Goto any specific folder and download the project using git clone.

git clone https://github.com/rangareddy/hdfs-java-api.git

mvn clean package

java -jar target/hdfs-java-api-1.0-SNAPSHOT.jar hdfs://localhost:8020

2020-03-31 15:29:55 INFO  HDFSClient:59 - Configuration object built successfully with the params {fs.defaultFS=hdfs://localhost:8020} \
2020-03-31 15:29:55 WARN  NativeCodeLoader:60 - Unable to load native-hadoop library for your platform... using builtin-java classes where applicable \
2020-03-31 15:29:56 INFO  HDFSJavaAPIDemo:33 - Creating a hdfs dir /ranga/hdfs/data/ \
2020-03-31 15:29:56 INFO  HDFSClient:53 - HDFS directory  created successfully. \
2020-03-31 15:29:56 INFO  HDFSJavaAPIDemo:36 - Creating a file /ranga/hdfs/data/README.md in hdfs. \
2020-03-31 15:29:57 INFO  HDFSClient:36 - HDFS directory  deleted successfully. \
2020-03-31 15:29:59 INFO  HDFSFileWriter:78 - Data is successfully written to hdfsPath  \
2020-03-31 15:29:59 INFO  HDFSJavaAPIDemo:45 - File  created successfully \
2020-03-31 15:29:59 INFO  HDFSJavaAPIDemo:47 - Reading data from hdfs file  \
2020-03-31 15:30:00 INFO  HDFSJavaAPIDemo:49 - File content \
2020-03-31 15:30:00 INFO  HDFSJavaAPIDemo:51 - Renaming a file \
2020-03-31 15:30:00 INFO  HDFSClient:67 - HDFS File /ranga/hdfs/data/README.md is successfully renamed to /ranga/hdfs/data/README_1.md \
2020-03-31 15:30:00 INFO  HDFSJavaAPIDemo:54 - Listing file(s) under  directory. \
2020-03-31 15:30:00 INFO  HDFSJavaAPIDemo:58 - hdfs://localhost:8020/ranga/hdfs/data/README_1.md \
2020-03-31 15:30:00 INFO  HDFSJavaAPIDemo:61 - Deleting a hdfs dir  \
2020-03-31 15:30:01 INFO  HDFSClient:36 - HDFS directory  deleted successfully. \

If u want to use this code in production remove the following two lines from ConfigUtils.java file

System.setProperty("hadoop.home.dir", "/");
System.setProperty("HADOOP_USER_NAME", "hdfs");