簡單的hdfs上傳,下載實現
1.使用idea導入hdfs的基本包
方法一:複製粘貼法導jar包 項目工程下新建lib文件夾------>複製hadoop的jar包到文件夾下:
hadoop-2.7.3/share/hadoop/common下的包(包含lib下的包)
hadoop-2.7.3/share/hadoop/hdfs(包含lib下的包)
------>選中lib目錄下所有jar包,右鍵------>Add as library
方法二:**maven**搭建hadoop環境新建maven項目------>直接在pom.xml文件裏添加hadoop的依賴包hadoop-common, hadoop-client, hadoop-hdfs即可
例如:
- <project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://maven.apache.org/POM/4.0.0"
- xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
- <modelVersion>4.0.0</modelVersion>
- <groupId>my.hadoopstudy</groupId>
- <artifactId>hadoopstudy</artifactId>
- <packaging>jar</packaging>
- <version>1.0-SNAPSHOT</version>
- <name>hadoopstudy</name>
- <url>http://maven.apache.org</url>
- <dependencies>
- <dependency>
- <groupId>org.apache.hadoop</groupId>
- <artifactId>hadoop-common</artifactId>
- <version>2.7.3</version>
- </dependency>
- <dependency>
- <groupId>org.apache.hadoop</groupId>
- <artifactId>hadoop-hdfs</artifactId>
- <version>2.7.3</version>
- </dependency>
- <dependency>
- <groupId>org.apache.hadoop</groupId>
- <artifactId>hadoop-client</artifactId>
- <version>2.7.3</version>
- </dependency>
- <dependency>
- <groupId>junit</groupId>
- <artifactId>junit</artifactId>
- <version>3.8.1</version>
- <scope>test</scope>
- </dependency>
- </dependencies>
- </project>
public class hadoop1 { public static FileSystem fs; public void init() throws Exception{ // 創建FileSystem類 fs = FileSystem.get(new URI("hdfs://192.168.19.128:9000"),new Configuration()); } @Test public void downLoad() throws Exception { init(); // 從hdfs下載文件到本地目錄 fs.copyToLocalFile(new Path("/wordcount"),new Path("D:/hadoop_test/1")); } @Test public void upLoad() throws Exception { init(); //上傳本地文件到hdfs上 fs.copyFromLocalFile(new Path("D:/hadoop_test/1"),new Path("/2")); } @Test public void deletedfs() throws Exception { init(); //刪除hdfs文件 fs.delete(new Path("/2"),false); } }
注意:可以通過50070端口查看hdfs界面
例如: http://192.168.19.128:50070/