
    public void mkdir() throws IOException {
        //创建文件夹
        Path path = new Path("/myTemp01");
        boolean exists = fileSystem.exists(path);
        if (exists) {
            fileSystem.delete(path, true);
        }
        if (fileSystem.mkdirs(path)) {
            logger.info("{}已创建",path.getName());
//创建成功后可登陆node01:9870查看该目录
        }

    }

    @After
    public void testClose() {
        try {
            fileSystem.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

}