【快速入门大数据】Hadoop集成Spring的使用

官网sprng-hadoop

​​https://spring.io/projects/spring-hadoop​​

添加依赖

<dependencies>
    <dependency>
        <groupId>org.springframework.data</groupId>
        <artifactId>spring-data-hadoop</artifactId>
        <version>2.5.0.RELEASE</version>
    </dependency>
</dependencies>

使用spring hadoop配置及查看HDFS文件

新建资源文件beans.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:hdp="http://www.springframework.org/schema/hadoop"
        xsi:schemaLocation="
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/hadoop
        http://www.springframework.org/schema/hadoop/spring-hadoop.xsd">

    <hdp:configuration id="hadoopConfiguration">
        fs.defaultFS=hdfs://hadoop01:9000
        hadoop.tmp.dir=/tmp/hadoop
        electric=sea
    </hdp:configuration>

    <hdp:file-system id="fileSystem"
                     configuration-ref="hadoopConfiguration"
                     user="root"
    />

</beans>

测试文件

package com.bennyrhys.hadoop.spring;

import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IOUtils;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import java.io.IOException;

/**
 * @Author bennyrhys
 * @Date 1/21/21 2:35 PM
 */
public class SpringHadoopHDFSApp {
    private ApplicationContext ctx;
    // apache hadoop
    private FileSystem fileSystem;

    /**
     * 创建HDFS文件夹
     */
    @Test
    public void testMkdirs() throws Exception {
        fileSystem.mkdirs(new Path("/springhdfs"));
    }

    /**
     * 查看HDFS文件
     */
    @Test
    public void testText() throws Exception {
        FSDataInputStream in = fileSystem.open(new Path("/springhdfs/hello.txt"));
        IOUtils.copyBytes(in, System.out, 1024);
        in.close();
    }

    @Before
    public void setUp() {
        ctx = new ClassPathXmlApplicationContext("beans.xml");
        fileSystem = (FileSystem) ctx.getBean("fileSystem");
    }

    @After
    public void tearDown() throws Exception {
        ctx = null;
        fileSystem.close();
    }
}

spring hadoop 配置文件详解

提取变量

使用xml中的头文件替换bean，使其允许使用上下文

${}导入变量

新建配置文件application.properties

spring.hadoop.fsUri=hdfs://hadoop01:9000

获取context上下文引入变量

beans.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:hdp="http://www.springframework.org/schema/hadoop"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/hadoop http://www.springframework.org/schema/hadoop/spring-hadoop.xsd">

    <hdp:configuration id="hadoopConfiguration">
        fs.defaultFS=${spring.hadoop.fsUri}
        hadoop.tmp.dir=/tmp/hadoop
        electric=sea
    </hdp:configuration>
    <context:property-placeholder location="application.properties"/>

    <hdp:file-system id="fileSystem"
                     configuration-ref="hadoopConfiguration"
                     user="root"
    />

</beans>

SpringBoot访问HDFS系统

pom.xml

<!-- 添加spring boot的依赖操作hadoop -->
    <dependency>
      <groupId>org.springframework.data</groupId>
      <artifactId>spring-data-hadoop-boot</artifactId>
      <version>2.5.0.RELEASE</version>
    </dependency>

SpringBootHDFSApp

package com.bennyrhys.hadoop.spring;

import org.apache.hadoop.fs.FileStatus;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.data.hadoop.fs.FsShell;

/**
 * @Author bennyrhys
 * @Date 1/21/21 11:33 PM
 */
@SpringBootApplication
public class SpringBootHDFSApp implements CommandLineRunner {

    @Autowired
    FsShell fsShell; //引入spring的

    @Override
    public void run(String... strings) throws Exception {
        for (FileStatus fileStatus : fsShell.lsr("/springhdfs")) {
            System.out.println("> " + fileStatus.getPath());
        }
    }

    /**
     * > hdfs://hadoop01:9000/springhdfs
     * > hdfs://hadoop01:9000/springhdfs/hello.txt
     * @param args
     */
    public static void main(String[] args) {
        SpringApplication.run(SpringBootHDFSApp.class, args);
    }
}