write-file

write-file

A simple program that illustrates a few different ways to write to a file using the Java standard libraries.

Instructions

Follow these instructions to build and run the program:

1. Use Java 17
2. Build and run the program:
   • ./gradlew run --args append
   • This mode will append lines to a file.
3. Try a different write mode:
   • ./gradlew run --args truncate
   • This mode will truncate a file before writing to it.
4. Create a large file:
   • ./gradlew run --args large
   • This mode will generate a large file to tmp/large-file.txt.
5. Copy a file and make some substitution
   • ./gradlew run --args substitutions
   • This mode will copy the README.md file to a temp file and make some string substitutions.
6. Compress data and write it to a file:
   • ./gradlew run --args compress_gzip
   • Peek at the file contents with the following command.
   • gzip -cd tmp/file.txt.gz | head
7. Use a different compression algorithm:
   • ./gradlew run --args compress_zlib
   • Peek at the file contents with the following command.
   • perl -MCompress::Zlib -e 'undef $/; print uncompress(<>)' < tmp/file.txt.zz | head

Wish list

General clean ups, TODOs and things I wish to implement for this project:

• DONE Use compression (like gzip)
• DONE Use another compression type. Does anything offer parallelization?

Reference

• JavaDoc: java.util.zip.Deflater
• JNI binding for Zstd