Learn java.util.zip package
java.util.zip package tutorial

java.util.zip package provides classes for reading and writing the standard ZIP and GZIP file formats. Also includes classes for compressing and decompressing data using the DEFLATE compression algorithm, which is used by the ZIP and GZIP file formats. Additionally, there are utility classes for computing the CRC-32 and Adler-32 checksums of arbitrary input streams.

This reference will take you through simple and practical methods available in java.util.zip package.

This reference has been prepared for the beginners to help them understand the basic functionality related to all the methods available in java.util.zip package.

Before you start doing practice with various types of examples given in this reference, I'm making an assumption that you are already aware of basic Java Programming.