Question

I am trying to import a Hadoop class to use in my project.

import org.apache.hadoop.fs.*;

I would normally expect to go out into the world and try to find a Hadoop JAR file to include, put it in a libs folder in eclipse, then use the classes. Having done that and not found what I expected, I ask: what is the right way to include Hadoop classes in my own Java class so that I can use them in eclipse?

I found Hadoop documentation frustrating because it has an incredibly short shelf life. Advice from six months ago apparently is totally worthless.

Answer 1

Using maven and the m2e plugin, a hadoop project is as simple as:

<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>csw.hadoop</groupId>
    <artifactId>hadoop-sandbox</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <dependencies>
      <dependency>
        <groupId>org.apache.hadoop</groupId>
        <artifactId>hadoop-core</artifactId>
        <version>1.1.1</version>
        <scope>provided</scope>
      </dependency>
    </dependencies>
</project>

And maven will handle downloading the jar and dependencies for you, the Eclipse maven plugin will manage the build path for you.

I’m sure there’s a Eclipse ivy plugin too, that will do the same thing for Ant