import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.log4j.Level;
import org.apache.log4j.Logger;

public class App {
  public static void main(String[] args) throws IOException {
    Logger.getRootLogger().setLevel(Level.OFF);

    Configuration config = new Configuration();
    config.set("fs.default.name", "hdfs://YOUR.IP.ADDRESS:9000/");

    Path inputFilePath = new Path("/helloDir/test_file.txt");
    FileSystem dfs = FileSystem.get(config);
    BufferedReader br = new BufferedReader(new InputStreamReader(dfs.open(inputFilePath)));
    String line;
    while ( (line = br.readLine()) != null) {
      System.out.println(line);
    }

    dfs.close();
  }
}
						

Use the following pom.xml to automatically download all of the requirements:

<?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>edu.umkc.sce.csee.dbis.hadoop</groupId>
  <artifactId>Hadoop</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>
  <name>Hadoop</name>
  <url>http://maven.apache.org</url>
  <properties>
   <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>
  <dependencies>
   <dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>3.8.1</version>
    <scope>test</scope>
   </dependency>
   <dependency>
    <groupId>org.apache.hadoop</groupId>
    <artifactId>hadoop-client</artifactId>
    <version>2.7.3</version>
   </dependency>
  </dependencies>
</project>